free will does not exist essay

Why the Classical Argument Against Free Will Is a Failure

In the last several years, a number of prominent scientists have claimed that we have good scientific reason to believe that there’s no such thing as free will — that free will is an illusion. If this were true, it would be less than splendid. And it would be surprising, too, because it really seems like we have free will. It seems that what we do from moment to moment is determined by conscious decisions that we freely make.

We need to look very closely at the arguments that these scientists are putting forward to determine whether they really give us good reason to abandon our belief in free will. But before we do that, it would behoove us to have a look at a much older argument against free will — an argument that’s been around for centuries.

The older argument against free will is based on the assumption that determinism is true. Determinism is the view that every physical event is completely caused by prior events together with the laws of nature. Or, to put the point differently, it’s the view that every event has a cause that makes it happen in the one and only way that it could have happened.

If determinism is true, then as soon as the Big Bang took place 13 billion years ago, the entire history of the universe was already settled. Every event that’s ever occurred was already predetermined before it occurred. And this includes human decisions. If determinism is true, then everything you’ve ever done — every choice you’ve ever made — was already predetermined before our solar system even existed. And if this is true, then it has obvious implications for free will.

Suppose that you’re in an ice cream parlor, waiting in line, trying to decide whether to order chocolate or vanilla ice cream. And suppose that when you get to the front of the line, you decide to order chocolate. Was this choice a product of your free will? Well, if determinism is true, then your choice was completely caused by prior events. The immediate causes of the decision were neural events that occurred in your brain just prior to your choice. But, of course, if determinism is true, then those neural events that caused your decision had physical causes as well; they were caused by even earlier events — events that occurred just before they did. And so on, stretching back into the past. We can follow this back to when you were a baby, to the very first events of your life. In fact, we can keep going back before that, because if determinism is true, then those first events were also caused by prior events. We can keep going back to events that occurred before you were even conceived, to events involving your mother and father and a bottle of Chianti.

If determinism is true, then as soon as the Big Bang took place 13 billion years ago, the entire history of the universe was already settled.

So if determinism is true, then it was already settled before you were born that you were going to order chocolate ice cream when you got to the front of the line. And, of course, the same can be said about all of our decisions, and it seems to follow from this that human beings do not have free will.

Let’s call this the classical argument against free will . It proceeds by assuming that determinism is true and arguing from there that we don’t have free will.

There’s a big problem with the classical argument against free will. It just assumes that determinism is true. The idea behind the argument seems to be that determinism is just a commonsense truism. But it’s actually not a commonsense truism. One of the main lessons of 20th-century physics is that we can’t know by common sense, or by intuition, that determinism is true. Determinism is a controversial hypothesis about the workings of the physical world. We could only know that it’s true by doing some high-level physics. Moreover — and this is another lesson of 20th-century physics — as of right now, we don’t have any good evidence for determinism. In other words, our best physical theories don’t answer the question of whether determinism is true.

During the reign of classical physics (or Newtonian physics), it was widely believed that determinism was true. But in the late 19th and early 20th centuries, physicists started to discover some problems with Newton’s theory, and it was eventually replaced with a new theory — quantum mechanics . (Actually, it was replaced by two new theories, namely, quantum mechanics and relativity theory. But relativity theory isn’t relevant to the topic of free will.) Quantum mechanics has several strange and interesting features, but the one that’s relevant to free will is that this new theory contains laws that are probabilistic rather than deterministic. We can understand what this means very easily. Roughly speaking, deterministic laws of nature look like this:

If you have a physical system in state S, and if you perform experiment E on that system, then you will get outcome O.

But quantum physics contains probabilistic laws that look like this:

If you have a physical system in state S, and if you perform experiment E on that system, then there are two different possible outcomes, namely, O1 and O2; moreover, there’s a 50 percent chance that you’ll get outcome O1 and a 50 percent chance that you’ll get outcome O2.

It’s important to notice what follows from this. Suppose that we take a physical system, put it into state S, and perform experiment E on it. Now suppose that when we perform this experiment, we get outcome O1. Finally, suppose we ask the following question: “Why did we get outcome O1 instead of O2?” The important point to notice is that quantum mechanics doesn’t answer this question . It doesn’t give us any explanation at all for why we got outcome O1 instead of O2. In other words, as far as quantum mechanics is concerned, it could be that nothing caused us to get result O1 ; it could be that this just happened .

Now, Einstein famously thought that this couldn’t be the whole story. You’ve probably heard that he once said that “God doesn’t play dice with the universe.” What he meant when he said this was that the fundamental laws of nature can’t be probabilistic. The fundamental laws, Einstein thought, have to tell us what will happen next, not what will probably happen, or what might happen. So Einstein thought that there had to be a hidden layer of reality , below the quantum level, and that if we could find this hidden layer, we could get rid of the probabilistic laws of quantum mechanics and replace them with deterministic laws, laws that tell us what will happen next, not just what will probably happen next. And, of course, if we could do this — if we could find this hidden layer of reality and these deterministic laws of nature — then we would be able to explain why we got outcome O1 instead of O2.

But a lot of other physicists — most notably, Werner Heisenberg and Niels Bohr — disagreed with Einstein. They thought that the quantum layer of reality was the bottom layer. And they thought that the fundamental laws of nature — or at any rate, some of these laws — were probabilistic laws. But if this is right, then it means that at least some physical events aren’t deterministically caused by prior events. It means that some physical events just happen . For instance, if Heisenberg and Bohr are right, then nothing caused us to get outcome O1 instead of O2; there was no reason why this happened; it just did .

The debate between determinists like Einstein and indeterminists like Heisenberg and Bohr has never been settled.

The debate between Einstein on the one hand and Heisenberg and Bohr on the other is crucially important to our discussion. Einstein is a determinist. If he’s right, then every physical event is predetermined — or in other words, completely caused by prior events. But if Heisenberg and Bohr are right, then determinism is false . On their view, not every event is predetermined by the past and the laws of nature; some things just happen , for no reason at all. In other words, if Heisenberg and Bohr are right, then indeterminism is true.

And here’s the really important point for us. The debate between determinists like Einstein and indeterminists like Heisenberg and Bohr has never been settled. We don’t have any good evidence for either view. Quantum mechanics is still our best theory of the subatomic world, but we just don’t know whether there’s another layer of reality, beneath the quantum layer. And so we don’t know whether all physical events are completely caused by prior events. In other words, we don’t know whether determinism or indeterminism is true. Future physicists might be able to settle this question, but as of right now, we don’t know the answer.

But now notice that if we don’t know whether determinism is true or false, then this completely undermines the classical argument against free will. That argument just assumed that determinism is true. But we now know that there is no good reason to believe this. The question of whether determinism is true is an open question for physicists. So the classical argument against free will is a failure — it doesn’t give us any good reason to conclude that we don’t have free will.

Despite the failure of the classical argument, the enemies of free will are undeterred. They still think there’s a powerful argument to be made against free will. In fact, they think there are two such arguments. Both of these arguments can be thought of as attempts to fix the classical argument, but they do this in completely different ways.

The first new-and-improved argument against free will — which is a scientific argument — starts with the observation that it doesn’t matter whether the full-blown hypothesis of determinism is true because it doesn’t matter whether all events are predetermined by prior events. All that matters is whether our decisions are predetermined by prior events. And the central claim of the first new-and-improved argument against free will is that we have good evidence (from studies performed by psychologists and neuroscientists) for thinking that, in fact, our decisions are predetermined by prior events.

The second new-and-improved argument against free will — which is a philosophical argument, not a scientific argument — relies on the claim that it doesn’t matter whether determinism is true because in determinism is just as incompatible with free will as determinism is. The argument for this is based on the claim that if our decisions aren’t determined, then they aren’t caused by anything, which means that they occur randomly . And the central claim of the second new-and-improved argument against free will is that if our decisions occur randomly, then they just happen to us , and so they’re not the products of our free will.

My own view is that neither of these new-and-improved arguments succeeds in showing that we don’t have free will. But it takes a lot of work to undermine these two arguments. In order to undermine the scientific argument, we need to explain why the relevant psychological and neuroscientific studies don’t in fact show that we don’t have free will. And in order to undermine the philosophical argument, we need to explain how a decision could be the product of someone’s free will — how the outcome of the decision could be under the given person’s control — even if the decision wasn’t caused by anything.

So, yes, this would all take a lot of work. Maybe I should write a book about it.

Mark Balaguer is Professor in the Department of Philosophy at California State University, Los Angeles. He is the author of several books, including “ Free Will ,” from which this article is adapted.

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Why free will doesn't exist, according to Robert Sapolsky

It's hard to let go of the idea that free will exists, but neuroscientist Robert Sapolsky says that society starts to look very different once you do

By Timothy Revell

18 October 2023

Robert Sapolsky is one of the most revered scientists alive today. He made his name from his work studying wild baboons in Kenya, unpicking how their complex social lives lead to stress and how that affects their health.

His most recent focus, however, has been on something rather different – a book that comprehensively argues that free will doesn’t exist in any shape or form.

As he writes: “We are nothing more or less than the sum of that which we could not control – our biology, our environments, their interactions”.

In this episode of CultureLab, Sapolsky outlines his case against free will and what a society without free will should look like.

You can find New Scientist Podcasts on your favourite podcast platform or by clicking here .

Determined: A Science of Life Without Free Will is out now.

Timothy Revell: Many of our listeners, they will know you as someone who spent years studying wild baboons, and then, also, as an eminent neuroscientist, so what made you decide to then suddenly look at free will so closely, which is, I guess, more often associated with philosophy? Was there, like, an enticing incident? Did something get you onto it first?

Robert Sapolsky: Yes. I turned fourteen years old, at one point, and had a somewhat existentially unnerving experience and, that night, woke up at around two in the morning and say, “Aha, I get it. There’s no God, there’s no purpose, and there’s no free will,” and it’s been, kind of, like that every since.

More approximately, about five years ago, I published a book called, Behave, The Biology of Humans at our Best and Wors t, and I did a lot of public lecturing about, sort of, the general subject in the years since. And you’d go through, sort of, an hour’s talk of telling people about, the events one second before behaviour and one minute, and one hour, and one thousand years and all these different influences. With some regularity, somebody in the audience, afterwards, with Q&A, would say something like, “Wow. All this stuff, kind of, makes one wonder about free will,” which I, in effect, would say, “You think?” and it just struck me that I needed to write something that, very expectantly, tackled how completely silly and bankrupt the notion of free will is, when you put all the relevant science together.

Then dealing with the bigger issue, I know it seems very straightforward and simplistic by now to me that there’s no free will, but the massive issue of, “Ph my God, what are we supposed to do if people actually started believing this? How are we supposed to function?’

Timothy Revell: It’s funny that you say it’s now so easy to say that free will doesn’t exist, but I think for many people it’s one of those things that, subjectively, it feels very real, but then, you know, a good argument against that is a tale feels solid, but it’s mostly empty space, so we can’t really trust what we think about the world, certainly not our own experience of it. For those that haven’t spent as much time thinking about free will and reached the conclusion that you have, that it doesn’t exist, what is the argument? What does science say about free will?

Robert Sapolsky: Well, my essential song and dance, and I should add about 90-95 per cent of philosophers agree, that there’s free will, and steadfastly hold onto it, and these are folks, who classify themselves as compatibilists, which is to say they’re willing to admit there are things like atoms and molecules and cells out there, but somehow, despite that, can still pull free will out of the hat in their thinking.

In terms of my orientation, my basic approach is you look at a behaviour and someone has just done something that’s wonderful or awful or ambiguously in-between or in the eyes of the beholder, but some behaviour has happened, and you ask, “Why did that occur?” and you’re asking a whole hierarchy of questions. You’re, of course, asking, “Which neurons did what, ten milliseconds before?” but you’re also asking, “What sensory stimuli in the previous minutes triggered that?” but you’re also asking, “What did this morning’s hormone levels have to do with how sensitive your brain would be to those stimuli?”

You’re also asking, “What have the previous months been, trauma, stimulation, whatever, in terms of neuroplasticity?” and before you know it, you’re back to adolescents and your last gasp of constructing your frontal cortex, and childhood and foetal environment and it’s epigenetic consequences, and of course, genes. Amazingly, at that point, you have to push further back. What sort of culture were your ancestors inventing and what sort of ecosystems prompted those inventions, because that was influencing how your mother was mothering you within minutes of birth, and then, you know, some evolution thrown in for good measure.

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What you see at that point is, not just saying, “Wow, when you look at all these different disciplines, collectively, they’re showing we’re just biological machines,” but they’re not all these different disciplines. They’re all one continuous one. If you’re talking about genes, by definition, genes and behaviour, by definition, you’re talking about evolution and you’re talking about neurobiology and genetic variance and neuronal function. If you’re talking about, you know, early trauma in life, you’re talking about epigenetics and you’re talking about adult propensity. So, they’re all one continuous seam of influences, and when you look at it that way, there’s not a damn crack anywhere in there to shoehorn in a notion of free will.

Timothy Revell: You talk about this in your book, but I think, for many people, they still feel like maybe there’s room. You know, with each individual step, it feels like those are influences rather than the 100 per cent determining factor. Is there, when people come to you and say, “Oh, but there’s still a little bit of room,” you know, “These are all things that influence me on a given day. of course, if it’s hot, I’m more likely to go outside and enjoy the sun, but it’s still my decision,” how do you go from that, from influences, to, “It’s not just influences, everything we do is dictated in one way or another, by this whole combination of factors’?

Robert Sapolsky: Well, the jerky, sort of, challenge that I lay down at that point is, “Okay, so you’re still holding out for free will somewhere in there, just because it seems so counter-intuitive if that is all we are,” but look at some behaviour, you just pulled the trigger on a gun, like something very consequential, and you could probably even identify the three-and-a-half neurons in the motor cortex that sent that command to your muscles.

Show me, let’s examine those three-and-a-half neurons that just did that. Show me that what they did was completely impervious to what was going on in any other neuron surrounding them, but at the same time, show me that it was impervious to whether you were tired, stressed, sleepy, happy, well-fed, at that moment. Show me that it’s impervious and would’ve done the exact same thing no matter what your hormone levels were this morning, no matter what your childhood was, no matter what your genome is, the epigenetics. Show me that it would’ve done the exact same thing after changing any of those or all of those variables, and as far as I’m concerned, you’ve just proven free will, and they can’t, because there’s absolutely nothing any of your, like, molecules making you up just did to generate a behaviour that’s independent of every second before.

It is impossible to show that we can act freely of everything that came before.

Timothy Revell: Do you think there’s a reason why we seem so wired to think that free will does exist? Is there some evolutionary benefit to us believing that? If we just accepted it from the beginning, that it doesn’t exist, would that maybe actually be better for us, overall?

Robert Sapolsky: Oh, well, at first pass, it’s depressing as hell and alarming and unsettling and all of that, and all sorts of wise evolutionary biologists have thought about the evolution of self-deception, and by the time you’re as smart of a primate as we are, we had to have developed a robust capacity for not believing in what might be the case, because otherwise, it would be all too overwhelming and despairing and just existential void and all that stuff.

You know, there’s a very, very strong emotional incentive to feel agency, and endless aspects of experimental psychology has shown that you stress people or frazzle them or give them an unsolvable problem, and they get a way distorted sense of agency, at that point, as a defence. The really critical issue there though is the assumption that believing there’s no free will, okay, there’s no free will and you better believe it, and that’s about as appealing as, like, swallowing cod liver oil or something but, you know, suck it up, that’s the way the world works.

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My overwhelmingly emphasis is, if you suddenly are convinced there’s no free will, and that’s a total bummer for you, because that makes your, like, egregiously privileged salary seem like something you did not necessarily earn and your prestigious degrees and your circle of loving friends and all the other things that you feel like you, in some manner, earn, deserve, you’re entitled to, oh, bummer, if that’s not the case. If that’s your response to the idea of there being no free will, by definition, you were one of the lucky ones.

For most people on earth, who were dealing with far less privilege, the notion that we are not the captains of our fate is, like, wildly liberating and humane. I mean, just ask someone who’s genetic profile and metabolism dooms them to obesity and being subject to a lifelong of unhappiness and societal stigma over that, and that’s just one of the billion ways in which the discovery that we’re nothing more or less than the biology over which we had no control and the environment over-, is great news, and is the most humane thing on Earth. All we spent is the last 500 years of scientific insights into seeing that people are not responsible for all sorts of things for which they used to be blamed or made to feel like they are inadequate or burnt at the stake for, and this is wonderfully liberating.

Timothy Revell: Yes, so I want to get into some of those implications, because, as you say, it’s, sort of, liberating to think, “Well, we’re just the products of our biology,” but at the same time, we’ve built a whole society around responsibility. That you have responsibilities to do certain things, but also, we have responsibility as society to hold people accountable for the decisions that they make, and these words are all, sort of, loaded with an intrinsic understanding of free will being baked into it.

Robert Sapolsky: Yes.

Timothy Revell: If everyone read your book overnight and agreed with you 100 per cent, what does a society look like where we accept this principle that free will does not exist?

Robert Sapolsky: Well, I think the first thing to emphasise is the roof isn’t going to cave in, because over and over and over, we have subtracted responsibility out of our views of human behaviour in the natural world, and it’s been okay. People haven’t run amok, society hasn’t, you know, gone to hell, at that point, because 400 years ago, we figured out hailstorms are not caused by witches and, like, old crones would not be held responsible for hailstorms and burnt at the stake. About 200 years ago, people figured out, definitely, that an epileptic seizure is not a sign of demonic possession. Responsibility is subtracted out.

About 50 years ago, the damn physiatrics, sort of, old boy oligarchy figured out that schizophrenia is not caused by mothers with psychodynamic hatred of their child, and instead, it’s a neurogenetic disorder. 30 years ago, we figured out that kids at school that simply are not learning to read, it’s not because they’re lazy and unmotivated, it’s because their cortical abnormalities are making them reverse letters that have, like, closed loops in them or whatever. We’ve done it over and over and over, and things have been just fine, and in fact, things have gotten much better and much more humane.

So, the challenge is to just imagine what things people a century from now will be saying about our time period and things we still thought were volitional and things that we punished people for and things that we rewarded people for, where there was absolutely no basis for it. More practically, like, how are we supposed to function? It seems like the first, sort of, thing to get off the table is, “Oh my God, we’re all going to run amok, because people will be unconstrained by, you know, “I can’t be held responsible.”

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Really careful studies suggest that people won’t run amok. Some pretty superficial ones say that, as soon as you prime people physiologically to believe less in free will, they start cheating like mad on their economic games, two minutes later, but, sort if, deeper studies show that that’s really not the case, and there’s a great parallel example. Instead of thinking, “Wow, I can do whatever I want, because I’m not responsible for my actions,” thinking, “Wow, I can do whatever I want because I won’t be held responsible in an ultimate sense.” Atheists are, if anything, more ethical in their behaviour than the highly religious. The running amok thing is not a worry.

The next one that’s got to be disposed of is, like nonetheless, dangerous people need to be contained and, yes, absolutely. Just because someone is not responsible for them being a damaging person, because they’ve been damaged as hell, like all of the rotten luck they’ve gotten, adversity in life, that doesn’t mean, you know, you shouldn’t constrain them from damaging. What people emphasise more and more is a quarantine model. Like, if somebody is infectious, through no fault of their own, they’re quarantined.

If a car’s breaks don’t work and it will run you over, keep it in a garage. If a person’s frontal cortex has been so done in by childhood trauma that they can’t regulate their emotional behaviours, make sure they can’t damage people. Make sure if all of that can strain them with the absolute minimum needed to prevent that and not an inch more in the name of retribution or rotten souls or anything that they deserve. And, as the flip side of it, like recognise that some people are better brain surgeons are better basketball players or something than others and that’s great. We really do want to have competent brain surgeons and I presume basketball players out there and they should be doing that stuff but don’t tell that they’re entitled to a greater salary than anyone else and don’t give them a greater salary. The meritocracy makes as little sense as does the criminal justice system when you really think about this.

Timothy Revell: Yes, it’s very interesting that as you present the things from history and you reel through them. Things like the not believing that people are influencing hail storms or that you’re-, in some way it’s a sign of the devil if you have epilepsy or the same with dyslexia. Those things feel so obvious to us now sitting here and I think that the vast majority of people will go of course it’s ridiculous we ever thought anything else but yet when you say for the criminal justice system it needs to be reframed so that it is no longer about responsibility but instead about quarantine I think there are lots of people who maybe have a harder time reaching that same conclusion. Is that what you find? That when you talk to people-, so historical examples that all makes sense but maybe the next step just seems almost unfathomable.

Robert Sapolsky: Exactly, and the real challenge is to think back that somewhere, I don’t know, 400 years ago there was some very learned, reflective, compassionate, empathic, introspective smart guy who is some sort of judge or something, and he believed in helping the underdog. And if there had been national public radio then to contribute money to, he would’ve done that and gotten a little button saying, “I support, like, everything they believe in.” He would’ve been like a total bleeding heart liberal of the time, and he’d come home at the end of the day and say, “Wow, tough day. We had this guy. Had to burn him at the stake. Had seizures. He obviously welcomed in Satan, I mean, kids. He had a wife, kids who were really upset. It was, like, hard to do but what can you do?” Nobody told him to welcome in Satan, so of course, we had to burn him at the stake, but tough day. And that would’ve been a compassionate liberal at the time and it would’ve been inconceivable then in the same way that it’s inconceivable now that somebody’s IQ or somebody’s capacity to master tough difficult things or somebody’s inability to regulate their emotions and thus be really damaging makes just as little sense.

Timothy Revell: Can you talk us through a little bit about that because quite a lot of those historical examples there about-, sort of, parts of the human condition becoming medicalized, us appreciating that their diseases or conditions that are really affecting things that happened to people. For example them having seizures but when it comes to crime I think some people will not see the immediate link there. So if you have someone who has committed a crime, how does the medical side of this, the neuroscience, all of that, fit into the point where they commit a crime?

Robert Sapolsky: Well, the examples you bring up first are the easy ones or the edge cases. Society is pretty good at recognising, at least in the American legal system, that if somebody has a sufficiently low IQ they shouldn’t be held legally responsible for a violent act or whatever. There’s, like, a cut off and people fight over what the cut off should be and all of that. If someone has had massive damage to their frontal cortex or a tumour there, I don’t know, about half the states in the United States are willing to say, in this edge case, there was not actually responsibility.

But yes, then we get to the normative range of like people doing awful stuff or people doing commendable stuff, where there isn’t an obvious whatever that presents, you know, this is a special mitigating case. There’s no special mitigating cases because it’s a continuum of the exact same biology. The second you can show stuff like what a paper a couple of years ago showed which is brain imaging on fetuses that by the time you’re a third trimester fetus the social economic status of your parents are already influencing the rate in which your brain is growing. By the time you can take kids and adolescence and show like a formal checklist of childhood adversaries and traumas, what somebody’s score is on this scale.

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The ace score, adverse child experience score. Like, we had a score from zero to ten depending on just how unlucky and awful your childhood was and for every additional point you get on the scale there’s about a 35 per cent increase chance that a guy by age 20 will have done something antisocial and violent. There’s about 35 per cent increase change that a female will have had a teen pregnancy of either unsafe sex, of by adulthood, a major mood disorder like anxiety or depression. If you can show that one extra step, whoa. Not only were they sexually abused as a kid but somebody in the family was incarcerated. That one extra point makes him 35 per cent more likely to be that way as an adult. You’re looking at what has to come into any of these factors which is we’ve just scratched the service on the things that move you from a 35 per cent chance of a particular outcome to a 100 per cent chance. And what I endlessly go on about is, like, ace scores adverse childhood experience scores.

You can have the exact same conclusion if there was such a thing as, like, RLCE ridiculously lucky child who experiences and you can get a whole scale on that. Did your parents read books to you? Did you, like, play and laugh a lot? Did you never wonder where your next meal was coming from? And no doubt for every one of those a 35 per cent increase chance that you’re going to have the corner office in some corporation some day. Like, you look at those and any of these myths of somebody being responsible ultimately for the bad or the good just isn’t supportable and eventually is morally repugnant as well.

Timothy Revell: I think for many-, like for me certainly when reading the book, I can accept all of that but part of me also wants to think but I’m different. There’s a certain sense of-, like, I totally understand that if you’ve gone through these horrible life experiences that is of course going to affect you later in life but it’s so hard to drop that idea that maybe I would make different choices but I think it is quite compelling that argument you put forward that I think would it be fair to say it boils down to if you had the same life experiences and you had the same biology you would do the same things.

Robert Sapolsky: Exactly. And feel the same sense of agency and captain of your fate, sort of, delusions. Something I try to emphasise though throughout the book is this is incredibly difficult to think this way. Like, I’ve believed this since I was, like, early adolescence and 99 per cent of the time I can’t manage to pull this off.

I think I recount in there a few years back there was some, like, appalling hate crime. Some guy showed up with an automatic weapon in a place of worship and killed a bunch of people and listening to the radio that next Monday morning saying whoever is being arraigned and is going to be charged with a federal hate crime as well which makes him eligible for the death penalty. I thought, “Yes. Fry the bastard.” Wait. I’m working on death penalty cases right now to convince juries that-, yet no one says this is going to be easy.

I’m terrible at it 99 per cent of the time. Not only am I violating my intellectual beliefs but my moral beliefs as well because these are really strong reflexes to both get pissed off at people who do awful things but in addition probably more fundamentally to feel, kind of, good about yourself if someone says well nice job on that. Yes. I did a nice job. I’m entitled to that praise. This is going to be incredibly hard but we’ve done it over and over and over again and it’s not that hard to identify the corners of society where it’s most important to make that emphasis first.

Timothy Revell: You hinted at it there but can you talk a little bit about your direct experience with the criminal justice system where you have appeared as a, sort of, expert on the brain. What has your role been there and how does it play into all of this?

Robert Sapolsky: Oh, this has been this little, minor hobby of working with what are called public defenders, who are the people who are assigned when some defendant can’t afford their own attorney, and this is a whole world of, like, liberal, do-gooder attorneys who lose 95 per cent of their cases. I’ve been working on a bunch of these, and what has always been the scenario is this is someone who has done something very, very bad. And where, initially, they were threatened and did something that could pass as self-defence, they stabbed the guy before the other guy could stab them who came at them first and they’re then lying there on the ground incapacitated and ten seconds later they come back and stab the guy an additional 72 times.

At which point the jury says well, you know, the first stab was self defence but 10 seconds that was enough time to premeditate and figure out that the threat was over with. But whoa, 72 additional times. That counts as premeditated murder and it’s always that, sort of, scenario and it is always somebody who was already virtually guaranteed to do this by the time they were 5 years old. Substance abuse at home, psychological abuse, physical abuse, sexual abuse, prenatal exposure drugs of abuse, shuttled through foster homes. Stabbed for the first time at age 10, you know, that repeated concussive head traumas from people abusing them, all of that and you look at someone like that and this is screamingly this is a broken machine.

Why are we conscious? The answer lies in other animals’ heads

The thing that I always do with these juries is take them through, like, what’s going on in the brain when you make a decision and how we’re much more likely neurobiologically to make an awful decision if we’re under a whole lot of stress. Like somebody coming at us with a knife and we’re a gazillion times more likely to make the wrong decision during that 10 seconds if we have a brain that’s been pickled in adversity from day one because your brain would’ve been constructed in a way where you’re going to make a terrible impulsive decision at that point and then I dramatically look at the jury and say the same thing you said before which is if they had gone through this fetal life childhood etc, etc, all the things that-, they would’ve done the exact same thing and the juries all nod and look like they’re following and then they go into the jury room and they look at the pictures of the corpse with the head almost decapitated from stabs number 36 through 43 or something out of the 72 and they vote to convict the guy. I’ve done 12 of these trials by now over the years and we’ve lost 11 of them and that’s even arguing, like, the edge cases. Wow, this is a guy whose frontal cortex was destroyed in a car accident when he was eight.

He spent two months in a coma, came out of it, no prior history whatever and did his first murder at age 12 and here you guys have just convicted him of his 8th and 9th murders and he’s a broken machine. And you know, they go and sit about it for a while and they come back with the death penalty so it’s a real uphill battle even with these edge cases of, whoa, traumatic examples of, like, terrible like or then look at like, Ivy League students or my undergrads at Stanford and look at their histories and you know by age 5 they already had their paths set to have a higher of an average income sometime later and would go to a prestigious college and the same exact thing. It’s very hard to just work with the gears that made them who they are.

Timothy Revell: Alright, one last question for you. What are you planning on tackling next? Is it the meaning of life?

Robert Sapolsky: Oh, I don’t know. I hope something interesting comes along, building on-, not to get all preachy and stuff, but at the end of the day this stops being an issue for neuroscientists or behaviour geneticists or early childhood develop-, and it becomes a social justice issue. It’s really great, philosophically, if people believe less in free will and all of that. The number of people on earth who are made to suffer because of the miserable luck in their life, starting with their ancestors picking the wrong, god-awful corner of the planet to live in, and centuries later, that has something to do with this person’s cerebral malaria when they were five.

The social justice aspects of this, at the end of the day, are really the things that matter most about this, because we have a constructed a world with an awful lot of myths of free will, and culpability and responsibility. And most people who don’t have the corner office in their, like, fancy corporation, most people have mostly suffered because of this so that’s, kind of, the end that is galvanising me the most at this point. At the end of the day, that’s what this stuff is really about.

Timothy Revell: So, what did you think? It’s a pretty compelling case that Sapolsky built I think that free will doesn’t exist and as he puts it in the book “We are not captains of our ships. Our ships never had captains.” And if we could really accept that the implications that would have for our society would be profound. If you have any thoughts on this do please get in touch at podcasts at new scientist.com. We would love to hear from you and if you enjoy our podcast do please leave a review on whatever platform you’re listening to us on. It does really help us out .That’s it for this episode of culture lab. We’ll be back in a couple of weeks time with some more. That’s bye for now. 

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A Stanford professor says science shows free will doesn’t exist. Here’s why he’s mistaken

Research Associate, Institute for Ethics and Society, University of Notre Dame Australia

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It seems like we have free will. Most of the time, we are the ones who choose what we eat, how we tie our shoelaces and what articles we read on The Conversation.

However, the latest book by Stanford neurobiologist Robert Sapolsky, Determined: A Science of Life Without Free Will, has been receiving a lot of media attention for arguing science shows this is an illusion .

Sapolsky summarises the latest scientific research relevant to determinism: the idea that we’re causally “determined” to act as we do because of our histories – and couldn’t possibly act any other way.

According to determinism, just as a rock that is dropped is determined to fall due to gravity, your neurons are determined to fire a certain way as a direct result of your environment, upbringing, hormones, genes, culture and myriad other factors outside your control. And this is true regardless of how “free” your choices seem to you.

Sapolsky also says that because our behaviour is determined in this way, nobody is morally responsible for what they do. He believes while we can lock up murderers to keep others safe, they technically don’t deserve to be punished.

This is quite a radical position. It’s worth asking why only 11% of philosophers agree with Sapolsky, compared with the 60% who think being causally determined is compatible with having free will and being morally responsible.

Have these “ compatibilists ” failed to understand the science? Or has Sapolsky failed to understand free will?

Read more: Science communicators need to stop telling everybody the universe is a meaningless void

Is determinism incompatible with free will?

“Free will” and “responsibility” can mean a variety of different things depending on how you approach them.

Many people think of free will as having the ability to choose between alternatives. Determinism might seem to threaten this, because if we are causally determined then we lack any real choice between alternatives; we only ever make the choice we were always going to make.

But there are counterexamples to this way of thinking. For instance, suppose when you started reading this article someone secretly locked your door for 10 seconds, preventing you from leaving the room during that time. You, however, had no desire to leave anyway because you wanted to keep reading – so you stayed where you are. Was your choice free?

Many would argue even though you lacked the option to leave the room, this didn’t make your choice to stay unfree. Therefore, lacking alternatives isn’t what decides whether you lack free will. What matters instead is how the decision came about.

The trouble with Sapolsky’s arguments, as free will expert John Martin Fischer explains , is he doesn’t actually present any argument for why his conception of free will is correct.

He simply defines free will as being incompatible with determinism, assumes this absolves people of moral responsibility, and spends much of the book describing the many ways our behaviours are determined. His arguments can all be traced back to his definition of “free will”.

Compatibilists believe humans are agents. We live lives with “meaning”, have an understanding of right and wrong, and act for moral reasons. This is enough to suggest most of us, most of the time, have a certain type of freedom and are responsible for our actions (and deserving of blame) – even if our behaviours are “determined”.

Compatibilists would point out that being constrained by determinism isn’t the same as being constrained to a chair by a rope. Failing to save a drowning child because you were tied up is not the same as failing to save a drowning child because you were “determined” not to care about them. The former is an excuse. The latter is cause for condemnation.

Incompatibilists must defend themselves better

Some readers sympathetic to Sapolsky might feel unconvinced. They might say your decision to stay in the room, or ignore the child, was still caused by influences in your history that you didn’t control – and therefore you weren’t truly free to choose.

However, this doesn’t prove that having alternatives or being “undetermined” is the only way we can count as having free will. Instead, it assumes they are. From the compatibilists’ point of view, this is cheating.

Compatibilists and incompatibilists both agree that, given determinism is true, there is a sense in which you lack alternatives and could not do otherwise.

However, incompatibilists will say you therefore lack free will, whereas compatibilists will say you still possess free will because that sense of “lacking alternatives” isn’t what undermines free will – and free will is something else entirely.

They say as long as your actions came from you in a relevant way (even if “you” were “determined” by other things), you count as having free will. When you’re tied up by a rope, the decision to not save the drowning child doesn’t come from you. But when you just don’t care about the child, it does.

By another analogy, if a tree falls in a forest and nobody is around, one person may say no auditory senses are present, so this is incompatible with sound existing. But another person may say even though no auditory senses are present, this is still compatible with sound existing because “sound” isn’t about auditory perception – it’s about vibrating atoms.

Both agree nothing is heard, but disagree on what factors are relevant to determining the existence of “sound” in the first place. Sapolsky needs to show why his assumptions about what counts as free will are the ones relevant to moral responsibility. As philosopher Daniel Dennett once put it, we need to ask which “ varieties of free will [are] worth wanting ”.

Free will isn’t a scientific question

The point of this back and forth isn’t to show compatibilists are right. It is to highlight there’s a nuanced debate to engage with. Free will is a thorny issue. Showing nobody is responsible for what they do requires understanding and engaging with all the positions on offer. Sapolsky doesn’t do this.

Sapolsky’s broader mistake seems to be assuming his questions are purely scientific: answered by looking just at what the science says. While science is relevant, we first need some idea of what free will is (which is a metaphysical question ) and how it relates to moral responsibility (a normative question ). This is something philosophers have been interrogating for a very long time .

Interdisciplinary work is valuable and scientists are welcome to contribute to age-old philosophical questions. But unless they engage with existing arguments first, rather than picking a definition they like and attacking others for not meeting it, their claims will simply be confused.

Read more: Curious Kids: what is the most important thing a scientist needs?

• Determinism
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• The science of free will

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November 1, 2011

Is Free Will an Illusion?

Don't trust your instincts about free will or consciousness, experimental philosophers say

By Shaun Nichols

IT SEEMS OBVIOUS to me that I have free will . When I have just made a decision, say, to go to a concert, I feel that I could have chosen to do something else. Yet many philosophers say this instinct is wrong. According to their view, free will is a figment of our imagination. No one has it or ever will. Rather our choices are either determined—necessary outcomes of the events that have happened in the past—or they are ­random.

Our intuitions about free will, however, challenge this nihilistic view. We could, of course, simply dismiss our intuitions as wrong. But psychology suggests that doing so would be premature: our hunches often track the truth pretty well [see “ The Powers and Perils of Intuition ,” by David G. Myers; Scientific American Mind , June/July 2007]. For example, if you do not know the answer to a question on a test, your first guess is more likely to be right. In both philosophy and science, we may feel there is something fishy about an argument or an experiment before we can identify exactly what the problem is.

The debate over free will is one example in which our intuitions conflict with scientific and philosophical arguments. Something similar holds for intuitions about consciousness, morality, and a host of other existential concerns. Typically philosophers deal with these issues through careful thought and discourse with other theorists. In the past decade, however, a small group of philosophers have adopted more data-driven methods to illuminate some of these confounding questions. These so-called experimental philosophers administer surveys, measure reaction times and image brains to understand the sources of our instincts. If we can figure out why we feel we have free will, for example, or why we think that consciousness consists of something more than patterns of neural activity in our brain, we might know whether to give credence to those feelings. That is, if we can show that our intuitions about free will emerge from an untrustworthy process, we may decide not to trust those beliefs.

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Unknown Influences To discover the psychological basis for philosophical problems, experimental philosophers often survey people about their views on charged issues. For instance, scholars have argued about whether individuals actually believe that their choices are independent of the past and the laws of nature. Experimental philosophers have tried to resolve the debate by asking study participants whether they agree with descriptions such as the following:

Imagine a universe in which everything that happens is completely caused by whatever happened before it. So what happened in the beginning of the universe caused what happened next and so on, right up to the present. If John decided to have french fries at lunch one day, this decision, like all others, was caused by what happened before it.

When surveyed, Americans say they disagree with such descriptions of the universe . From inquiries in other countries, researchers have found that Chinese, Colombians and Indians share this opinion: individual choice is not determined. Why do humans hold this view? One promising explanation is that we presume that we can generally sense all the influences on our decision making—and because we cannot detect deterministic influences, we discount them.

Of course, people do not believe they have conscious access to everything in their mind. We do not presume to intuit the causes of headaches, memory formation or visual processing. But research indicates that people do think they can access the factors affecting their choices.

Yet psychologists widely agree that unconscious processes exert a powerful influence over our choices. In one study, for example, participants solved word puzzles in which the words were either associated with rudeness or politeness. Those exposed to rudeness words were much more likely to interrupt the experimenter in a subsequent part of the task. When debriefed, none of the subjects showed any awareness that the word puzzles had affected their behavior. That scenario is just one of many in which our decisions are directed by forces lurking beneath our awareness.

Thus, ironically, because our subconscious is so powerful in other ways, we cannot truly trust it when considering our notion of free will. We still do not know conclusively that our choices are determined. Our intuition, however, provides no good reason to think that they are not. If our instinct cannot support the idea of free will, then we lose our main rationale for resisting the claim that free will is an illusion.

Is Consciousness Just a Brain Process? Though a young movement, experimental philosophy is broad in scope. Its proponents apply their methods to varied philosophical problems, including questions about the nature of the self. For example, what (if anything) makes you the same person from childhood to adulthood? They investigate issues in ethics, too: Do people think that morality is objective, as is mathematics, and if so, why? Akin to the question of free will, they are also tackling the dissonance between our intuitions and scientific theories of consciousness.

Scientists have postulated that consciousness is populations of neurons firing in certain brain areas, no more and no less. To most people, however, it seems bizarre to think that the distinctive tang of kumquats, say, is just a pattern of neural activation.

Our instincts about consciousness are triggered by specific cues, experimental philosophers explain, among them the existence of eyes and the appearance of goal-directed behavior, but not neurons. Studies indicate that people’s intuitions tell them that insects—which, of course, have eyes and show goal-directed behavior—can feel happiness, pain and anger.

The problem is that insects very likely lack the neural wherewithal for these sensations and emotions. What is more, engineers have programmed robots to display simple goal-directed behaviors, and these robots can produce the uncanny impression that they have feelings, even though the machines are not remotely plausible candidates for having awareness. In short, our instincts can lead us astray on this matter, too. Maybe consciousness does not have to be something different from—or above and beyond—brain processes.

Philosophical conflicts over such concepts as free will and consciousness often have their roots in ordinary intuitions, and the historical debates often end in stalemates. Experimental philosophers maintain that we can move past some of these impasses if we understand the nature of our gut feelings. This nascent field will probably not produce a silver bullet to fully restore or discredit our beliefs in free will and other potential illusions. But by understanding why we find certain philosophical views intuitively compelling, we might find ourselves in a position to recognize that, in some cases, we have little reason to hold onto our hunches.

Chapter 5: The problem of free will and determinism

The problem of free will and determinism

Matthew Van Cleave

“You say: I am not free. But I have raised and lowered my arm. Everyone understands that this illogical answer is an irrefutable proof of freedom.”

-Leo Tolstoy

“Man can do what he wills but he cannot will what he wills.”

-Arthur Shopenhauer

“None are more hopelessly enslaved than those who falsely believe they are free.”

-Johann Wolfgang von Goethe

The term “freedom” is used in many contexts, from legal, to moral, to psychological, to social, to political, to theological. The founders of the United States often extolled the virtues of “liberty” and “freedom,” as well as cautioned us about how difficult they were to maintain. But what do these terms mean, exactly? What does it mean to claim that humans are (or are not) free? Almost anyone living in a liberal democracy today would affirm that freedom is a good thing, but they almost certainly do not all agree on what freedom is. With a concept as slippery as that of free will, it is not surprising that there is often disagreement. Thus, it will be important to be very clear on what precisely we are talking about when we are either affirming or denying that humans have free will. There is an important general point here that extends beyond the issue of free will: when debating whether or not x exists, we must first be clear on defining x, otherwise we will end up simply talking past each other . The philosophical problem of free will and determinism is the problem of whether or not free will exists in light of determinism. Thus, it is crucial to be clear in defining what we mean by “free will” and “determinism.” As we will see, these turn out to be difficult and contested philosophical questions. In this chapter we will consider these different positions and some of the arguments for, as well as objections to, them.

Let’s begin with an example. Consider the 1998 movie, The Truman Show . In that movie the main character, Truman Burbank (played by Jim Carrey), is the star of a reality television show. However, he doesn’t know that he is. He believes he is just an ordinary person living in an ordinary neighborhood, but in fact this neighborhood is an elaborate set of a television show in which all of his friends and acquaintances are just actors. His every moment is being filmed and broadcast to a whole world of fans that he doesn’t know exists and almost every detail of his life has been carefully orchestrated and controlled by the producers of the show. For example, Truman’s little town is surrounded by a lake, but since he has been conditioned to believe (falsely) that he had a traumatic boating accident in which his father died, he never has the desire to leave the small little town and venture out into the larger world (at least at first). So consider the life of Truman as described above. Is he free or not? On the one hand, he gets to do pretty much everything he wants to do and he is pretty happy. Truman doesn’t look like he’s being coerced in any explicit way and if you asked him if he was, he would almost certain reply that he wasn’t being coerced and that he was in charge of his life. That is, he would say that he was free (at least to the same extent that the rest of us would). These points all seem to suggest that he is free. For example, when Truman decides that he would rather not take a boat ride out to explore the wider world (which initially is his decision), he is doing what he wants to do. His action isn’t coerced and does not feel coerced to him. In contrast, if someone holds a gun to my head and tells me “your wallet or your life!” then my action of giving him my wallet is definitely coerced and feels so.

On the other hand, it seems clear the Truman’s life is being manipulated and controlled in a way that undermines his agency and thus his freedom. It seems clear that Truman is not the master of his fate in the way that he thinks he is. As Goethe says in the epigraph at the beginning of this chapter, there’s a sense in which people like Truman are those who are most helplessly enslaved, since Truman is subject to a massive illusion that he has no reason to suspect. In contrast, someone who knows she is a slave (such as slaves in the antebellum South in the United States) at least retains the autonomy of knowing that she is being controlled. Truman seems to be in the situation of being enslaved and not knowing it and it seems harder for such a person to escape that reality because they do not have any desire to (since they don’t know they are being manipulated and controlled).

As the Truman Show example illustrates, it seems there can be reasonable disagreement about whether or not Truman is free. On the one hand, there’s a sense in which he is free because he does what he wants and doesn’t feel manipulated. On the other hand, there’s a sense in which he isn’t free because what he wants to do is being manipulated by forces outside of his control (namely, the producers of the show). An even better example of this kind of thing comes from Aldous Huxley’s classic dystopia, Brave New World . In the society that Huxley envisions, everyone does what they want and no one is ever unhappy. So far this sounds utopic rather than dystopic. What makes it dystopic is the fact that this state of affairs is achieved by genetic and behavioral conditioning in a way that seems to remove any choice. The citizens of the Brave New World do what they want, yes, but they seems to have absolutely no control over what they want in the first place. Rather, their desires are essentially implanted in them by a process of conditioning long before they are old enough to understand what is going on. The citizens of Brave New World do what they want, but they have no control over what the want in the first place. In that sense, they are like robots: they only have the desires that are chosen for them by the architects of the society.

So are people free as long as they are doing what they want to—that is, choosing the act according to their strongest desires? If so, then notice that the citizens of Brave New World would count as free, as would Truman from The Truman Show , since these are both cases of individuals who are acting on their strongest desires. The problem is that those desires are not desires those individuals have chosen. It feels like the individuals in those scenarios are being manipulated in a way that we believe we aren’t. Perhaps true freedom requires more than just that one does what one most wants to do. Perhaps true freedom requires a genuine choice. But what is a genuine choice beyond doing what one most wants to do?

Philosophers are generally of two main camps concerning the question of what free will is. Compatibilists believe that free will requires only that we are doing what we want to do in a way that isn’t coerced—in short, free actions are voluntary actions. Incompatibilists , motivated by examples like the above where our desires are themselves manipulated, believe that free will requires a genuine choice and they claim that a choice is genuine if and only if, were we given the choice to make again, we could have chosen otherwise . I can perhaps best crystalize the difference between these two positions by moving to a theological example. Suppose that there is a god who created the universe, including humans, and who controls everything that goes on in the universe, including what humans do. But suppose that god does this not my directly coercing us to do things that we don’t want to do but, rather, by implanting the desire in us to do what god wants us to do. Thus human beings, by doing what the want to do, would actually be doing what god wanted them to do. According to the compatibilist, humans in this scenario would be free since they would be doing what they want to do. According to the incompatibilist, however, humans in this scenario would not be free because given the desire that god had implanted in them, they would always end up doing the same thing if given the decision to make (assuming that desires deterministically cause behaviors). If you don’t like the theological example, consider a sci-fi example which has the same exact structure. Suppose there is an eccentric neuroscientist who has figured out how to wire your brain with a mechanism by which he can implant desire into you.

Suppose that the neuroscientist implants in you the desire to start collecting stamps and you do so. However, you know none of this (the surgery to implant the device was done while you were sleeping and you are none the wiser).

From your perspective, one day you find yourself with the desire to start collecting stamps. It feels to you as though this was something you chose and were not coerced to do. However, the reality is that given this desire that the neuroscientist implanted in you, you could not have chosen not to have started collecting stamps (that is, you were necessitated to start collecting stamps, given the desire). Again, in this scenario the compatibilist would say that your choice to start collecting stamps was free (since it was something you wanted to do and did not feel coerced to you), but the incompatibilist would say that your choice was not free since given the implantation of the desire, you could not have chosen otherwise.

We have not quite yet gotten to the nub of the philosophical problem of free will and determinism because we have not yet talked about determinism and the problem it is supposed to present for free will. What is determinism?

Determinism is the doctrine that every cause is itself the effect of a prior cause. More precisely, if an event (E) is determined, then there are prior conditions (C) which are sufficient for the occurrence of E. That means that if C occurs, then E has to occur. Determinism is simply the claim that every event in the universe is determined. Determinism is assumed in the natural sciences such as physics, chemistry and biology (with the exception of quantum physics for reasons I won’t explain here). Science always assumes that any particular event has some law-like explanation—that is, underlying any particular cause is some set of law- like regularities. We might not know what the laws are, but the whole assumption of the natural sciences is that there are such laws, even if we don’t currently know what they are. It is this assumption that leads scientists to search for causes and patterns in the world, as opposed to just saying that everything is random. Where determinism starts to become contentious is when we move into the human sciences, such as psychology, sociology, and economics. To illustrate why this is contentious, consider the famous example of Laplace’s demon that comes from Pierre-Simon Laplace in 1814:

We may regard the present state of the universe as the effect of its past and the cause of its future. An intellect which at a certain moment would know all forces that set nature in motion, and all positions of all items of which nature is composed, if this intellect were also vast enough to submit these data to analysis, it would embrace in a single formula the movements of the greatest bodies of the universe and those of the tiniest atom; for such an intellect nothing would be uncertain and the future just like the past would be present before its eyes.

Laplace’s point is that if determinism were true, then everything that every happened in the universe, including every human action ever undertaken, had to have happened. Of course humans, being limited in knowledge, could never predict everything that would happen from here out, but some being that was unlimited in intelligence could do exactly that. Pause for a moment to consider what this means. If determinism is true, then Laplace’s demon would have been able to predict from the point of the big bang, that you would be reading these words on this page at this exact point of time. Or that you had what you had for breakfast this morning. Or any other fact in the universe. This seems hard to believe, since it seems like some things that happen in the universe didn’t have to happen. Certain human actions seem to be the paradigm case of such events. If I ate an omelet for breakfast this morning, that may be a fact but it seems strange to think that this fact was necessitated as soon as the big bang occurred. Human actions seem to have a kind of independence from web of deterministic web of causes and effects in a way that, say, billiard balls don’t.

Given that the cue ball his the 8 ball with a specific velocity, at a certain angle, and taking into effect the coefficient of friction of the felt on the pool table, the exact location of the 8 ball is, so to speak, already determined before it ends up there. But human behavior doesn’t seem to be like the behavior of the 8 ball in this way, which is why some people think that the human sciences are importantly different than the natural sciences. Whether or not the human sciences are also deterministic is an issue that helps distinguish the different philosophical positions one can take on free will, as we will see presently. But the important point to see right now is that determinism is a doctrine that applies to all causes, including human actions. Thus, if some particular brain state is what ultimately caused my action and that brain state itself was caused by a prior brain state, and so on, then my action had to occur given those earlier prior events. And that entails that I couldn’t have chosen to act otherwise, given that those earlier events took place . That means that the incompatibilist position on free will cannot be correct if determinism is true. Recall that incompatibilism requires that a choice is free only if one could have chosen differently, given all the same initial conditions. But if determinism is true, then human actions are no different than the 8 ball: given what has come before, the current event had to happen. Thus, if this morning I cooked an omelet, then my “choice” to make that omelet could not have been otherwise. Given the complex web of prior influences on my behavior, my making that omelet was determined. It had to occur.

Of course, it feels to us, when contemplating our own futures, that there are many different possible ways our lives might go—many possible choices to be made. But if determinism is true, then this is an illusion. In reality, there is only one way that things could go, it’s just that we can’t see what that is because of our limited knowledge. Consider the figure below. Each junction in the figure below represents a decision I make and let’s suppose that some (much larger) decision tree like this could represent all of the possible ways my life could go. At any point in time, when contemplating what to do, it seems that I can conceive of my life going many different possible ways. Suppose that A represents one series of choices and B another. Suppose, further, that A represents what I actually do (looking backwards over my life from the future). Although from this point in time it seems that I could also have made the series of choices represented in B, if determinism is true then this is false. That is, if A is what ends up happening, then A is the only thing that ever could have happened . If it hasn’t yet hit you how determinism conflicts with our sense of our own possibilities in life, think about that for a second.

As the foregoing I hope makes clear, the incompatibilist definition of free will is incompatibile with determinism (that’s why it’s called “incompatibilist”). But that leaves open the question of which one is true. To say that free will and determinism are logically incompatible is just to say that they cannot both be true, meaning that one or the other must be false. But which one? Some will claim that it is determinism which is false. This position is called libertarianism (not to be confused with political libertarianism, which is a totally different idea). Others claim that determinism is true and that, therefore, there is no free will. This position is called hard determinism. A third type of position, compatibilism , rejects the incompatibilist definition of freedom and claims that free will and determinism are compatible (hence the name). The table below compares these different positions. But which one is correct? In the remainder of the chapter we will consider some arguments for and against these three positions on free will and determinism.

Libertarianism

Both libertarianism and hard determinism accept the following proposition: If determinism is true, then there is no free will. What distinguishes libertarianism from hard determinism is the libertarian’s claim that there is free will. But why should we think this? This question is especially pressing when we recognize that we assume a deterministic view in many other domains in life. When you have a toothache, we know that something must have caused that toothache and whatever cause that was, something else must have caused that cause. It would be a strange dentist who told you that your toothache didn’t have a cause but just randomly occurred. When the weather doesn’t go as the meteorologist predicts, we assume there must be a cause for why the weather did what it did. We might not ever know the cause in all its specific details, but assume there must be one. In cases like meteorology, when our scientific predictions are wrong, we don’t always go back and try to figure out what the actual causes were—why our predictions were wrong. But in other cases we do. Consider the explosion of the Space Shuttle Challenger in 1986. Years later it was finally determined what led to that explosion (“O-ring” seals that were not designed for the colder condition of the launch). There’s a detailed deterministic physical explanation that one could give of how the failure of those O-rings led to the explosion of the Challenger. In all of these cases, determinism is the fundamental assumption and it seems almost nothing could overturn it.

But the libertarian thinks that the domain of human action is different than every other domain. Humans are somehow able to rise above all of the influences on them and make decisions that are not themselves determined by anything that precedes them. The philosopher Roderick Chisholm accurately captured the libertarian position when he claimed that “we have a prerogative which some would attribute only to God: each of us, when we really act, is a prime mover unmoved. In doing what we do, we cause certain events to happen, and nothing and no one, except we ourselves, causes us to cause those events to happen” (Chisholm, 1964). But why should we think that we have such a godlike ability? We will consider two arguments the libertarian makes in support of her position: the argument from intuitions and the argument from moral responsibility.

The argument from intuitions is based on the very strong intuition that there are some things that we have control over and that nothing causes us to do those things except for our own willing them. The strongest case for this concerns very simple actions, such as moving one’s finger. Suppose that I hold up my index finger and say that I am going to move it to the right or the to the left, but that I have not yet decided which way to move it. At the moment before I move my finger one way or the other, it truly seems to me that my future is open.

Nothing in my past and nothing in my present seems to be determining me to move my finger to the right or to the left. Rather, it seems to me that I have total control over what happens next. Whichever way I move my finger, it seems that I could have moved it the other way. So if, as a matter of fact, I move my finger to the right, it seems unquestionably true that I could have moved it to the left (and vice versa, mutatis mutandis ). Thus, in cases of simple actions like moving my finger to the right or left, it seems that the strong incompatibilist definition of freedom is met: we have a very strong intuition that no matter what I actually did, I could have chosen otherwise, were I to be given that exact choice again . The libertarian does not claim that all human actions are like this. Indeed, many of our actions (perhaps even ones that we think are free) are determined by prior causes. The libertarian’s claim is just that at least some of our actions do meet the incompatibilist’s definition of free and, thus, that determinism is not universally true.

The argument from moral responsibility is a good example of what philosophers call a transcendental argument . Transcendental arguments attempt to establish the truth of something by showing that that thing is necessary in order for something else, which we strongly believe to be true, to be true. So consider the idea that normally developed adult human beings are morally responsible for their actions. For example, if Bob embezzles money from his charity in order to help pay for a new sports car, we would rightly hold Bob accountable for this action. That is, we would punish Bob and would see punishment as appropriate. But a necessary condition of holding Bob responsible is that Bob’s action was one that he chose, one that he was in control of, one that he could have chosen not to do. Philosophers call this principle ought implies can : if we say that someone ought (or ought not) do something, this implies that they can do it (that is, they are capable of doing it). The ought implies can principle is consistent with our legal practices. For example, in cases where we believe that a person was not capable of doing the right thing, we no longer hold them morally or criminally liable. A good example of this within our legal system is the insanity defense: if someone was determined to be incapable of appreciating the difference between right and wrong, we do not find them guilty of a crime. But notice what determinism would do to the ought implies can principle. If everything we ever do had to happen (think Laplace’s demon), that means that Bob had to embezzle those funds and buy that sports car. The universe demanded it. That means he couldn’t not have done those things. But if that is so, then, by the ought implies can principle, we cannot say that he ought not to have done those things. That is, we cannot hold Bob morally responsible for those things. But this seems absurd, the libertarian will say.

Surely Bob was responsible for those things and we are right to hold him responsible. But the only we way can reasonably do this is if we assume that his actions were chosen—that he could have chosen to do otherwise than he in fact chose. Thus, determinism is incompatible with the idea that human beings are morally responsible agents. The practice of holding each other to be morally responsible agents doesn’t make sense unless humans have incompatibilist free will—unless they could have chosen to do otherwise than they in fact did. That is the libertarian’s transcendental argument from moral responsibility.

Hard determinism

Hard determinism denies that there is free will. The hard determinist is a “tough-minded” individual who bravely accepts the implication of a scientific view of the world. Since we don’t in general accept that there are causes that are not themselves the result of prior causes, we should apply this to human actions too. And this means that humans, contrary to what they might believe (or wish to believe) about themselves, do not have free will. As noted above, hard determininsm follows from accepting the incompatibilist definition of free will as well as the claim that determinism is universally true. One of the strongest arguments in favor of hard determinism is based on the weakness of the libertarian position. In particular, the hard determinist argues that accepting the existence of free will leaves us with an inexplicable mystery: how can a physical system initiate causes that are not themselves caused?

If the libertarian is right, then when an action is free it is such that given exactly the same events leading up to one’s action, one still could have acted otherwise than they did. But this seems to require that the action/choice was not determined by any prior event or set of events. Consider my decision to make a cheese omelet for breakfast this morning. The libertarian will say that my decision to make the cheese omelet was not free unless I could have chosen to do otherwise (given all the same initial conditions). But that means that nothing was determining my decision. But what kind of thing is a decision such that it causes my actions but is not itself caused by anything? We do not know of any other kind of thing like this in the universe. Rather, we think that any event or thing must have been caused by some (typically complex) set of conditions or events. Things don’t just pop into existence without being caused . That is as fundamental a principle as any we can think of. Philosophers have for centuries upheld the principle that “nothing comes from nothing.” They even have a fancy Latin phrase for it: ex nihilo nihil fir [1] . The problem is that my decision to make a cheese omelet seems to be just that: something that causes but is not itself caused. Indeed, as noted earlier, the libertarian Roderick Chisholm embraces this consequence of the libertarian position very clearly when he claimed that when we exercise our free will,

“we have a prerogative which some would attribute only to God: each of us, when we really act, is a prime mover unmoved. In doing what we do, we cause certain events to happen, and nothing and no one, except we ourselves, causes us to cause those events to happen” (Chisholm, 1964).

How could something like this exist? At this point the libertarian might respond something like this:

I am not claiming that something comes from nothing; I am just claiming that our decisions are not themselves determined by any prior thing. Rather, we ourselves, as agents, cause our decisions and nothing else causes us to cause those decisions (at least in cases where we have acted freely).

However, it seems that the libertarian in this case has simply pushed the mystery back one step: we cause our decisions, granted, but what causes us to make those decisions? The libertarian’s answer here is that nothing causes us. But now we have the same problem again: the agent is responsible for causing the decision but nothing causes the agent to make that decision. Thus we seem to have something coming from nothing. Let’s call this argument the argument from mysterious causes. Here’s the argument in standard form:

• The existence of free will implies that when an agent freely decides to do something, the agent’s choice is not caused (determined) by anything.
• To say that something has no cause is to violate the ex nihilo nihil fit principle.
• But nothing can violate the ex nihilo nihil fit principle.
• Therefore, there is no free will (from 1-3)

The hard determinist will make a strong case for premise 3 in the above argument by invoking basic scientific principles such as the law of conservation of energy, which says that the amount of energy within a closed system stays that same. That is, energy cannot be created or destroyed. Consider a billiard ball. If it is to move then it must get the required energy to do so from someplace else (typically another billiard ball knocking into it, the cue stick hitting it or someone tilting the pool table). To allow that something could occur without any cause—in this case, the agent’s decision—would be a violation of the conservation of energy principle, which is as basic a scientific principle as we know. When forced to choose between uphold such a basic scientific principle as this and believing in free will, the hard determinist opts for the former. The hard determinist will put the ball in the libertarian’s court to explain how something could come from nothing.

I will close this section by indicating how these problems in philosophy often ramify into other areas of philosophy. In the first place, there is a fairly common way that libertarians respond to the charge that their view violates basic principles such as ex nihilo nihil fit and, more specifically, the physical law of conservation of energy. Libertarians could claim that the mind is not physical—a position known in the philosophy of mind as “substance dualism” (see philosophy of mind chapter in this textbook for more on substance dualism). If the mind isn’t physical, then neither are our mental events, such our decisions.

Rather, all of these things are nonphysical entities. If decisions are nonphysical entities, there is at least no violation of the physical laws such as the law of conservation of energy. [2] Of course, if the libertarian were to take this route of defending her position, she would then need to defend this further assumption (no small task). In any case, my main point here is to see the way that responses to the problem of free well and determinism may connect with other issue within philosophy. In this case, the libertarian’s defense of free will may turn out to depend on the defensibility of other assumptions they make about the nature of the mind. But the libertarian is not the only one who will need to ultimately connect her account of free will up with other issues in philosophy. Since hard determinists deny that free will exists, it seems that they will owe us some account of moral responsibility. If, moral responsibility requires that humans have free will (see previous section), then in denying free will we seem to also be denying that humans have moral responsibility. Thus, hard determinists will face the objection that in rejecting free will they also destroy moral responsibility.

But since it seems we must hold individuals morally to account for certain actions (such as the embezzler from the previous section), the hard determinist

needs some account of how it makes sense to do this given that human being don’t have free will. My point here is not to broach the issue of how the hard determinist might answer this, but simply to show how hard determinist’s position on the problem of free will and determinism must ultimately connect with other issues in philosophy, such issues in metaethics [3] . This is a common thing that happens in philosophy. We may try to consider an issue or problem in isolation, but sooner or later that problem will connect up with other issues in philosophy.

Compatibilism

The best argument for compatibilism builds on a consideration of the difficulties with the incompatibilist definition of free will (which both the libertarian and the hard determinist accept). As defined above, compatibilists agree with the hard determinists that determinism is true, but reject the incompatibilist definition of free will that hard determinists accept. This allows compatbilists to claim that free will is compatible with determinism. Both libertarians and hard compatibilists tend to feel that this is somehow cheating, but the compatibilist attempts to convince us arguing that the strong incompatibilist definition of freedom is problematic and that only the weaker compatibilist definition of freedom—free actions are voluntary actions—will work. We will consider two objections that the compatibilist raises for the incompatibilist definition of freedom: the epistemic objection and the arbitrariness objection . Then we will consider the compatibilist’s own definition of free will and show how that definition fits better with some of our common sense intuitions about the nature of free actions.

The epistemic objection is that there is no way for us to ever know whether any one of our actions was free or not. Recall that the incompatibilist definition of freedom says that a decision is free if and only if I could have chosen otherwise than I in fact chose, given exactly all the same conditions. This means that if we were, so to speak, rewind the tape of time and be given that decision to make over again, we could have chosen differently. So suppose the question is whether my decision to make a cheese omelet for breakfast was free. To answer this question, we would have to know when I could have chosen differently. But how am I supposed to know that ? It seems that I would have to answer a question about a strange counterfactual : if given that decision to make over again, would I choose the same way every time or not? How on earth am I supposed to know how to answer that question? I could say that it seems to me that I could make a different decision regarding making the cheese omelet (for example, I could have decided to eat cereal instead), but why should I think that that is the right answer? After all, how things seem regularly turn out to be not the case—especially in science. The problem is that I don’t seem to have any good way of answering this counterfactual question of what I would choose if given the same decision to make over again. Thus the epistemic objection [4] is that since I have no way of knowing whether I would/wouldn’t make the same decision again, I can never know whether any of my actions are free.

The arbitrariness objection is that it turns our free actions into arbitrary actions. And arbitrary actions are not free actions. To see why, consider that if the incompatibilist definition is true, then nothing determines our free choices, not even our own desires . For if our desires were determining our choices then if we were to rewind the tape of time and, so to speak, reset everything— including our desires —the same way, then given those same desires we would choose the same way every time. And that would mean our choice was not free, according to the incompatbilist. It is imperative to remember that incompatibilism says that if an action is not free if it is determined ( including if it is determined by our own desires ). But now the question is: if my desires are not causing my decision, what is? When I make a decision, where does that decision come from, if not from my desires and beliefs? Presumably it cannot come from nothing ( ex nihilo nihil fit ). The problem is that if the incompatibilist rejects that anything is causing my decisions, then how can my decisions be anything but arbitrary?

Presumably an arbitrary decision—a decision not driven by any reason at all—is not an exercise of my freedom. Freedom seems to require that we are exercising some kind of control over my actions and decisions. If my action or decision is arbitrary that means that no reason or explanation of the action/decision can be given. Here’s the arbitrariness objection cast as a reductio ad absurdum argument:

• A free choice is one that isn’t determined by anything, including our desires. [incompatibilist definition of freedom]
• If our own desires are not determining our choices, then those choices are arbitrary.
• If a choice is arbitrary then it is not something over which we have control
• If a choice isn’t something over which we have control, then it isn’t a free choice
• Therefore, a free choice is not a free choice (from 1-4)

A reductio ad absurdum argument is one that starts with a certain assumption and then derives a contradiction from that assumption, thereby showing that assumption must be false. In this case, the incompatibilist’s definition of a free choice leads to the contradiction that something that is a free choice isn’t a free choice.

What has gone wrong here? The compatibilist will claim that what has gone wrong is incompatibilist’s idea that a free action must be one that isn’t caused/determined by anything. The compatibilist claims that free actions can still be determined, as long as what is determining them is our own internal reasons, over which we have some control, rather than external things over which we have no control. Free choices, according to the compatibilist, are just choices that are caused by our own best reasons . The fact that, given the exact same choices, I couldn’t have chosen otherwise doesn’t undermine what freedom is (as the incompatibilist claims) but defines what it is. Consider an example. Suppose that my goal is to spend the shortest amount of time on my commute home from work so that I can be on time for a dinner date. Also suppose, for simplicity, that there are only three possible routes that I can take: route 1 is the shortest, whereas route 2 is longer but scenic and 3 is more direct but has potentially more traffic, especially during rush hour. I am leaving early from work today so that I can make my dinner date but before I leave, I check the traffic and learn that there has been a wreck on route 1. Thus, I must choose between routes 2 and 3. I reason that since I am leaving earlier, route 3 will be the quickest since there won’t be much traffic while I’m on my early commute home. So I take route 3 and arrive home in a timely manner: mission accomplished. The compatibilist would say that this is a paradigm case of a free action (or a series of free actions). The decisions I made about how to get home were drive both by my desire to get home quickly and also by the information I was operating with. Assuming that that information was good and I reasoned well with it and was thereby able to accomplish my goal (that is, get home in a timely manner), then my action is free. My action is free not because my choices were undetermined, but rather because my choices were determined (caused) by my own best reasons—that is, by my desires and informed beliefs. The incompatibilist, in contrast, would say that an action is free only if I could have chosen otherwise, given all the same conditions again. But think of what that would mean in the case above! Why on earth would I choose routes 1 or 2 in the above scenario, given that my most pressing goal is to be able to get to my dinner date on time? Why would anyone knowingly choose to do something that thwarts their primary goals? It doesn’t seem that, given the set of beliefs and desires that I actually had at the time, I could have chosen otherwise in that situation. Of course, if you change the information I had (my beliefs) or you change what I wanted to accomplish (my desires), then of course I could have acted otherwise than I did. If I didn’t have anything pressing to do when I left work and wanted a scenic and leisurely drive home in my new convertible, then I probably would have taken route 2! But that isn’t what the incompatibilist requires for free will. As we’ve seen, they require the much stronger condition that one’s action be such that it could have been different even if they faced exactly the same condition over again. But in this scenario that would be an irrational thing to do. Of course, if one’s goal were to be irrational and to thwart one’s own desires, I suppose they could do that. But that would still seem to be acting in accordance with one’s desires.

Many times free will is treated as an all or nothing thing, either humans have it or they don’t. This seems to be exactly how the libertarian and hard determinist see the matter. And that makes sense given that they are both incompatibilists and view free will and determinism like oil and water—they don’t mix. But it is interesting to note that it is common for us to talk about decisions, action, or even whole lives (or periods of a life) as being more or less free . Consider the Goethe quotation at the beginning of this chapter: “none are more enslaved than those who falsely believe they are free.” Here Goethe is conceiving of freedom as coming in degrees and claiming that those who think they are free but aren’t as less free than those who aren’t free and know it. But this way of speaking implies that free will and determinism are actually on a continuum rather than a black and white either or. The compatibilist can build this fact about our ordinary ways of speaking about freedom into an argument for their position. Call this the argument from ordinary language . The argument from ordinary language is that only compatibilism is able to accommodate our common way of speaking about freedom coming in degrees—that is, as actions or decisions being more or less free. The libertarian can’t account for this since the libertarian sees freedom as an all or nothing matter: if you couldn’t have done otherwise then your action was not truly free; if you could have done otherwise, then it was. In contrast, the compatibilist is able to explain the difference between more/less free action on the continuum. For the compatibilist, the freest actions are those in which one reasons well with the best information, thus acting for one’s own best reasons, thus furthering one’s interests. The least free actions are those in which one lacks information and reason poorly, thus not acting for one’s own best reasons, thus not furthering one’s interests. Since reasoning well, being informed, and being reflective are all things that come in degrees (since one can possess these traits to a greater or lesser extent) and since these attribute define what free will is for the compatibilist, it follows that free will comes in degrees. And that means that the compatibilist is able to make sense or a very common way that we talk about freedom (as coming in degrees) and thus make sense of ourselves, whereas the libertarian isn’t.

There’s one further advantage that compatibilists can claim over libertarians. Libertarians defend the claim that there are at least some cases where one exercises one’s free will and that this entails that determinism is false. However, this leaves totally open the extent of human free will. Even if it were true that there are at least some cases where humans exercise free will, there might not be very many instances and/or those decisions in which we exercise free will might be fairly trivial (for example, moving one’s finger to the left or right). But if it were to turn out that free will was relatively rare, then even if the libertarian were correct that there are at least some instances where we exercise free will, it would be cold comfort to those who believe in free will. Imagine: if there were only a handful of cases in your life where your decision was an exercise of your free will, then it doesn’t seem like you have lived a life which was very free. In other words, in such a case, for all practical purposes, determinism would be true.

Thus, it seems like the question of how widespread free will is is an important one. However, the libertarian seems unable to answer it for reasons that we’ve already seen. Answering the question requires knowing whether or not one could have acted otherwise than one in fact did. But in order to know this, we’d have to know how to answer a strange counterfactual—whether I could have acted differently given all the same conditions. As noted earlier (“the epistemic objection”), this raises a tough epistemological question for the libertarian: how could he ever know how to answer this question? And so how could he ever know whether a particular action was free or not? In contrast, the compatibilist can easily answer the question of how widespread free will is: how “free” one’s life is depends on the extent to which one’s actions are driven by their own best reasons. And this, in turn, depends on factors such as how well-informed, reflective, and reasonable a person is. This might not always be easy to determine, but it seems more tractable than trying to figure out the truth conditions of the libertarian’s counterfactual.

In short, it seems that compatibilism has significant advantages over both libertarianism and hard determinism. As compared to the libertarian, compatibilism gives a better answer to how free will can come in degrees as well as how widespread free will is. It also doesn’t face the arbitrariness objection or the epistemic objection. As compared to the hard determinist, the compatibilist is able to give a more satisfying answer to the moral responsibility issue. Unlike the hard determinist, who sees all action as equally determined (and so not under our control), the compatibilist thinks there is an important distinction within the class of human actions: those that are under our control versus those that aren’t. As we’ve seen above, the compatibilist doesn’t see this distinction as black and white, but, rather, as existing on a continuum. However, a vague boundary is still a boundary. That is, for the compatibilist there are still paradigm cases in which a person has acted freely and thus should be held morally responsible for that action (for example, the person who embezzles money from a charity and then covers it up) and clear cases in which a person hasn’t acted freely (for example, the person who was told to do something by their boss but didn’t know that it was actually something illegal). The compatibilist’s point is that this distinction between free and unfree actions matters, both morally and legally, and that we would be unwise to simply jettison this distinction, as the hard determinist does. We do need some distinction within the class of human actions between those for which we hold people responsible and those for which we don’t. The compatibilist’s claim is that they are able to do with while the hard determinist isn’t. And they’re able to do it without inheriting any of the problems of the libertarian position.

Study questions

• True or false: Compatibilists and libertarians agree on what free will is (on the concept of free will).
• True or false: Hard determinists and libertarians agree that an action is free only when I could have chosen otherwise than I in fact chose.
• True or false: the libertarian gives a transcendental argument for why we must have free will.
• True or false: both compatibilists and hard determinists believe that all human actions are determined.
• True or false: compatibilists see free will as an all or nothing matter: either an action is free or it isn’t; there’s no middle ground.
• True or false: compatibilists think that in the case of a truly free action, I could have chosen otherwise than I in fact did choose.
• True or false: One objection to libertarianism is that on that view it is difficult to know when a particular action was free.
• True or false: determinism is a fundamental assumption of the natural sciences (physics, chemistry, biology, and so on).
• True or false: the best that support the libertarian’s position are cases of very simple or arbitrary actions, such as choosing to move my finger to the left or to the right.
• True or false: libertarians thinks that as long as my choices are caused by my desires, I have chosen freely.

For deeper thought

• Consider the Shopenhauer quotation at the beginning of the chapter. Which of the three views do you think this supports and why?
• Consider the movie The Truman Show . How would the libertarian and compatibilist disagree regarding whether or not Truman has free will?
• Consider the Tolstoy quote at the beginning of the chapter. Which of the three views does this support and why?
• Consider a child being raised by white supremacist parents who grows up to have white supremacist views and to act on those views. As a child, does this individual have free will? As an adult, do they have free will? Defend your answer with reference to one of the three views.
• Consider the eccentric neuroscientist example (above). How might a compatibilist try to show that this isn’t really an objection to her view? That is, how might the compatibilist show that this is not a case in which the individual’s action is the result of a well-informed, reflective choice?
• Actually, the phrase was originally a Latin phrase, not an English one because at the time in Medieval Europe philosophers wrote in Latin. ↵
• On the other hand, if these nonphysical decisions are supposed to have physical effects in the world (such as causing our behaviors) then although there is no problem with the agent’s decision itself being uncaused, there would still be a problem with how that decision can be translated into the physical world without violating the law of conservation of energy. ↵
• One well-known and influential attempt to reconcile moral responsibility with determinism is P.F. Strawson’s “Freedom and Resentment” (1962). ↵
• The term “epistemic” just denotes something relating to knowledge. It comes from the Greek work episteme, which means knowledge or belief. ↵

Introduction to Philosophy Copyright © by Matthew Van Cleave is licensed under a Creative Commons Attribution 4.0 International License , except where otherwise noted.

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Is Free Will an Illusion? Scientists, Philosophers Forced to Differ

Are you really in control, or is your every decision predetermined? Who's at the steering wheel: you, your genes, your upbringing, fate, karma, God?

A hot topic for several thousand years, the question of whether free will exists may never be settled to everyone's satisfaction. But in a series of new articles for the  Chronicles of Higher Education , six academics from diverse fields offer fresh perspectives from the standpoints of modern neuroscience and philosophy. Ultimately, they voted 4-2 in favor of the position that free will is merely an illusion.

The four scientists on the panel denied the existence of free will, arguing that human behavior is governed by the brain, which is itself controlled by each person's genetic blueprint built upon by his or her life experiences. Meanwhile, the two philosophers cast the dissenting votes, arguing that free will is perfectly compatible with the discoveries of neuroscience.

Jerry Coyne, an evolutionary biologist at the University of Chicago, defined free will as the possibility that, after making a decision, you could have chosen otherwise. But a "decision," Coyne argues, is merely a series of electrical and chemical impulses between  molecules in the brain  — molecules whose configuration is predetermined by genes and environment. Though each decision is the outcome of an immensely complicated series of chemical reactions, those reactions are governed by the laws of physics and could not possibly turn out differently. "Like the output of a programmed computer, only one choice is ever physically possible: the one you made," Coyne wrote.

The three other scientists concurred with Coyne's viewpoint. As Owen Jones, a professor of law and biological sciences at Vanderbilt University, put it in his essay: "Will is as free as lunch. (If you doubt, just try willing yourself out of love, lust, anger, or jealousy)."

Though everyone must be held accountable for his or her actions, neuroscience and the nonexistence of free will should be factored into some criminal cases, the scholars argued. [ Math Formula May Explain Why Serial Killers Kill ]

A counterargument came from Hilary Bok, a philosopher at the Johns Hopkins University, who said scientists misunderstand the question of free will when they argue that decisions are governed by the activity of brain cells. Free will, in her opinion, is being capable of stepping back from one's existing motivations and habits and making a reasoned decision among various alternatives. "The claim that a person chose her action does not conflict with the claim that some neural processes or states caused it; it simply redescribes it," she wrote.

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Alfred Mele, another philosopher at Florida State University, also believes the concept of free will is compatible with the findings of neuroscience. He cited a 2008 study in which volunteers were asked to push either of two buttons. According to the study, brain activity up to 10 seconds before the decision was consciously reached revealed which button the volunteer was more likely to press.

Though the study is widely viewed as evidence against free will, Mele pointed out that the study participants' brain activity accurately predicted their eventual decision only 60 percent of the time. In his view, this suggests people can consciously choose to override their brains' predispositions.

Therefore, he wrote, "I do not recommend betting the farm on the nonexistence of free will."

Follow Natalie Wolchover on Twitter @ nattyover . Follow Life's Little Mysteries on Twitter @ llmysteries , then join us on  Facebook .

Natalie Wolchover was a staff writer for Live Science from 2010 to 2012 and is currently a senior physics writer and editor for Quanta Magazine. She holds a bachelor's degree in physics from Tufts University and has studied physics at the University of California, Berkeley. Along with the staff of Quanta, Wolchover won the 2022 Pulitzer Prize for explanatory writing for her work on the building of the James Webb Space Telescope. Her work has also appeared in the The Best American Science and Nature Writing and The Best Writing on Mathematics, Nature, The New Yorker and Popular Science. She was the 2016 winner of the  Evert Clark/Seth Payne Award, an annual prize for young science journalists, as well as the winner of the 2017 Science Communication Award for the American Institute of Physics. 

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A Famous Argument Against Free Will Has Been Debunked

For decades, a landmark brain study fed speculation about whether we control our own actions. It seems to have made a classic mistake.

The death of free will began with thousands of finger taps. In 1964, two German scientists monitored the electrical activity of a dozen people’s brains. Each day for several months, volunteers came into the scientists’ lab at the University of Freiburg to get wires fixed to their scalp from a showerhead-like contraption overhead. The participants sat in a chair, tucked neatly in a metal tollbooth, with only one task: to flex a finger on their right hand at whatever irregular intervals pleased them, over and over, up to 500 times a visit.

The purpose of this experiment was to search for signals in the participants’ brains that preceded each finger tap. At the time, researchers knew how to measure brain activity that occurred in response to events out in the world—when a person hears a song, for instance, or looks at a photograph—but no one had figured out how to isolate the signs of someone’s brain actually initiating an action.

The experiment’s results came in squiggly, dotted lines, a representation of changing brain waves. In the milliseconds leading up to the finger taps, the lines showed an almost undetectably faint uptick: a wave that rose for about a second, like a drumroll of firing neurons, then ended in an abrupt crash. This flurry of neuronal activity, which the scientists called the Bereitschaftspotential , or readiness potential, was like a gift of infinitesimal time travel. For the first time, they could see the brain readying itself to create a voluntary movement.

This momentous discovery was the beginning of a lot of trouble in neuroscience. Twenty years later, the American physiologist Benjamin Libet used the Bereitschaftspotential to make the case not only that the brain shows signs of a decision before a person acts, but that, incredibly, the brain’s wheels start turning before the person even consciously intends to do something. Suddenly, people’s choices—even a basic finger tap—appeared to be determined by something outside of their own perceived volition.

As a philosophical question, whether humans have control over their own actions had been fought over for centuries before Libet walked into a lab. But Libet introduced a genuine neurological argument against free will. His finding set off a new surge of debate in science and philosophy circles. And over time, the implications have been spun into cultural lore.

Today, the notion that our brains make choices before we are even aware of them will now pop up in cocktail-party conversation or in a review of Black Mirror . It’s covered by mainstream journalism outlets, including This American Life , Radiolab , and this magazine . Libet’s work is frequently brought up by popular intellectuals such as Sam Harris and Yuval Noah Harari to argue that science has proved humans are not the authors of their actions.

It would be quite an achievement for a brain signal 100 times smaller than major brain waves to solve the problem of free will. But the story of the Bereitschaftspotential has one more twist: It might be something else entirely.

The Bereitschaftspotential was never meant to get entangled in free-will debates. If anything, it was pursued to show that the brain has a will of sorts. The two German scientists who discovered it, a young neurologist named Hans Helmut Kornhuber and his doctoral student Lüder Deecke, had grown frustrated with their era’s scientific approach to the brain as a passive machine that merely produces thoughts and actions in response to the outside world. Over lunch in 1964, the pair decided that they would figure out how the brain works to spontaneously generate an action. “Kornhuber and I believed in free will,” says Deecke, who is now 81 and lives in Vienna.

To pull off their experiment, the duo had to come up with tricks to circumvent limited technology. They had a state-of-the-art computer to measure their participants’ brain waves, but it worked only after it detected a finger tap. So to collect data on what happened in the brain beforehand, the two researchers realized that they could record their participants’ brain activity separately on tape, then play the reels backwards into the computer. This inventive technique, dubbed “reverse-averaging,” revealed the Bereitschaftspotential .

The discovery garnered widespread attention. The Nobel laureate John Eccles and the prominent philosopher of science Karl Popper compared the study’s ingenuity to Galileo’s use of sliding balls for uncovering the laws of motion of the universe. With a handful of electrodes and a tape recorder, Kornhuber and Deecke had begun to do the same for the brain.

What the Bereitschaftspotential actually meant, however, was anyone’s guess. Its rising pattern appeared to reflect the dominoes of neural activity falling one by one on a track toward a person doing something. Scientists explained the Bereitschaftspotential as the electrophysiological sign of planning and initiating an action. Baked into that idea was the implicit assumption that the Bereitschaftspotential causes that action. The assumption was so natural, in fact, no one second-guessed it—or tested it.

Libet, a researcher at the University of California at San Francisco, questioned the Bereitschaftspotential in a different way. Why does it take half a second or so between deciding to tap a finger and actually doing it? He repeated Kornhuber and Deecke’s experiment, but asked his participants to watch a clocklike apparatus so that they could remember the moment they made a decision. The results showed that while the Bereitschaftspotential started to rise about 500 milliseconds before the participants performed an action, they reported their decision to take that action only about 150 milliseconds beforehand. “The brain evidently ‘decides’ to initiate the act” before a person is even aware that decision has taken place, Libet concluded.

To many scientists, it seemed implausible that our conscious awareness of a decision is only an illusory afterthought. Researchers questioned Libet’s experimental design, including the precision of the tools used to measure brain waves and the accuracy with which people could actually recall their decision time. But flaws were hard to pin down. And Libet, who died in 2007, had as many defenders as critics. In the decades since his experiment, study after study has replicated his finding using more modern technology such as fMRI.

But one aspect of Libet’s results sneaked by largely unchallenged: the possibility that what he was seeing was accurate, but that his conclusions were based on an unsound premise. What if the Bereitschaftspotential didn’t cause actions in the first place? A few notable studies did suggest this, but they failed to provide any clue to what the Bereitschaftspotential could be instead. To dismantle such a powerful idea, someone had to offer a real alternative.

In 2010, Aaron Schurger had an epiphany. As a researcher at the National Institute of Health and Medical Research in Paris, Schurger studied fluctuations in neuronal activity, the churning hum in the brain that emerges from the spontaneous flickering of hundreds of thousands of interconnected neurons. This ongoing electrophysiological noise rises and falls in slow tides, like the surface of the ocean—or, for that matter, like anything that results from many moving parts. “Just about every natural phenomenon that I can think of behaves this way. For example, the stock market’s financial time series or the weather,” Schurger says.

From a bird’s-eye view, all these cases of noisy data look like any other noise, devoid of pattern. But it occurred to Schurger that if someone lined them up by their peaks (thunderstorms, market records) and reverse-averaged them in the manner of Kornhuber and Deecke’s innovative approach, the results’ visual representations would look like climbing trends (intensifying weather, rising stocks). There would be no purpose behind these apparent trends—no prior plan to cause a storm or bolster the market. Really, the pattern would simply reflect how various factors had happened to coincide.

“I thought, Wait a minute ,” Schurger says. If he applied the same method to the spontaneous brain noise he studied, what shape would he get?  “I looked at my screen, and I saw something that looked like the Bereitschaftspotential .” Perhaps, Schurger realized, the Bereitschaftspotential ’s rising pattern wasn’t a mark of a brain’s brewing intention at all, but something much more circumstantial.

Two years later, Schurger and his colleagues Jacobo Sitt and Stanislas Dehaene proposed an explanation. Neuroscientists know that for people to make any type of decision, our neurons need to gather evidence for each option. The decision is reached when one group of neurons accumulates evidence past a certain threshold. Sometimes, this evidence comes from sensory information from the outside world: If you’re watching snow fall, your brain will weigh the number of falling snowflakes against the few caught in the wind, and quickly settle on the fact that the snow is moving downward.

But Libet’s experiment, Schurger pointed out, provided its subjects with no such external cues. To decide when to tap their fingers, the participants simply acted whenever the moment struck them. Those spontaneous moments, Schurger reasoned, must have coincided with the haphazard ebb and flow of the participants’ brain activity. They would have been more likely to tap their fingers when their motor system happened to be closer to a threshold for movement initiation.

This would not imply, as Libet had thought, that people’s brains “decide” to move their fingers before they know it. Hardly. Rather, it would mean that the noisy activity in people’s brains sometimes happens to tip the scale if there’s nothing else to base a choice on, saving us from endless indecision when faced with an arbitrary task. The Bereitschaftspotential would be the rising part of the brain fluctuations that tend to coincide with the decisions. This is a highly specific situation, not a general case for all, or even many, choices.

Other recent studies support the idea of the Bereitschaftspotential as a symmetry-breaking signal. In a study of monkeys tasked with choosing between two equal options, a separate team of researchers saw that a monkey’s upcoming choice correlated with its intrinsic brain activity before the monkey was even presented with options.

In a new study under review for publication in the Proceedings of the National Academy of Sciences , Schurger and two Princeton researchers repeated a version of Libet’s experiment. To avoid unintentionally cherry-picking brain noise, they included a control condition in which people didn’t move at all. An artificial-intelligence classifier allowed them to find at what point brain activity in the two conditions diverged. If Libet was right, that should have happened at 500 milliseconds before the movement. But the algorithm couldn’t tell any difference until about only 150 milliseconds before the movement, the time people reported making decisions in Libet’s original experiment.

In other words, people’s subjective experience of a decision—what Libet’s study seemed to suggest was just an illusion—appeared to match the actual moment their brains showed them making a decision.

When Schurger first proposed the neural-noise explanation, in 2012 , the paper didn’t get much outside attention, but it did create a buzz in neuroscience. Schurger received awards for overturning a long-standing idea. “It showed the Bereitschaftspotential may not be what we thought it was. That maybe it’s in some sense artifactual, related to how we analyze our data,” says Uri Maoz, a computational neuroscientist at Chapman University.

For a paradigm shift, the work met minimal resistance. Schurger appeared to have unearthed a classic scientific mistake, so subtle that no one had noticed it and no amount of replication studies could have solved it, unless they started testing for causality. Now, researchers who questioned Libet and those who supported him are both shifting away from basing their experiments on the Bereitschaftspotential . (The few people I found still holding the traditional view confessed that they had not read Schurger’s 2012 paper.)

“It’s opened my mind,” says Patrick Haggard, a neuroscientist at University College London who collaborated with Libet and reproduced the original experiments.

It’s still possible that Schurger is wrong. Researchers broadly accept that he has deflated Libet’s model of Bereitschaftspotential , but the inferential nature of brain modeling leaves the door cracked for an entirely different explanation in the future. And unfortunately for popular-science conversation, Schurger’s groundbreaking work does not solve the pesky question of free will any more than Libet’s did. If anything, Schurger has only deepened the question.

Is everything we do determined by the cause-and-effect chain of genes, environment, and the cells that make up our brain, or can we freely form intentions that influence our actions in the world? The topic is immensely complicated, and Schurger’s valiant debunking underscores the need for more precise and better-informed questions.

“Philosophers have been debating free will for millennia, and they have been making progress. But neuroscientists barged in like an elephant into a china shop and claimed to have solved it in one fell swoop,” Maoz says. In an attempt to get everyone on the same page, he is heading the first intensive research collaboration between neuroscientists and philosophers, backed by $7 million from two private foundations, the John Templeton Foundation and the Fetzer Institute. At an inaugural conference in March, attendees discussed plans for designing philosophically informed experiments, and unanimously agreed on the need to pin down the various meanings of “free will.”

In that, they join Libet himself. While he remained firm on his interpretation of his study, he thought his experiment was not enough to prove total determinism—the idea that all events are set in place by previous ones, including our own mental functions. “Given the issue is so fundamentally important to our view of who we are, a claim that our free will is illusory should be based on fairly direct evidence,” he wrote in a 2004 book. “Such evidence is not available.”

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Hume on Free Will

But to proceed in this reconciling project with regard to the question of liberty and necessity; the most contentious question of metaphysics, the most contentious science… —David Hume (EU 8.23/95)

It is widely accepted that David Hume’s contribution to the free will debate is one of the most influential statements of the “compatibilist” position, where this is understood as the view that human freedom and moral responsibility can be reconciled with (causal) determinism. Hume’s arguments on this subject are found primarily in the sections titled “Of liberty and necessity”, as first presented in A Treatise of Human Nature (2.3.1–2) and, later, in a slightly amended form, in the Enquiry concerning Human Understanding (sec. 8). Although both contributions share the same title, there are, nevertheless, some significant differences between them. This includes, for example, some substantial additions in the Enquiry discussion as it relates to problems of religion, such as predestination and divine foreknowledge. These differences should not, however, be exaggerated. Hume’s basic strategy and compatibilist commitments remain much the same in both works.

This article will be arranged around a basic contrast between two alternative interpretations of Hume’s compatibilist strategy: the “classical” and “naturalistic” interpretations. According to the classical account, Hume’s effort to articulate the conditions of moral responsibility, and the way they relate to the free will problem, should be understood primarily in terms of his views about the logic of the concepts of “liberty” and “necessity”. In contrast with this, the naturalistic approach maintains that what is essential to Hume’s account of the nature and conditions of responsible conduct is his description of the role that moral sentiment plays in this sphere. How we interpret Hume’s core arguments relating to the free will debate must be understood, on this view, with reference to these psychological claims and concerns (which also accounts for the use of the label “naturalism” in this context). On either account, the contrast between these two interpretations will be of importance, not only for our general understanding of Hume’s philosophical system, but also for any adequate assessment of the contemporary value and relevance of Hume’s views on this subject.

The first two sections of this article present and contrast the classical and naturalistic interpretations. Hume’s views on causation and necessity are highly relevant to both these interpretations. The following three sections sections consider the contemporary significance of Hume’s contribution, particularly as interpreted by the naturalistic account. The sixth and final section examines the relevance of Hume’s views on free will for matters of religion.

• 1. Liberty and Necessity – The Classical Reading

2. Free Will and Moral Sentiment – The Naturalistic Reading

3. hume’s naturalism and strawson’s “reconciling project”, 4. virtue, luck and “the morality system”, 5. moral sense and moral capacity, 6. free will and the problem of religion, references to hume’s works, secondary literature, a brief guide to further reading, other internet resources, related entries, 1. “liberty and necessity” – the classical reading.

For many years the established view of Hume has been that he is a principal and founding figure of classical compatibilism, as located in the empiricist philosophical tradition that stretches from Hobbes, through Hume, on to Mill, Russell, Schlick and Ayer. Classical compatibilists believe, with libertarians, that we need some adequate theory of what free action is, where this is understood as providing the relevant conditions of moral agency and responsibility. Compatibilists, however, reject the view that free action requires the falsity of determinism or that an action cannot be both free and causally necessitated by antecedent conditions. According to the classical compatibilist strategy, not only is freedom compatible with causal determinism, the absence of causation and necessity would make free and responsible action impossible. A free action is an action caused by the agent, whereas an unfree action is caused by some other, external cause. Whether an action is free or not depends on the type of cause, not on the absence of causation and necessity. An uncaused action would be entirely capricious and random and could not be attributed to any agent, much less interpreted as a free and responsible act. Understood this way, the classical compatibilist strategy involves an attempt to explain and describe the logic of our concepts relating to issues of freedom and determinism. It is primarily concerned with conceptual issues rather than with any empirical investigations into our human moral psychology. On the classical interpretation this is how Hume’s core arguments should be understood.

As Hume’s title “Of liberty and necessity” makes plain there are two key ideas in play are “liberty” (freedom) and “necessity” (causation and determinism). In his Abstract of the Treatise Hume emphasizes that his “reasoning puts the whole [free-will] controversy in a new light, by giving a new definition of necessity” (T Abs. 34/ 661). Despite this, the classical interpretation places heavy weight on the significance of his views on the nature of liberty as the relevant basis for explaining Hume’s position on this subject. The strategy that Hume follows, according to this reading, is much the same as that which was pursued by Hobbes. It is the distinction between two kinds of liberty that is, on this account, especially important. Hume’s views on liberty in the Treatise are not, however, entirely consistent with his later views as presented in the Enquiry .

In the Treatise Hume distinguishes between two kinds of liberty.

Few are capable of distinguishing betwixt the liberty of spontaneity , as it is call’d in the schools, and the liberty of indifference ; betwixt that which is oppos’d to violence, and that which means a negation of necessity and causes. The first is even the most common sense of the word; and as ’tis only that species of liberty, which it concerns us to preserve, our thoughts have been principally turn’d towards it, and have almost universally confounded it with the other. (T 2.3.2.1/407–8)

Liberty of spontaneity involves an agent being able to act according to her own willings and desires, unhindered by external obstacles which might constrain or restrict her conduct (e.g., the walls or bars of a prison [T 2.3.1.17/406]). This kind of liberty does not imply an absence of causation and necessity, unless we incorrectly assume that what is caused is somehow compelled or forced to occur. In the Enquiry Hume drops the distinction between two kinds of liberty and instead provides an account of what he calls “hypothetical liberty” (EU 8.23/95). A liberty of this kind involves “a power of acting or not acting, according to the determinations of the will ; that is, if we choose to remain at rest, we may; if we choose to move, we also may.” According to Hume this sort of hypothetical liberty is “universally allowed to belong to every one, who is not a prisoner and in chains” (ibid.). Although Hume is committed to the existence of both liberty of spontaneity and hypothetical liberty, they are not the same. A person may enjoy liberty of spontaneity and act according to the determinations of her own will, and still lack hypothetical liberty. If she chose otherwise her action might still be obstructed (e.g., as with a person who chooses to remain in a room but could not leave if she chose to because the door is locked).

In the Treatise Hume tends to identify liberty with indifference rather than spontaneity and even suggests “that liberty and chance are synonimous” (T 2.3.2.8/412; cf. T 2.3.1.18/407; but see also EU 8.25/96). For this reason he presents his arguments as aiming to show that liberty, so understood ( qua indifference), is, if not contradictory, “directly contrary to experience” (T 2.3.1.18/407). In placing emphasis on this negative task of refuting “the doctrine of liberty or chance ” (T 2.3.2.7/412), Hume is happy to present himself as coming down firmly on the side of “the doctrine of necessity” (T 2.3.2.3/409), which he is careful to define in a way that avoids any confusion between causation and compulsion or force (as is explained in more detail below). The account that Hume offers in the Enquiry strikes a more balanced note. In this work Hume presents his position as not so much a refutation of “the doctrine of liberty” or “free-will” (T 2.3.1.18/407; cf. T 2.1.10.5/312), but rather as a “reconciling project with regard to the question of liberty and necessity” (EU 8.23/95; although even in the Enquiry his references to liberty are not uniformly to spontaneity). Although these differences should be noted, it is important not to exaggerate them. In the Treatise Hume makes clear that liberty of spontaneity is “the most common sense of the word” and the “only… species of liberty, which it concerns us to preserve” (T 2.3.2.1/407–8). It is evident, therefore, that there is also a “reconciling project” implicit in the Treatise and that his arguments against “the doctrine of liberty” remain tightly focused on liberty of indifference.

In both the Treatise and the Enquiry Hume claims that the most original or interesting part of his contribution to free will rests with his definition or understanding of what we mean by necessity (T 2.3.1.18, 2.3.2.4/407, 409–10; see also EU 8.1–3, 8.21–25/80–81, 92–96). It is this issue, Hume claims, that has been the primary obstacle to resolving this controversy. According to Hume there are “two particulars, which we are to consider as essential to necessity, viz. the constant union and the inference of the mind; and wherever we discover these we must acknowledge a necessity” (T 2.3.1.4/400). In order to explain this, Hume begins with a description of causation and necessity as we observe it in “the operations of external bodies” (T 2.3.1.3/399) or in “the actions of matter” (T Abs. 34/ 661). Here we find “not the least traces of indifference or liberty” and we can see that “[e]very object is determin’d by an absolute fate” (T 2.3.1.3/400). What this means, Hume explains, is that we discover that there exist constant conjunctions of objects, whereby resembling objects of one kind are uniformly followed by resembling objects of another kind (e.g., Xs are uniformly followed by Ys). (See, in particular, T 1.3; T Abs. 8–9, 24–26/649–50, 655–57; and also EU 4 and 7). When we experience regularities of this sort we are able to draw relevant inferences, and we deem objects of the first kind causes and those of the second kind their effects.

The crucial point, on Hume’s account, is that we can discover no further “ ultimate connexion ” (T 1.3.6.11/91) between cause and effect beyond our experience of their regular union. There is no perceived or known power or energy in a cause such that we could draw any inference to its effect or by which the cause compels or forces its effect to occur (T 1.3.12.20, 1.3.14.4–7/139, 157–59). Nevertheless, on the basis of our experience of regularities or constant conjunctions of objects, the mind, on the appearance of the first object, naturally draws an inference to that of the other (T 1.3.14.20–22, 31/164–66, 169–70; cf. EU 7.28–29/75–77). In other words, our experience of regularities serves as the basis upon which we can draw inferences to the existence of an object on the appearance of another. All that we find of causation and necessity in bodies or matter, Hume argues, is this conjunction of like objects along with the inference of the mind from one to the other. The relevant question, therefore, is do we find similar features in the operations of human action?

Our experience, Hume maintains, proves that “our actions have a constant union with our motives, tempers, and circumstances” and that we draw relevant inferences from one to the other on this basis (T 2.3.1.4/401). Although there are some apparent irregularities in both the natural and the moral realms, this is entirely due to the influence of contrary or concealed causes of which we are ignorant (T 2.3.1.11–12/403–4; cf. EU 8.15/88).

[T]he union betwixt motives and actions has the same constancy, as that in any natural operations, so its influence on the understanding is also the same, in determining us to infer the existence of one from that of another. If this shall appear, there is no known circumstance, that enters into the connexion and production of the actions of matter, that is not to be found in all the operations of the mind; and consequently we cannot, without a manifest absurdity, attribute necessity to the one, and refuse it to the other. (T 2.3.1.14/404)

In support of this claim Hume cites various regularities that we observe in human society, where class, sex, occupation, age, and other such factors are seen to be reliably correlated with different motives and conduct (T 2.3.1.5–10/401–3). Regularities of this kind make it possible for us to draw the sorts of inferences that are needed for human social life, such as in all our reasoning concerning business, politics, war, and so on (T 2.3.1.15/405; EU 8.17–18/89–90). In the absence of necessity, so understood, we could not survive or live together.

Hume goes on to argue that not only is necessity of this kind essential to human society, it is also “essential to religion and morality” (T 2.3.2.5 410), because of its relevance to the foundations of responsibility and punishment. If the motives of rewards and punishments had no uniform and reliable influence on conduct then law and society would be impossible (ibid.; cp. EU 8.28/ 97–98; see also T 3.3.4.4/609). Beyond this, whether we consider human or divine rewards and punishments, the justice of such practices depends on the fact that the agent has produced or brought about these actions through her own will. The “doctrine of liberty or chance,” however, would remove this connection between agent and action and so no one could be properly held accountable for their conduct (T 2.3.2.6/411). It is, therefore, “only upon the principles of necessity, that a person acquires any merit or demerit from his actions, however the common opinion may incline to the contrary” (ibid.; EU 8.31/99). Read this way, Hume is mostly restating a claim found in many other compatibilist accounts, that necessity (determinism) is needed to support a generally forward-looking, utilitarian theory of moral responsibility and punishment.

Why, then is there so much resistance to “the doctrine of necessity”? The principal explanation for this resistance to “the doctrine of necessity” is found, according to Hume, in confusion about the nature of necessity as we discover it in matter . Although in ordinary life we all rely upon and reason upon the principles of necessity there may well be some reluctance to call this union and inference necessity.

But as long as the meaning is understood, I hope the word can do no harm.… I may be mistaken in asserting, that we have no idea of any other connexion in the actions of body.… But sure I am, I ascribe nothing to the actions of the mind, but what must readily be allow’d of.… I do not ascribe to the will that unintelligible necessity, which is suppos’d to lie in matter. But I ascribe to matter, that intelligible quality, call it necessity or not, which the most rigorous orthodoxy does or must allow to belong to the will. I change, therefore, nothing in the receiv’d systems, with regard to the will, but only with regard to material objects. (T 2.3.2.4/410; cp. EU 8.22/93–94)

The supposition that there is some further power or energy in matter, whereby causes somehow compel or force their effects to occur, is the fundamental source of confusion on this issue. It is this that encourages us to reject the suggestion that our actions are subject to necessity on the ground that this would imply some kind of violence or constraint – something that would be incompatible with liberty of spontaneity. When confusions of this sort are removed, all that remains is the verbal quibble about using the term “necessity” – which is not itself a substantial point of disagreement.

Hume’s suggestion that our ideas of causation and necessity should be understood in terms of constant conjunction of objects and the inference of the mind became a central thread of the classical compatibilist position. A key element of this is his diagnosis of the source of incompatibilism as rooted in a confusion between causation and compulsion. What are we to make of this aspect of the compatibilist strategy? The first thing we need to consider is how this argument stands in relation to the other compatibilist arguments already described? We may begin by noting that Hume’s strategy, as built around his “new definition of necessity” (TA, 34/661), appears to concede that a stronger metaphysical “tie” or “bond” between cause and effect would indeed “imply something of force, violence, and constraint”. From the perspective of the (core) compatibilist argument, as developed around the notion of “liberty of spontaneity” and “hypothetical liberty”, this is a basic mistake. The distinction that is crucial to the original argument is that between actions that have causes that are internal to the agent (i.e., motives and desires of some relevant kind) and those that have external causes. It is the latter that are compelled or constrained actions (such as we find in the case of the prisoner who is in chains: EU 8.23/95). This crucial distinction between actions that are brought about through the agent’s motives and desires and those that are not is not compromised by “metaphysical” (non-regularity) accounts of causation. What is relevant to whether an action was compelled or not is the nature of the cause (i.e., the object), not the nature of the causal relation . Hume’s argument relating to the advantages of his “new definition of necessity” directly challenges this – so one or other of these two claims must be abandoned.

Another crucial claim of the original strategy was that if an agent is to be (justly) held responsible for her actions then she must be causally connected to them in the right way. Hume’s “new definition of necessity” presents some awkward problems for this requirement. More specifically, it may be argued that if we remove “metaphysical” necessity of any kind from our conception of the causal relation, and all objects are “entirely loose and separate... conjoined but never connected ” (EU 7.26/73–4 – Hume’s emphasis), Hume’s own form of compatibilism is vulnerable to the same objection that he raised against the suggestion that free actions are uncaused . That is to say, a mere regular conjunction between events cannot serve to adequately connect the agent with her action. Hume’s theory of causation, therefore, threatens to saw off the compatibilist branch that he is sitting on.

Apart from these “internal” difficulties among Hume’s core arguments, it may also be questioned whether Hume’s alternative account of causation serves to allay or diffuse other (and deeper) worries that libertarians and incompatibilists may have about his proposed “reconciliation”. What libertarians seek – particularly but not exclusively in the 18th c. context – is an account of moral agency that rests with agents who possess active powers of some kind such that they have genuine open alternatives in the same (causal) conditions. Related to this, libertarians also insist on making a distinction between agents who can intervene in the natural causal order and, on the other side, beings who are simply part of the natural causal order and fully integrated within it. Real agency requires the causal series to begin with the agent, not to run through the agent. Hume’s revisionary “new definitions” of causation and necessity satisfies none of these fundamental concerns or requirements. Although Hume suggests that “a few intelligible definitions” should immediately put an end to this controversy (EU 8.2/81), he must have been well aware that he was far from providing the sort of metaphysical resources that libertarians are seeking or satisfying the demands that they place on free, responsible moral agency.

Hume also advances two other explanations for resistance to “the doctrine of necessity”. One of these concerns religion, which we discuss further below. The other concerns, what we might describe as the phenomenology of agency and the way in which it seems to discredit Hume’s necessitarian claims. Hume concedes that when we consider our actions from the agent’s perspective (i.e., the first person perspective) we have “ a false sensation or experience even of the liberty of indifference” (T 2.3.2.2/408 – Hume’s emphasis; cf. EU 8.22n18/94n). The basis of this is that when we are acting we may not experience any “determination of thought” whereby we infer the action to be performed. However, from the spectator’s (third person) perspective the situation is quite different. The spectator will “seldom feel such a looseness and indifference” and will reliably infer actions from an agent’s motives and character. For this reason, although when we act we may find it hard to accept that “we were govern’d by necessity, and that ’twas utterly impossible for us to have acted otherwise” (T 2.3.2.1/407), the spectator’s perspective shows that this is simply a “false sensation”. Put another way, the agent perspective may encourage the view that the future is “open” with respect to how we will act but this supposition is contradicted by the opposing spectator perspective, which is generally reliable. It is worth adding that this claim is consistent with Hume’s account in the Enquiry of “hypothetical liberty”. There is no contradiction between a spectator being able to reliably infer how an agent will act and the fact that how that agent will act depends on how he wills in these circumstances.

The above interpretation suggests that Hume’s primary aim in his discussion “Of liberty and necessity” is to defend an account of moral freedom understood in terms of “liberty of spontaneity”. Our tendency to confuse this form of liberty with indifference is a result of a mistaken understanding of the nature of causation and necessity. The significance of Hume’s contribution, on this interpretation, rests largely with his application of his “new definition of necessity” to this issue. All this is, in turn, generally consistent with arguments by leading representatives of classical compatibilism who came after Hume (viz. Mill, Russell, Schlick, Ayer, et al). If this is an accurate and complete account of Hume’s approach then it is liable to all the objections that have been levelled against the classical compatibilist view.

The first and most obvious of these objections is that “liberty of spontaneity” is a wholly inadequate conception of moral freedom. Kant, famously, describes this account of moral freedom as a “wretched subterfuge” and suggests that a freedom of this kind belongs to a clock that moves its hands by means of internal causes. If our will is itself determined by antecedent natural causes, then we are no more accountable for our actions than any other mechanical object whose movements are internally conditioned. Individuals who enjoy nothing more than a liberty of this nature are, the incompatibilist claims, little more than “robots” or “puppets” subject to the play of fate. This general line of criticism, targeted against any understanding of moral freedom in terms of “spontaneity”, leads directly to two further important criticisms.

The incompatibilist maintains that if our willings and choices are themselves determined by antecedent causes then we could never choose otherwise than we do. Given the antecedent causal conditions, we must always act as we do. We cannot, therefore, be held responsible for our conduct since, on this account, we have no “genuine alternatives” or “open possibilities” available to us. Incompatibilists, as already noted, do not accept that Hume’s notion of “hypothetical liberty”, as presented in the Enquiry , can deal with this objection. It is true, of course, that hypothetical liberty leaves room for the truth of conditionals that suggest that we could have acted otherwise if we had chosen to do so. However, it still remains the case, the incompatibilist argues, that the agent could not have chosen otherwise given the actual circumstances. Responsibility, they claim, requires categorical freedom to choose otherwise in the same circumstances. Hypothetical freedom alone will not suffice. One way of expressing this point in more general terms is that the incompatibilist holds that for responsibility we need more than freedom of action, we also need freedom of will – understood as a power to choose between open alternatives. Failing this, the agent has no ultimate control over her conduct.

Hume’s effort to draw a distinction between free and unfree (i.e., compelled) action itself rests on a distinction between internal and external causes. Critics of compatibilism argue that this – attractively simple – distinction is impossible to maintain. It seems obvious, for example, that there are cases in which an agent acts according to the determinations of his own will but is nevertheless clearly unfree. There are, in particular, circumstances in which an agent may be subject to, and act on, desires and wants that are themselves compulsive in nature (e.g., as with a drug addict or kleptomaniac). Desires and wants of this kind, it is claimed, limit and undermine an agent’s freedom no less than external force and violence. Although it may be true that in these circumstances the agent is acting according to his own desires or willings, it is equally clear that such an agent is neither free nor responsible for his behavior. It would appear, therefore, that we are required to acknowledge that some causes “internal” to the agent may also be regarded as compelling or constraining. This concession, however, generates serious difficulties for the classical compatibilist strategy. It is no longer evident, given this concession, which “internal” causes should be regarded as “constraining” or “compelling” and which should not. Lying behind this objection is the more fundamental concern that the spontaneity argument presupposes a wholly inadequate understanding of the nature of excusing and mitigating considerations.

Finally, on this reading, Hume is understood as defending an essentially forward-looking and utilitarian account of moral responsibility. Following thinkers like Thomas Hobbes, Hume points out that rewards and punishments serve to cause people to act in some ways and not in others, which is clearly a matter of considerable social utility (T 2.3.2.5/410; EU 8.2897–98). This sort of forward-looking, utilitarian account of responsibility has been further developed by a number of other compatibilists with whom Hume is often closely identified (e.g., Moritz Schlick and J.J.C. Smart). Forward-looking, utilitarian accounts of responsibility of this kind have been subject to telling criticism. The basic problem with any account of this kind, incompatibilists have argued, is that they are entirely blind to matters of desert and so lack the required (backward-looking) retributive element that is required in this sphere. Moreover, any theory of responsibility of this kind, critics say, is both too wide and too narrow. It is too wide because it would appear to make children and animals responsible; and it is too narrow because it implies that those who are dead and beyond the reach of the relevant forms of “treatment” are actually responsible for their actions. For all these reasons, critics argue, we should reject compatibilist theories constructed along the lines of these distinctions.

What we need to ask now is to what extent the classical interpretation serves to capture the essentials of Hume’s position on this subject? From the perspective of the alternative naturalistic reading there are two fundamental flaws in the classical reading:

First, and foremost, the classical reading fails to provide any proper account of the role of moral sentiment in Hume’s understanding of (the nature and conditions) of moral responsibility. Part of the explanation for this is that the classical interpretation treats Hume’s views on free will in isolation from other parts of his philosophical system. In particular, it fails to adequately integrate his discussion of free will with his theory of the passions (T 2.1 and 2.2). We are more vulnerable to this mistake if we rely too heavily on Hume’s discussion “Of liberty and necessity” as presented in the Enquiry .

Second, and related to the first issue, the classical reading suggests an overly simple, if not crude, account of the relationship between freedom and moral responsibility. Whereas the classical account suggests that responsibility may be analyzed directly in terms of free (or voluntary) action, the naturalistic interpretation suggests a very different picture of this relationship. It would not be correct, for example, to interpret Hume as endorsing what J.L. Mackie has called “the straight rule of responsibility”: which is that “an agent is responsible for all and only his intentional actions” (Mackie, 1977): 208; and also 221–2). This is, nevertheless, a view that the classical interpretation encourages.

In order to see where the classical interpretation goes wrong we need to begin with an examination of Hume’s arguments in support of the claim that necessity is essential to morality and that “indifference” would make morality impossible (T 2.3.2.5–7/410–2).

In order to understand the relevance of necessity for the conditions of holding a person responsible we we need to understand the workings of “the regular mechanism” of the indirect passions (DP 6.19). In his discussion of love and hatred Hume says:

One of these suppositions, viz. that the cause of love and hatred must be related to a person or thinking being, in order to produce these passions, is not only probable, but too evident to be contested. Virtue and vice, when consider’d in the abstract… excite no degree of love and hatred, esteem or contempt towards those, who have no relation to them. (T 2.2.1.7/331)

Our virtues and vices are not the only causes of love and hatred. Wealth and property, family and social relations, bodily qualities and attributes may also generate love or hate (T 2.1.2.5; 2.1.7.1–5/279, 294f; DP 2.14–33). It is, nevertheless, our virtues and vices, understood as pleasurable or painful qualities of mind, that are “the most obvious causes of these passions” (T 2.1.7.2/295; cp. 3.1.2.5/473; and also 3.3.1.3/574–5). In this way, by means of the general mechanism of the indirect passions, virtue and vice give rise to that “faint and imperceptible” form of love and hatred which constitutes the moral sentiments. This is essential to all our ascriptions of moral responsibility.

Hume makes clear that it is not actions, as such, that give rise to our moral sentiments but rather our more enduring or persisting character traits (T 2.2.3.4/348–9; and also 3.3.1.4–5/575). The crucial passage in his discussion “Of liberty and necessity” is the following:

Actions are by their very nature temporary and perishing; and where they proceed not from some cause in the characters and disposition of the person, who perform’d them, they infix not themselves upon him, and can neither redound to his honour, if good, nor infamy, if evil. The action itself may be blameable… But the person is not responsible for it; and as it proceeded from nothing in him, that is durable or constant, and leaves nothing of that nature behind it, ‘tis impossible he can, upon its account, become the object of punishment or vengeance. (T 2.3.2.6/411; cp. EU 8.29/98; see also T 3.3.3.4/575: “If any action…”)

Further below, in Book II, Hume expands on these remarks:

‘Tis evident, that when we praise any actions, we regard only the motives that produc’d them, and consider the actions as signs or indications of certain principles in the mind and temper. The external performance has no merit. We must look within to find the moral quality. This we cannot do directly; and therefore fix our attention on actions, as on external signs. But these actions are still consider’d as signs; and the ultimate object of our praise and approbation is the motive, that produc’d them. (T 3.2.1.2/477; cp. 3.2.1.8/479; EU 8.31/99)

In these two passages Hume is making two distinct but related points. First, he maintains that “action”, considered as an “external performance” without any reference to the motive or intention that produced it, is not itself of moral concern. It is, rather, the “internal” cause of the action that arouses our moral sentiments. It is these aspects of action that inform us about the mind and moral character of the agent. Second, the moral qualities of an agent that arouse our moral sentiments must be “durable or constant” – they cannot be “temporary and perishing” in nature in the way actions are. This second condition on the generation of moral sentiment is itself a particular instance of the more general observation that Hume has made earlier on in Book II that the relationship between the quality or feature that gives rise to the indirect passions (i.e., its cause) and the person who is the object of the passion must not be “casual or inconstant” (T 2.1.6.7/293). It is, nevertheless, the first point that is especially important for our present purpose of understanding why necessity is essential to morality.

In order to know anyone’s motives and character we require inference, from their actions to their motives and character (T 2.1.11.3; 3.3.1.7/317, 576). Without knowledge of anyone’s character no sentiment of approbation or blame would be aroused in us. Without inferences moving in this direction – from action to character (as opposed to from character to actions) – no one would be an object of praise or blame and, hence, no one would be regarded as morally responsible. In these circumstances, praising and blaming would be psychologically impossible. Along the same lines, external violence, like liberty of indifference, also makes it impossible to regard someone as an object of praise or blame. When an action is produced by causes external to the agent we are led away from the agent’s character. Clearly, then, actions that are either uncaused or caused by external factors cannot render an agent responsible, not because it would be unreasonable to hold the person responsible, but rather because it would be psychologically impossible to hold the person responsible, where this stance is understood in terms of the operation of the moral sentiments. It is in this way that Hume brings his observations concerning the operation of the indirect passions to bear on his claim that necessity is essential to morality and, in particular, to our attitudes and practices associated with responsibility and punishment.

In light of this alternative account, we may conclude that the nature of Hume’s compatibilist strategy is significantly misrepresented by the classical interpretation. Hume’s arguments purporting to show that necessity is essential to morality are intimately connected with his discussion of the indirect passions and the specific mechanism that generates the moral sentiments. Whereas the classical interpretation construes his arguments as conceptual or logical in nature, the naturalistic interpretation presents Hume as concerned to describe the circumstances under which people are felt to be responsible. Interpreted this way, Hume’s arguments constitute a contribution to descriptive moral psychology and, as such, they are an important part of his wider program to “introduce the experimental method of reasoning into moral subjects” (which is the subtitle of the Treatise ).

The next question to consider is whether or not the issues that divide the classical and naturalistic interpretations are of any contemporary significance or interest? The first thing to be said about this is that from a contemporary perspective, classical compatibilism seems too crude an account of both freedom and moral responsibility and very few philosophers would still press the claim that incompatibilist prejudices can be explained simply in terms of confusion about necessity arising from a conflation between causation and compulsion. In contrast with this, Hume’s concern with the role and relevance of moral sentiment for our understanding of the free will problem anticipates several key features of P.F. Strawson’s highly influential contribution to the contemporary debate. Strawson’s “Freedom and Resentment” [hereafter FR] is arguably the most important and influential paper concerning the free will problem published in the second half of the twentieth century. The most striking affinity between the approaches taken by Hume and Strawson is their shared appeal to the role of moral sentiments or reactive attitudes, which both use as a way of discrediting any supposed sceptical threat arising from the thesis of determinism.

On Strawson’s account, both classical compatibilists (whom he refers to as “optimists”) and libertarians (whom he refers to as “pessimists”, because they suppose determinism threatens moral responsibility) make a similar mistake of “over-intellectualizing the facts” by seeking to provide some sort of “external ‘rational’ justification” for moral responsibility (FR, 81). The classical compatibilist does this on the basis of a “one-eyed utilitarianism”, whereas the libertarian, seeing that something vital is missing from the classical compatibilist account, tries to plug the gap with “contra-causal freedom” – which Strawson describes as “a pitiful intellectualist trinket” (FR, 81). Against views of these kinds, Strawson argues that we should focus our attention on the importance of reactive attitudes or moral sentiments in this context. By this means he hopes to find some middle ground whereby he can “reconcile” the two opposing camps. Our reactive attitudes or moral sentiments, Strawson argues, should be understood in terms of our natural human emotional responses to the attitudes and intentions that human beings manifest towards each other. We expect and demand some degree of good will and due regard and we feel resentment or gratitude depending on whether or not this is shown to us (FR, 66–7). Granted that these emotions are part of our essential human make-up, and are naturally triggered or aroused in relevant circumstances, it is still important to recognize that these responses are in some measure under rational control and we can “modify or mollify” them in light of relevant considerations (FR, 68).

There are two kinds of consideration that Strawson distinguishes that may require us to amend or withdraw our reactive attitudes. First, there are considerations that we may describe as exemptions, where we judge that an individual is not an appropriate or suitable target of any reactive attitudes. These are cases where a person may be viewed as “psychologically abnormal” or “morally underdeveloped” (FR, 68; and also 71–2). On the other hand, even where exemptions of this sort do not apply, ordinary excusing considerations may nevertheless require us to alter or change our particular reactive attitudes as directed toward some individual (FR, 68). Considerations of this kind include cases where an agent acts accidentally, or in ignorance, or was subject to physical force of some kind. Where these considerations apply we may come to recognize that the conduct in question, properly interpreted, does not lack the degree of good will or due regard that we may demand. Even if some injury has occurred, no malice or lack of regard has been shown to us. However, the crucial point for Strawson is that while our reactive attitudes may well be modified or withdrawn in these circumstances, there is no question of us altogether abandoning or suspending our reactive attitudes (FR, 71–3). In particular, there is nothing about the thesis of determinism that implies that either exemptions or excuses, as Strawson has described them, apply or hold universally (FR, 70–1). Moreover, and more controversially, Strawson also maintains that even if determinism did provide some “theoretical” basis for drawing this sceptical conclusion, any such policy is “for us as we are, practically inconceivable” (FR, 71). In other words, according to Strawson our natural commitment to the fabric of moral sentiment insulates us from any possible global sceptical threat to the whole fabric of moral responsibility based on theoretical worries about the implications of determinism.

If we read Hume along the lines of the classical interpretation, then his position on these issues looks as if it accords very closely with the typical “optimist” strategy associated with such thinkers as Schlick. The classical interpretation, however, entirely overlooks the role of moral sentiment in Hume’s reconciling strategy. It emphasizes the relevance of the (supposed) confusion between causation and compulsion in order to explain the more fundamental confusion about the nature of liberty (i.e., why philosophers tend to confuse liberty of spontaneity with liberty of indifference). With these features of Hume’s position established, the classical interpretation points to Hume’s remarks concerning the social utility of rewards and punishments and the way in which they depend on the principles of necessity. From this perspective, Hume’s discussion of freedom and necessity clearly constitutes a paradigmatic and influential statement of the “optimist’s” position. So interpreted, Hume must be read as a thinker, like Schlick, who has “over-intellectualized the facts” on the basis of a “one-eyed-utilitarianism”; one who has ignored “that complicated web of attitudes and feelings” which Strawson seeks to draw our attention to. In this way, we are encouraged to view Hume as a prime target of Strawson’s attack on the “optimist” position.

The naturalistic interpretation, by contrast, makes it plain that any such view of Hume’s approach and general strategy is deeply mistaken. Hume, no less than Strawson, is especially concerned to draw our attention to the facts about human nature that are relevant to a proper understanding of the nature and conditions of moral responsibility. More specifically, Hume argues that we cannot properly account for moral responsibility unless we acknowledge and describe the role that moral sentiment plays in this sphere. Indeed, unlike Strawson, Hume is much more concerned with the detailed mechanism whereby our moral sentiments are aroused, and thus he is particularly concerned to explain the relevance of spontaneity, indifference, and necessity to the functioning of moral sentiment. To this extent, therefore, Hume’s naturalistic approach is more tightly woven into his account of the nature of necessity and moral freedom. In sum, when we compare Hume’s arguments with Strawson’s important and influential discussion, it becomes immediately apparent that there is considerable contemporary significance to the contrast between the classical and naturalistic interpretations of Hume’s reconciling strategy.

The overall resemblance between Hume’s and Strawson’s strategy in dealing with issues of freedom and responsibility is striking. The fundamental point that they agree about is that we cannot understand the nature and conditions of moral responsibility without reference to the crucial role that moral sentiment plays in this sphere. This naturalistic approach places Hume and Strawson in similar positions when considered in relation to the views of the pessimist and the optimist. The naturalistic approach shows that, in different ways, both sides of the traditional debate fail to properly acknowledge the facts about moral sentiment. Where Hume most noticeably differs from Strawson, however, is on the question of the “general causes” of moral sentiment. Strawson largely bypasses this problem. For Hume, this is a crucial issue that must be settled to understand why necessity is essential to responsibility and why indifference is entirely incompatible with the effective operation of the mechanism that responsibility depends on.

We have noted that the classical and naturalistic interpretations differ in how they account for the relationship between freedom and responsibility. According to the classical interpretation responsibility may be analysed directly in terms of free action, where this is understood simply in terms of an agent acting according to her own will or desires. While classical compatibilists reject the incompatibilist suggestion that free and responsible action requires indeterminism or any special form of “moral causation” they are, nevertheless, both agreed that a person can be held responsible if and only if she acts freely. On the naturalistic interpretation, however, Hume rejects this general doctrine, which we may call “voluntarism”.

Hume maintains that it is a matter of “the utmost importance” for moral philosophy that action must be indicative of durable qualities of mind if a person is to be held accountable for it (T 3.3.1.4/575). This claim is part of Hume’s more general claim that our indirect passions (including our moral sentiments) are aroused and sustained only when the pleasurable or painful qualities concerned (e.g. the virtues and vices) stand in a durable or constant relation with the person who is their object (T 2.1.6.7/292–3; DP 2.11). In the case of actions, which are “temporary and perishing”, no such lasting relation is involved unless action is suitably tied to character traits of some kind. Two important issues arise out of this that need to be carefully distinguished.

(1) Does Hume hold that all aspects of virtue for which a person is subject to moral evaluation (i.e., approval and disapproval) must be voluntarily expressed? That is to say, are virtues and vices to be assessed entirely on the basis of an agent’s deliberate choices and intentional actions? (2) Granted that virtues and vices are to be understood in terms of a person’s pleasant or painful qualities of mind, to what extent are these traits of character voluntarily acquired (i.e., acquired through the agent’s own will and choices)?

Hume’s answer to both questions is clear. He denies that voluntary or intentional action is the sole basis on which we may assess a person’s virtues and vices. Furthermore he also maintains that moral character is, for the most part, involuntarily acquired. The second claim does not, of course, commit him to the first. Nor does the first commit him to the second, since a person could voluntarily acquire traits that, once acquired, may be involuntarily expressed or manifest. Plainly the combination of claims that Hume embraces on this issue commits him to a position that radically deflates the significance and importance of voluntariness in relation to virtue – certainly in comparison with some familiar alternative accounts (e.g. as in Aristotle).

Let us consider, first, the relevance of voluntariness to the expression of character. As we have already noted, Hume does take the view that actions serve as the principal way in which we learn about a person’s character (T 3.3.1.5/575). Action is produced by the causal influence of our desires and willings. The interpretation and evaluation of action must, therefore, take note of the particular intention with which an action was undertaken. Failing this, we are liable to attribute character traits to the agent that he does not possess (and consequently unjustly praise or blame him). Although intention and action do have a significant and important role to play in the assessment of moral character, Hume also maintains that there are other channels through which character may be expressed. More specifically, a virtuous or vicious character can be distinguished by reference to a person’s “wishes and sentiments,” as well as by the nature of the person’s will (T 3.3.1.5/575). Feelings, desires and sentiments manifest themselves in a wide variety of ways – not just through willing and acting. A person’s “countenance and conversation” (T 2.1.11.3/317), deportment or “carriage” (EU 8.15/88), gestures (EU 8.9/85), or simply her look and expression, may all serve as signs of character and qualities of mind that may be found to be pleasant or painful. Although we may enjoy some limited degree of control over our desires and passions, as well as how they are expressed, for the most part our emotional states and attitudes arise in us involuntarily and may even be manifest or expressed against our will.

We may now turn to the further question concerning Hume’s understanding of the way in which virtues and vices are acquired and, in particular, to what extent they are shaped and conditioned by our own choices. It is Hume’s view that, by and large, our character is conditioned and determined by factors independent of our will. In the sections “Of liberty and necessity” (T 2.3.1–2; EU 8) he argues that not only do we observe how certain characters will act in specific circumstances, we also observe how circumstances condition character. Among the factors that determine character, he claims, are bodily condition, age, sex, occupation and social station, climate, religion, government, and education (T 2.3.1.5–10/401–03; EU 8.7–15/83–8; see esp. EU 8.11/85–6: “Are the manners ...”). These various causal influences account for “the diversity of characters, prejudices, and opinions” (EU 8.10/85). Any accurate moral philosophy, it is argued, must acknowledge and take note of the forces that “mould the human mind from its infancy” and which account for “the gradual change in our sentiments and inclinations” through time (EU 8.11/86). The general force of these observations is to establish that “the fabric and constitution of our mind no more depends on our choice, than that of our body” (ESY 168; see also T 3.3.4.3/608; ESY 140, 160, 579).

Critics of Hume’s position on this subject will argue that if a person has little or no control over the factors that shape her character then virtue and vice really would be, in these circumstances, matters of mere good or bad fortune and no more a basis for moral concern than bodily beauty or ugliness. (See Reid 1969: 261: “What was, by an ancient author, said of Cato…”.) If people are responsible for the character that their actions and feelings express, then they must have acquired that character voluntarily. Hume’s reply to this line of criticism is that we can perfectly well distinguish virtue and vice without making any reference to the way that character is acquired. Our moral sentiments are reactions or responses to the moral qualities and character traits that people manifest in their behavior and conduct, and thus need not be withdrawn simply because people do not choose or voluntarily acquire these moral characteristics. Hume does recognize, of course, that we do have some limited ability to amend and alter our character. In particular, Hume acknowledges that we can cultivate and improve our moral character, in some measure, through self-criticism and self-understanding. Nevertheless, the points he emphasizes are that all such efforts are limited in their scope and effect (ESY 169) and that, beyond this, “a man must be, before-hand, tolerably virtuous” for such efforts of “reformation” to be undertaken in the first place.

Hume’s views about the relationship between virtue and voluntariness do much to explain one of the most controversial aspects of his theory of virtue: his view that the natural abilities should be incorporated into the virtues and vices (T 3.3.4; EM App 4). With respect to this issue he makes two key points. The first is that natural abilities (i.e., intelligence, imagination, memory, wit, etc.) and moral virtues more narrowly understood are “equally mental qualities” (T 3.3.4.1/606). Second, both of them “equally produce pleasure” and thus have “an equal tendency to produce the love and esteem of mankind” (T 3.3.4.1/606–07). In common life, people “naturally praise or blame whatever pleases or displeases them and thus regard penetration as much a virtue as justice” (T 3.3.4.4/609). (See, e.g., Hume’s sardonic observation at EM App. 4.5/315: “It is hard to tell...”) Beyond all this, as already noted, any distinction between the natural abilities and moral virtues cannot be based on the consideration that the natural abilities are for the most part involuntarily acquired, since this also holds true for the moral virtues more narrowly conceived. It is, nevertheless, Hume’s view that the voluntary/involuntary distinction helps to explain “why moralists have invented” the distinction between natural abilities and moral virtues. Unlike moral qualities, natural abilities “are almost invariable by any art or industry” (T 3.3.4.4/609). In contrast with this, moral qualities, “or at least, the actions that proceed from them, may be chang’d by the motives of rewards and punishments, praise and blame” (T 3.3.4.4/609). In this way, according to Hume, the significance of the voluntary/involuntary distinction is largely limited to our concern with the regulation of conduct in society. To confine our understanding of virtue and vice to these frontiers is, however, to distort and misrepresent its very nature and foundation in human life and experience. (For more on Hume’s views on virtue in relation to his position on free will see Russell, 2013.)

These observations regarding Hume and the doctrine of voluntarism are of considerable relevance to the contemporary ethical debate as it concerns what Bernard Williams has described as “the morality system” (Williams, 1985: Chp. 10). Although Williams’ (hostile) account of the morality system is multifaceted and defies easy summary, its core features are clear enough. The concept that Williams identifies as fundamental to the morality system is its special notion of obligation. Flowing from this special concept of obligation are the related concepts of right and wrong, blame and voluntariness. When agents voluntarily violate their obligations they do wrong and are liable to blame and some measure of retribution. To this extent the morality system, so conceived, involves what Williams calls “the blame system”, which focuses on particular acts (Williams, 1985: 194). According to Williams there is pressure within the blame system “to require a voluntariness that will be total and will cut through character and psychological or social determinism, and allocate blame and responsibility on the ultimately fair basis of the agent’s own contribution, no more and no less” (Williams, 1985: 194).

One reason why the morality system places great weight on the importance of voluntariness is that it aspires to show that morality – and moral responsibility in particular – somehow “transcends luck” (Williams, 1985: 195). This is required to ensure that blame is allocated in a way that is “ultimately fair”. Despite the obvious challenges this requirement poses, compatibilists have typically tried to satisfy these aspiration of the morality system by way of offering a variety of argument to show that compatibilist commitments do not render us vulnerable to the play of fate or luck in our moral lives (e.g. Dennett, 1984). Hume, however, makes little effort to satisfy these aspirations. (A point that Williams notes in Williams, 1995: 20n12.) In the final analysis, Hume claims, just as every body or material object “is determin’d by an absolute fate to a certain degree and direction of its motion, and can no more depart from that precise line, in which it moves, than it can convert itself into an angel, or spirit, or any superior substance” (T 2.3.1.3/400), so too our conduct and character is similarly subject to an “absolute fate” as understood in terms of the inescapable “bonds of necessity” (T 2.3.2.2/408). In these fundamental respects, therefore, Hume takes the view, along with Williams, that morality does not elude either fate or luck. In this Hume, perhaps, shares more with the ancient Greeks than he does with those moderns who embrace the aspirations of the morality system (see, e.g., Williams, 1993).

From a critical perspective, it may be argued that there remains a significant gap in Hume’s scheme as we have so far described it. Even if we discard the aspirations of the morality system, any credible naturalistic theory of moral responsibility needs to be able to provide some account of the sorts of moral capacity involved in exempting conditions, whereby we deem some individuals and not others as appropriate targets of moral sentiments or “reactive attitudes”. As it stands, what Hume has to say on this subject is plainly inadequate. According to Hume, it is an ultimate inexplicable fact about our moral sentiments (qua calm forms of the indirect passions of love and hate) that they are always directed at people, either ourselves or others. This account leaves us unable say why some people are not appropriate objects of moral sentiments (e.g. children, the insane, and so on). There are, however, several available proposals for dealing with this gap. Perhaps the most influential proposal is to adopt some general theory of reason-responsiveness or rational self-control. According to accounts of this kind, responsible agents need to have control over their actions, where this involves performing “those actions intentionally, while possessing the relevant sorts of normative competence: the general ability to grasp moral requirements and to govern one’s conduct by light of them” (Wallace, 1994: 86). While proposals of this general kind help to plug a large gap in Hume’s theory, they also suggest a particular understanding of moral responsibility that is not entirely in keeping with Hume’s own account.

There are two points of divergence that are especially significant with respect to to issue. First, rational self-control may be explained, as it is on Wallace’s account, in terms of specifically Kantian conceptions of practical reason and moral agency (Wallace, 1994: 12–17). Even if commitments of this kind are avoided, theories of this kind are still too narrowly based on moral capacity as it relates solely to actions and intentions. On Hume’s account, moral capacity must be related to wider patterns and dispositions of feeling, desire and character. The scope of moral evaluation should not be reduced or limited to concern with (fleeting and momentary) acts of will modelled after legal paradigms. Moral capacity must be exercised and manifest in a larger and more diverse set of propensities and abilities that make up moral character, including the operation of moral sentiment itself.

Second, and related to the previous point, although Hume does not provide any substantial or robust theory of moral capacity, it is possible to find, within what he provides, material that suggests a less “rationalistic” understanding of moral capacity. It may be argued, for example, that in Hume’s system there is an intimate and important relationship between moral sense and virtue. Our moral sense should be understood in terms of our general capacity to feel and direct moral sentiments at both ourselves and at others. Hume points out that children acquire the artificial virtues, involving the conventions of justice, by way not only of learning their advantages but also learning to feel the relevant moral sentiments when these conventions are violated (T 3.2.3.26/500–01). The mechanism of the moral sentiments both cultivates and maintains the artificial virtues. Hume has less to say about the role of moral sentiment in relation to the natural virtues but similar observations would seem to apply. As children grow up and mature they become increasingly aware that their qualities of character affect both others and themselves and that these will inevitably give rise to moral sentiments in the people they will deal with. This entire process of becoming aware of the moral sentiments of others, and “surveying ourselves as we appear to others” (T 3.3.1.8, 3.3.1.26, 3.3.1.30, 3.3.6.6/576–7, 589, 591, 620; EM 9.10, App. 4.3/276, 314) surely serves to develop the natural as well as the artificial virtues. Along these lines, Hume maintains that this disposition to “survey ourselves” and seek our own “peace and satisfaction” is the surest guardian of every virtue (EM 9.10/276). Any person who entirely lacks this disposition will be shameless and will inevitably lack all the virtues that depend on moral reflection for their development and stability.

If this conjecture regarding the intimate or internal relationship between virtue and moral sense is correct, then it does much to explain and account for the range of exemptions that are required in this area. Hume’s understanding of the operation of moral sentiment is not simply a matter of enjoying pleasant and painful feelings of a peculiar kind (T 3.1.2.4/472). On the contrary, the moral evaluation of character involves the activity of both reason and sentiment. The sort of intellectual activities required include not only learning from experience the specific pleasant and painful tendencies of certain kinds of character and conduct, as well as the ability to distinguish accurately among them, but also the ability to evaluate character and conduct from “some steady and general point of view” (T 3.3..15/581–2; EM 5.41–2/227–8). Clearly, then, insofar as the cultivation and stability of virtue depends on moral sense, it also requires the intellectual qualities and capacities involved in the exercise of moral sense. (One way of understanding this is to say that moral sense and moral reflection serve as the counterparts to practical wisdom or phronesis in Aristotle’s moral theory. See Russell, 2006.) Given this, an animal, an infant, or an insane person will lack the ability to perform the intellectual tasks involved in the production of moral sentiment. We cannot, therefore, expect virtues that are dependent on these abilities and intellectual activities to be manifest in individuals who lack them, or when they are damaged or underdeveloped.

Interpreting Hume in these terms not only serves to fill what looks like a large gap in his naturalistic program, it also avoids distorting his own wider ethical commitments by imposing a narrower, rationalistic conception of moral capacity into his naturalistic framework. Beyond this, interpreting moral capacity in these more sentimentalist terms is both philosophically and psychologically more satisfying and plausible. On an account of this kind, there exists a close and essential relationship between being responsible, where this is understood in terms of being an appropriate target of moral sentiments or reactive attitudes, and being able to hold oneself and others responsible, where this is understood as the ability to experience and entertain moral sentiments. It is a merit of Hume’s system, so interpreted, that it avoids “over-intellectualizing” not only what is involved in holding a person responsible, but also what is involved in being a responsible agent.

In the Treatise , as was noted earlier, Hume argues that one of the reasons “why the doctrine of liberty [of indifference] has generally been better receiv’d in the world, than its antagonist [the doctrine of necessity], proceeds from religion, which has been very unnecessarily interested in this question” (T 2.3.2.3/409). He goes on to argue “that the doctrine of necessity, according to my explication of it, is not only innocent, but even advantageous to religion and morality”. When Hume came to present his views afresh in the Enquiry (Sec. 8), he was less circumspect about his hostile intentions with regard to “religion”. In the parallel passage (EU 8.26/96–97), he again objects to any effort to refute a hypothesis “by a pretence to its dangerous consequences to religion and morality”. He goes on to say that his account of the doctrines of liberty and necessity “are not only consistent with morality, but are absolutely essential to its support” (EU 8.26/97). By this means, he makes it clear that he is not claiming that his position is “consistent” with religion. In the final passages of the Enquiry discussion of liberty and necessity (EU 8.32–6/99–103) – passages which do not appear in the original Treatise discussion – Hume makes it plain exactly how his necessitarian principles have “dangerous consequences for religion”.

Hume considers the following objection:

It may be said, for instance, that, if voluntary actions be subjected to the same laws of necessity with the operations of matter, there is a continued chain of necessary causes, pre-ordained and pre-determined, reaching from the original cause of all to every single volition of every human creature… . The ultimate Author of all our volitions is the Creator of the world, who first bestowed motion on this immense machine, and placed all beings in that particular position, whence every subsequent event, by an inevitable necessity, must result. Human action, therefore, either can have no moral turpitude at all, as proceeding from so good a cause; or if they have any turpitude, they must involve our Creator in the same guilt, while he is acknowledged to be their ultimate cause and author. (EU 8.32/99–100)

In other words, the doctrine of necessity produces an awkward dilemma for the theological position: Either the distinction between (moral) good and evil collapses, because everything is produced by a perfect being who intends “nothing but what is altogether good and laudable” (EU 8.33/101), or we must “retract the attribute of perfection, which we ascribe to the Deity” on the ground that he is the ultimate author of moral evil in the world.

Hume treats the first horn of this dilemma at greatest length. He draws on his naturalistic principles to show that the conclusion reached (i.e., that no human actions are evil or criminal in nature) is absurd. There are, he claims, both physical and moral evils in this world that the human mind finds naturally painful, and this affects our sentiments accordingly. Whether we are the victim of gout or of robbery, we naturally feel the pain of such evils (EU 8.34/101–2). No “remote speculations” or “philosophical theories” concerning the good or perfection of the whole universe will alter these natural reactions and responses to the particular ills and evils we encounter. Hence, even if we were to grant that this is indeed the best of all possible worlds – and Hume clearly takes the view that we have no reason to suppose that it is (D 113–4; EU 11.15–22/137–42) – this would do nothing to undermine the reality of the distinction we draw between good and evil (i.e., as experienced on the basis of “the natural sentiments of the human mind”: EU 8.35/103).

What, then, of the alternative view, that God is “the ultimate author of guilt and moral turpitude in all his creatures”? Hume offers two rather different accounts of this alternative – although he does not distinguish them properly. He begins by noting that if some human actions “have any turpitude, they must involve our Creator in the same guilt, while he is acknowledged to be their ultimate cause and author” (EU 8.32/100). This passage suggests that God is also blameworthy for criminal actions in this world, since he is their “ultimate author”. At this point, however, there is no suggestion that the particular human agents who commit these crimes (as preordained by God) are not accountable for them. In the passage that follows this is the position taken.

For as a man, who fired a mine, is answerable for all the consequences whether the train he employed be long or short; so wherever a continued chain of necessary causes is fixed, that Being, either finite or infinite, who produces the first, is likewise the author of all the rest, and must both bear the blame and acquire the praise which belong to them. (EU 8.32/100)

Hume goes on to argue that this rule of morality has even “greater force” when applied to God, since he is neither ignorant nor impotent and must, therefore, have knowingly produced those criminal actions which are manifest in the world. Granted that such actions are indeed criminal, it follows, says Hume, “that the Deity, not man, is accountable for them” (EU 8.32/100; cf. EU 8.33/101).

It is evident that Hume is arguing two points. First, if God is the creator of the world and preordained and predetermined everything that happens in it, then the (obvious) existence of moral evil is attributable to him, and thus “we must retract the attribute of perfection” which we ascribe to him. Second, if God is indeed the ultimate author of moral evil, then no individual human being is accountable for the criminal actions he performs. The second claim does not follow from the first. Moreover, it is clearly inconsistent with Hume’s general position on this subject. As has been noted, in this same context, Hume has also argued that no speculative philosophical theory can alter the natural workings of our moral sentiments. The supposition that God is the “ultimate author” of all that takes place in the world will not, on this view of things, change our natural disposition to praise or blame our fellow human beings. Whatever the ultimate causes of a person’s character and conduct, it will (inevitably) arouse a sentiment of praise or blame in other humans who contemplate it. This remains the case even if we suppose that God also deserves blame for the “moral turpitude” we find in the world. In general, then, Hume’s first formulation of the second alternative (i.e., that God must share the blame for those crimes that occur in the world) is more consistent with his naturalistic principles.

What is crucial to Hume’s polemical purpose in these passages is not the thesis that if God is the author of crimes then his human creations are not accountable for them. Rather, the point Hume is concerned to make (since he does not, in fact, doubt the inescapability of our moral accountability to our fellow human beings) is that the religious hypothesis leads to the “absurd consequence” that God is the ultimate author of sin in this world and that he is, accordingly, liable to some appropriate measure of blame. Hume, in other words, takes the (deeply impious) step of showing that if God exists, and is the creator of the universe, then he is no more free of sin than human beings are. According to Hume, we must judge God as we judge human beings, on the basis of his effects in the world, and we must then adjust our sentiments accordingly. Indeed, there is no other natural or reasonable basis on which to found our sentiments toward God. In certain respects, therefore, we can make better sense of how we (humans) can hold God accountable than we can make sense of how God is supposed to hold humans accountable (i.e., since we have no knowledge of his sentiments , or even if he has any; cf. D 58,114,128–9; ESY 594; but see also LET I/51). It is, of course, Hume’s considered view that it is an egregious error of speculative theology and philosophy to suppose that the universe has been created by a being that bears some (close) resemblance to humankind. The question of the origin of the universe is one that Hume plainly regards as beyond the scope of human reason (see, e.g., EU 1.11–2;11.15–23;11.26–7;12.2634/11–13, 137–42, 144–47, 165; D 36–8,88–9,107). Nevertheless, Hume’s point is plain: On the basis of the (limited) evidence that is available to us, we must suppose that if there is a God, who is creator of this world and who orders all that takes place in it, then this being is indeed accountable for all the (unnecessary and avoidable; D 107) evil that we discover in it.

Although it is evident that Hume’s discussion of free will in the first Enquiry is part of his wider critique of the Christian religion, it is nevertheless widely held that Hume’s earlier discussion “Of liberty and necessity” in the Treatise carries none of this irreligious content or significance. This view is itself encouraged by a more general understanding of the relationship between the Treatise and the first Enquiry which maintains that the Treatise lacks any significant irreligious content (because Hume “castrated” his work and removed most passages of this kind, perhaps including the passages at EU 8.32–6). On this view of things, the elements of Hume’s discussion that are common to both Treatise 2.3.1–2 and Enquiry 8 are themselves without any particular religious or irreligious significance. To show why this view is seriously mistaken would, however, take us wide of our present concerns. (For a more detailed account of Hume’s fundamental irreligious intentions throughout the Treatise see Russell, 2008 and also Russell, 2016.)

Suffice it to note, for our present purposes, that throughout his writings, Hume’s philosophical interests and concerns were very largely dominated and directed by his fundamental irreligious aims and objectives. A basic theme in Hume’s philosophy, so considered, is his effort to demystify moral and social life and release it from the metaphysical trappings of “superstition”. The core thesis of Hume’s Treatise – indeed, of his overall (irreligious or “atheistic”) philosophical outlook – is that moral and social life neither rests upon nor requires the dogmas of Christian metaphysics. Hume’s naturalistic framework for understanding moral and social life excludes not only the metaphysics of libertarianism (e.g., modes of “moral” causation by immaterial agents) but also all further theologically inspired metaphysics that generally accompanies it (i.e., God, the immortal soul, a future state, and so on). The metaphysics of religion, Hume suggests, serves only to confuse and obscure our understanding of these matters and to hide their true foundation in human nature. Hume’s views on the subject of free will and moral responsibility, as presented in the sections “Of liberty and necessity” and elsewhere in his writings, are the very pivot on which this fundamental thesis turns.

In the entry above, we follow the convention given in the Nortons’ Treatise and Beauchamp’s Enquiries : we cite Book. Part. Section. Paragraph; followed by references to the Selby-Bigge/Nidditch editions. Thus T 1.2.3.4/34: will indicate Treatise Bk.1, Pt.2, Sec.3, Para.4/ Selby-Bigge pg.34. References to Abstract [TA] are to the two editions of the Treatise mentioned above (paragraph/page). In the case of the Enquiries we cite Section and Paragraph; followed by page reference to the Selby-Bigge edition. Thus EU 12.1/149 refers to Enquiry Concerning Human Understanding , Sect.12, Para. 1 / Selby-Bigge pg. 149.

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The above citations may be used as the basis for further reading on this subject in the following way. Influential statements of the classical interpretation of Hume’s intentions can be found in Flew (1962), Penelhum (1975) and Stroud (1977). Prominent statements of 20 th century classical compatibilism that are generally taken to follow in Hume’s tracks include Schlick (1939), Ayer (1954) and Smart (1961). Davidson (1963) provides an important statement of the causal theory of action based on broadly Humean principles. A complete statement of the naturalistic interpretation is provided in Russell (1995), esp. Part I. For a critical response to this study see Penelhum (1998; 2000a), and also the earlier exchange between Russell (1983, 1985) and Flew (1984). The contributions by Botterill (2002) and Pitson (2016) follow up on some of the issues that are at stake here. For an account of Hume’s views on punishment – a topic that is closely connected with the problem of free will – see Russell (1990) and Russell (1995 – Chp. 10). For a general account of the 18 th century debate that Hume was involved in see Harris (2005) and Russell (2008), Chap. 16. See also O’Higgins introduction [in Collins (1717)] for further background. The works by Hobbes, Locke, Clarke and Collins, as cited above, are essential reading for an understanding of the general free will debate that Hume was involved in. Smith (1759) is a valuable point of contrast in relation to Hume’s views, insofar as Smith develops a naturalistic theory of responsibility based on moral sentiment (which Strawson follows up on). However, Smith does not discuss the free will issue directly (which is itself a point of some significance). In contrast with this, Reid (1788) is perhaps Hume’s most effective and distinguished contemporary critic on this subject and his contribution remains of considerable interest and value. With respect to Hume’s views on free will as they relate to his more general irreligious intentions see Russell (2008 – esp. Chp. 16). Similar material is covered in Russell (2016). Garrett (1997) provides a lucid overview and careful analysis of Hume’s views on liberty and necessity, which includes discussion of the theological side of Hume’s arguments and concerns. Helpful introductions discussing recent developments in compatibilist thinking, which are of obvious relevance for an assessment of the contemporary value of Hume’s views on this subject, can be found in McKenna (2004) and Kane (2005). Among the various points of contrast not discussed in this article, Frankfurt (1971) is an influential and important paper that aims to advance the classical compatibilist strategy beyond the bounds of accounts of freedom of action. However, as noted in the main text of this article, the work of P.F. Strawson (1962, 1985) is of particular importance in respect of the contemporary significance and relevance of Hume’s naturalistic strategy. Finally, for discussions of Hume’s compatibilism as it relates to his theory of causation see, for example, Russell (1988), Russell (1995), esp. Chaps.1–3, Beebee & Mele (2002), Harris (2005), Chap. 3, Millican (2010), and Berofsky (2012).

How to cite this entry . Preview the PDF version of this entry at the Friends of the SEP Society . Look up topics and thinkers related to this entry at the Internet Philosophy Ontology Project (InPhO). Enhanced bibliography for this entry at PhilPapers , with links to its database.

• Hume Texts Online [Peter Millican]. .
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• David Hume , entry by James Fieser, in the Internet Encyclopedia of Philosophy .
• Compatibilism: Can free will and determinism co-exist? , John Perry, in the Stanford News Service .

Clarke, Samuel | compatibilism | determinism: causal | free will | Hume, David | Hume, David: moral philosophy | Hume, David: on religion | incompatibilism: (nondeterministic) theories of free will | incompatibilism: arguments for | luck: moral | moral responsibility | punishment, legal | Reid, Thomas

Acknowledgments

The editors would like to thank Sally Ferguson for noticing and reporting a number of typographical errors in this entry.

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Free will and neuroscience: from explaining freedom away to new ways of operationalizing and measuring it.

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Commentary: Free Will and Neuroscience: From Explaining Freedom Away to New Ways of Operationalizing and Measuring It

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• Neuroethics, Centro Universitario Internazionale, Arezzo, Italy

The concept of free will is hard to define, but crucial to both individual and social life. For centuries people have wondered how freedom is possible in a world ruled by physical determinism; however, reflections on free will have been confined to philosophy until half a century ago, when the topic was also addressed by neuroscience. The first relevant, and now well-known, strand of research on the brain correlates of free will was that pioneered by Libet et al. (1983) , which focused on the allegedly unconscious intentions taking place in decisions regarded as free and voluntary. Libet’s interpretation of the so-called readiness potential (RP) seems to favor a sort of deflation of freedom ( Soon et al., 2008 ). However, recent studies seem to point to a different interpretation of the RP, namely that the apparent build-up of the brain activity preceding subjectively spontaneous voluntary movements (SVM) may reflect the ebb and flow of the background neuronal noise, which is triggered by many factors ( Schurger et al., 2016 ). This interpretation seems to bridge the gap between the neuroscientific perspective on free will and the intuitive, commonsensical view of it ( Roskies, 2010b ), but many problems remain to be solved and other theoretical paths can be hypothesized. The article therefore, proposes to start from an operationalizable concept of free will ( Lavazza and Inglese, 2015 ) to find a connection between higher order descriptions (useful for practical life) and neural bases. This new way to conceptualize free will should be linked to the idea of “capacity”: that is, the availability of a repertoire of general skills that can be manifested and used without moment by moment conscious control. The capacity index, which is also able to take into account the differences of time scales in decisions, includes reasons-responsiveness and is related to internal control, understood as the agent’s ownership of the mechanisms that trigger the relevant behavior. Cognitive abilities, needed for one to have capacity, might be firstly operationalized as a set of neuropsychological tests, which can be used to operationalize and measure specific executive functions, as they are strongly linked to the concept of control. Subsequently, a free will index would allow for the search of the underlying neural correlates of the capacity exhibited by people and the limits in capacity exhibited by each individual.

Introduction—Free Will as a Problem (Not Only) for Science

The concept of free will is hard to define, but crucial to both individual and social life ( Kane, 2005 ). Free will can be the reason why someone is not sent to jail during a trial upon appealing to insanity: the subject was not “free” when they committed the crime, not because someone was pointing a gun to their head, but because a psychiatric illness prevented them from controlling their actions. According to a long-standing philosophical tradition, if someone was not “free” when they did something, they cannot be held responsible for their deed ( Glannon, 2015 ). And the freedom in question is both “social” freedom (linked to constraints imposed by our peers or by external factors), and the one indicated by the term free will .

Free will can be defined by three conditions ( Walter, 2001 ). The first one is the “ability to do otherwise.” This is an intuitive concept: to be free, one has to have at least two alternatives or courses of action between which to choose. If one has an involuntary spasm of the mouth, for example, one is not in the position to choose whether to twist one’s mouth or not. The second condition is the “control over one’s choices.” The person who acts must be the same who decides what to do. To be granted free will, one must be the author of one’s choices, without the interference of people and of mechanisms outside of one’s reach. This is what we call agency, that is, being and feeling like the “owner” of one’s decisions and actions. The third condition is the “responsiveness to reasons”: a decision can’t be free if it is the effect of a random choice, but it must be rationally motivated. If I roll a dice to decide whom to marry, my choice cannot be said to be free, even though I will freely choose to say “I do”. On the contrary, if I choose to marry a specific person for their ideas and my deep love for them, then my decision will be free.

Thus defined, free will is a kind of freedom that we are willing to attribute to all human beings as a default condition. Of course there are exceptions: people suffering from mental illness and people under psychotropic substances ( Levy, 2013 ). Nevertheless, the attribution of free will as a general trend does not imply that all decisions are always taken in full freedom, as outlined by the three conditions illustrated above: “We often act on impulse, against our interests, without being fully aware of what we are doing. But this does not imply that we are not potentially able to act freely. Ethics and law have incorporated these notions, adopting the belief that usually people are free to act or not to act in a certain way and that, as a result, they are responsible for what they do, with the exceptions mentioned above” ( Lavazza and Inglese, 2015 ).

It is commonly experienced that the conditions of “ability to do otherwise”, “control” and “responsiveness to reasons” are very rarely at work all at once. Moreover, they would require further discussion, because there is wide disagreement on those conditions as regards their definition and scope ( Kane, 2016 ). But for the purposes of this article, this introductory treatment should suffice. In fact, the description of free will that I have sketched here is the one that dominated the theoretical discourse on, and practical applications of, the evaluation of human actions. From a philosophical point of view, however, starting with Plato, the main problem has been that of the actual existence of freedom, beyond the appearances and the insights that guide our daily life. The main challenge to free will has been determinism: the view that everything that happens (human decisions and actions included) is the consequence of sufficient conditions for its occurrence ( Berofsky, 2011 ). More specifically, “It is the argument that all mental phenomena and actions are also, directly or indirectly, causally produced—according to the laws of nature (such as those of physics and neurobiology)—by previous events that lie beyond the control of the agents” ( Lavazza and Inglese, 2015 ). Determinism was first a philosophical position; then, the birth of Galilean science—founded on the existence of immutable laws that are empirically verifiable—has increased its strength, giving rise to the concept of incompatibilism, namely the idea that free will and natural determinism cannot coexist. Only one of them can be true.

Throughout the centuries, despite its conceptual progress, philosophy hasn’t been able to solve this dilemma. As a result, today there are different irreconcilable positions about human free will: determinism is not absolute and free will exists; free will does not exist for a number of reasons, first of all (but not only) determinism; free will can exist even if determinism is true ( Kane, 2011 ). A little more than 30 years ago, neuroscience and empirical psychology came into play. Although biological processes cannot be considered strictly deterministic on the observable level of brain functioning (nerve signal transmission), new methods of investigation of the brain, more and more precise, have established that the cerebral base is a necessary condition of behavior and even of mental phenomena. On the basis of these acquisitions, neuroscience has begun to provide experimental contributions to the debate on free will.

In order to better understand the neural bases of free will, provided that there are any, in this article I’ll review and integrate findings from studies in different fields (philosophy, cognitive neuroscience, experimental and clinical psychology, neuropsychology). Unlike previous reviews on free will and neuroscience ( Haggard, 2008 , 2009 ; Passingham et al., 2010 ; Roskies, 2010a ; Brass et al., 2013 ), I have no claim of being exhaustive. My goal is to highlight a paradigm shift in the analysis and interpretation of the brain determinants preceding and/or causing free or voluntary action ( Haggard, 2008 takes voluntary decision to be non-stimulus driven, as much as possible). Firstly, following Libet’s experiments, a widespread interpretation of the so-called readiness potential (RP) went in the direction of a deflation of freedom ( Crick, 1994 ; Greene and Cohen, 2004 ; Cashmore, 2010 ; Harris, 2012 ). Indeed, the discovery of the role of the RP has been taken as evidence of the fact that free will is an illusion, since it seems that specific brain areas activate before we are aware of the onset of the movement. However, recent studies seem to point to a different interpretation of the RP, namely that the apparent build-up of the brain activity preceding subjectively spontaneous voluntary movements (SVM) may reflect the ebb and flow of the background neuronal noise, which is triggered by many factors ( Schurger et al., 2016 ). This interpretation seems to bridge, at least partially, the gap between the neuroscientific perspective on free will and the intuitive, commonsensical view of it ( Roskies, 2010b ), but many problems remain to be solved and other theoretical paths can be hypothesized. After analyzing the change of paradigm of these perspectives, I’ll propose to start from an operationalizable concept of free will ( Lavazza and Inglese, 2015 ) to find a connection between higher order descriptions (useful for practical life) and neural bases.

Neuroscience: Purporting to Explain Free Will

The discovery of the readiness potential.

As a preliminary consideration, it is important to underline that the idea of using an experiment (or a series of experiments) to establish whether the human being can be said to have free will implies accepting a direct link between a measurement of brain functioning and a pre-existing theoretical construct. This direct connection, as it is known, presents several problems and as we shall see, needs conceptual refinement to avoid simplifications and unfounded claims. What one can see and measure in brain activity may in fact only grasp a part of the idea of free will that we would like to test. This was one of the main criticisms to the experiments conducted so far ( Mele, 2009 ; Nachev and Hacker, 2014 ). What is measured at the level of brain functioning in the laboratory does not match the concept of free will we refer to, for example, to determine whether someone who engaged in violent behavior could have done otherwise in that specific circumstance.

The first relevant, and now well-known, strand of research on the brain correlates of free will was that pioneered by Libet et al. (1983) , which focused on the allegedly unconscious intentions affecting decisions regarded as free and voluntary. It should be noted that the concepts involved—“conscious intentions”, “voluntary decisions”, “free decisions”—have no clear and shared definition ( Nachev and Hacker, 2014 ), and the experiments themselves have been differently interpreted and often criticized ( Lavazza and De Caro, 2010 ). In any case, Libet’s experiments and their variants have been repeated several times until very recently, confirming their findings with a sufficient degree of reliability.

Libet based his work on Kornhuber and Deecke’s (1965) discovery of the bereitschaftpotential : the RP, a slow build-up of a scalp electrical potential (of a few microvolts), mainly measured through electroencephalography (EEG), that precedes the onset of subjectively SVM ( Kornhuber and Deecke, 1965 ). According to its discoverers, the RP is “the electro-physiological sign of planning, preparation, and initiation of volitional acts” ( Kornhuber and Deecke, 1990 ). “The neurobiologist John Eccles speculated that the subject must become conscious of the intention to act before the onset of this RP. Libet had the idea that he should test Eccles’s prediction” ( Doyle, 2011 ).

In his experiments, Libet invited the participants to move their right wrist and to report the precise moment when they had the impression that they decided to do so, thanks to a big clock they had in front of them ( Libet et al., 1983 ). In this way, it was possible to estimate the time of awareness with respect to the beginning of the movement, measured using an electromyogram (which records the muscle contraction). During the execution of the task, brain electrical activity was recorded through electrodes placed on the participants’ scalps. The attention was focused on a specific negative brain potential, namely the RP, originated from the supplementary motor area (SMA): a brain area involved in motor preparation, which is visible in the EEG signal as a wave that starts before any voluntary movement, while being absent or reduced before involuntary and automatic movements.

When one compares the subjective “time” of decision and what appeared at a cerebral level, the result appears as a striking blow to the traditional view of free will ( Libet, 1985 , 2004 ). In the experiment, the RP culminating in the execution of the movement starts in the prefrontal motor areas long before the time when the subject seems to have made the decision: participants became aware of their intention to take action about 350 ms after the onset of such potential. The volitional process is detected to start unconsciously 550 ms before the action is made in the case of non-preplanned acts and 1000 ms before in the case of preplanned acts. Thus these findings seem to show that our simple actions (and therefore, potentially, also more complex ones) are triggered by unconscious neural activity and that the awareness of those actions only occurs at a later time, when we think we are willing to act.

In the first phase of its intervention in the debate on free will, therefore, neuroscience seemed to argue for a deflation of freedom. Neuroscientists identified a specific aspect of the notion of freedom (the conscious control of the start of the action) and researched it: the experimental results seemed to indicate that there is no such conscious control, hence the conclusion that free will does not exist. However, it is important to highlight that this interpretation strongly depends on the idea that free choices or actions are fully internally generated, in the sense that they are not externally determined—where “external” means outside the subject’s conscience and the subject is something akin to the self. As we shall see, though, this distinction seems to be neither relevant nor truly informative when considering if and how choices are free.

In fact, Libet left the subject some time to veto: about 150 ms. This is the time needed for the muscles to flex in response to the command of the primary motor cortex (M2) through the spinal motor nerve cells. In the last 50 ms the action is realized with its external manifestations (bending the wrist) without any more possible intervention by the prefrontal brain areas (see “The Veto Power” Section). Libet thought there was a role for conscious will precisely in this situation: conscious will can let the action go to completion or it can block it with the explicit veto of the movement implemented by the prefrontal areas ( Doyle, 2011 ). But the intentional inhibition of an action (a decision itself) is preceded by neural activity as well ( Filevich et al., 2012 , 2013 ). So it cannot be a completely different decision from that to take a positive decision to act.

In their experiments, Haggard and Eimer (1999) used Libet’s method, but asked the participants to perform a different task. They had to move at will either the right index finger or the left in a series of repeated trials. The authors have compared the RP and the lateralized readiness potential (LRP) in trials in which awareness appeared in shorter or longer time, that is, considering the latency of awareness compared to the RP. In their words, “the RP tended to occur later on trials with early awareness of movement initiation than on trials with late awareness, ruling out the RP as a cause of our awareness of movement initiation. However, the LRP occurred significantly earlier on trials with early awareness than on trials with late awareness, suggesting that the processes underlying the LRP may cause our awareness of movement initiation” ( Haggard and Eimer, 1999 ). From this, one can deduce that the awareness of the intention to move one finger or the other comes after the decision was “taken by the brain”, as reflected in the LRP.

Sirigu et al. (2004) and Desmurget et al. (2009) have shown that, repeating Libet’s experiments on patients with parietal lesions, it appears that they become aware of their decision to take action only when the action itself is being carried out. In these subjects the awareness of the decision does not even come before the beginning of the movement, as it tends to coincide with the motor action. It seems that in such cases the brain alteration has reduced, if not cancelled altogether, the interval of consciousness preceding the actual implementation of the action. The authors proposed that when a movement is planned, activity in the parietal cortex, as part of a cortical sensorimotor processing loop, generates a predictive internal model of the upcoming movement. And this model might form the neural correlate of motor awareness.

Fried et al. (2011) recorded the activity of 1019 neurons as 12 subjects performed self-initiated finger movements. They found progressive neuronal recruitment, particularly in the SMA, over 1500 ms before subjects reported making the decision to move. A population of 256 SMA neurons was sufficient to predict in single trials the impending decision to move: 700 ms before the participants became aware of the decision, the accuracy of the prevision was higher than 80%. Fried et al. (2011) were also able to predict, “with a precision of a few 100 ms, the time point of that voluntary decision to move”, and they implemented a computational model thanks to which “volition emerged when a change in the internally generated firing rate of neuronal assemblies crossed a certain threshold”.

Unreliability of the Conscious Intention

A slightly different trend of research compared to Libet’s comprises studies suggesting that the conscious intention of an action is strongly influenced by events that occur after the action itself was performed. In this sense, intentions are therefore partially reconstructed according to a process of inference, based on elements that come after the action. For instance, a study by Lau et al. (2006) has produced results that empirically support this hypothesis. The authors have used transcranic magnetic stimulation (TMS) on the pre-supplementary motor (pre-SM) area, while the subjects were performing Libet’s task. The stimulation of the pre-SM through TMS happened at different time intervals, in relation to a simple voluntary movement. When the stimulation was applied 200 ms after the movement, the judgment W was moved back in time, indicating that the perception of the intention was influenced by the neural activity of the pre-SM after the motor action was made (cf. also Lau et al., 2004 ; Lau and Passingham, 2007 ).

In another experiment, Banks and Isham (2009) have set a slightly different version of Libet’s task: participants were asked to push a button whenever they wanted, and later they had to indicate the precise moment when they had the intention to do so. When they pushed the button, subject received an auditory feedback with a delay from 5 to 60 ms, so as to give them the impression that the response happened after they pushed the button. Even though the subjects weren’t aware of the delay between the action and the auditory feedback, the intention to press the button was reported as happening later in time, according to a linear function with the delay of the auditory signal feedback. The identification of the moment in which the subject had intended to press the button—measured by judgment W—was therefore largely determined by the apparent time of the subject’s response, and not the actual answer. This result indicates that the people evaluate the time when they have had the intention to take an action based on the consequences of their action and not just on the motor action itself.

Kühn and Brass (2009) conducted an experiment combining the paradigm of the stop signal ( Logan et al., 1984 ) with an intentional action paradigm. The subjects had to react in the quickest possible way by pushing a button as soon as a stimulus (e. g., a letter) was displayed at the center of a computer screen. Sometimes, just after the presentation of the stimulus, either a stop signal or a decision signal was shown: in the first case, the subjects had to try to stop responding; in the second case they could decide whether to press the button or stop responding. In the decision trials in which subjects had provided an answer, the subjects were asked if it had actually been the result of a decision, or if it had been inhibited—that is, if they had not been able to stop before the decision signal was presented.

The results have shown that in some instances, the subjects judged as intentional responses—i.e., as the result of a decision—those answers that in reality, on the basis of reaction times, were failed inhibitions. In other words, sometimes the subjects had a subjective experience of having intentionally decided to perform an action that they had actually not decided to take. These studies have empirically supported the hypothesis that the intentions to take voluntary actions are strongly influenced by events occurring after the execution of the action. In addition, they seem to confirm that the brain motor system produces a movement as the final result of its inputs and outputs; consciousness would be “informed” of the fact that a movement is going to occur and this would produce the subjective perception that the movement was decided voluntarily ( Hallett, 2007 ).

Predicting Choices

More recently, studying the activity of the frontal and parietal cortex, other neuroscientists of the group coordinated by Soon et al. (2008 , 2013) have managed to detect the “rise” of a behavioral or abstract choice/decision (to move either the right finger or the left one; to perform a mathematical operation or another with two numbers) a few seconds before the subject becomes aware of it. An unconscious brain process has already “decided” what to do when the subject still does not know what she would choose and thinks she still has the power to decide. More precisely, Soon et al. (2008) studied “free decisions” between many behavioral options using the multivariate pattern classification analysis (MVPA) which, combined with fMRI, allows one to identify specific contents of cognitive processes. “A pattern classifier, usually adopted from machine learning, can be trained on exemplars of neural patterns acquired when participants make different decisions and can learn to distinguish between these. If the activation patterns contain information about the decisions, the trained classifier can then successfully predict decision outcomes from independent data” ( Bode et al., 2014 ).

In Soon et al.’s (2008) experiment, subjects carried out a freely paced motor-decision task (choosing to press a button with either the left or the right index finger) while their brain activity was being measured using fMRI. The subjects then had to report the moment of the decision, not by using a clock as in Libet’s experiment, but by selecting a letter in a stream that was being presented during the task. Soon et al. (2008) used fMRI signals to find local neural patterns and draw from such patterns all possible information decoded second by second thanks to the statistical techniques of pattern recognition. The brain areas that were mostly involved in the performance of the actions are the primary M2 and the SMA, while two other brain regions encoded the subject’s motor decision ahead of time and with high accuracy. Indeed, the frontopolar cortex (BA10) and a portion of the cingulate cortex can be monitored to understand what kind of choice will be made by the person before they are conscious of having taken a specific decision in the task they were given. The prediction can be made, with a relevant approximation (60% mean accuracy), up to 7 s before the conscious choice is experienced by the subject, thanks to the fMRI signals detected in the BA10 (one should take into account that the subjects are asked to think hard about the choice before making it, whereas usually simple choices do not require long subjective reflection). “The temporal ordering of information suggests a tentative causal model of information flow, where the earliest unconscious precursors of the motor decision originated in frontopolar cortex, from where they influenced the buildup of decision-related information in the precuneus and later in SMA, where it remained unconscious for up to 10 s” ( Soon et al., 2008 ).

This seems to revive the old issue of God’s foreknowledge that forced theologians to wonder if man can be considered free, if someone already knows his future choices. Indeed, the authors speak of “free” decisions determined by brain activity ahead of time by placing “free” between inverted commas, as freedom is taken to be a commonsensical hypothesis. In this regard, the authors claim: “we found that the outcome of a decision can be encoded in brain activity of prefrontal and parietal cortex up to 10 s before it enters awareness. This delay presumably reflects the operation of a network of high-level control areas that begin to prepare an upcoming decision long before it enters awareness” ( Soon et al., 2008 ).

Another interesting study is that conducted by Alexander et al. (2016) : using a new experimental design, it found that the RP also occurs in the absence of movement. It suggests that “the RP measured here is unlikely to reflect preconscious motor planning or preparation of an ensuing movement, and instead may reflect decision-related or anticipatory processes that are non-motoric in nature” ( Alexander et al., 2016 ). The experimental design used a modified version of Libet’s task. Subjects had to choose between four letters whenever they wanted, by taking note of the exact moment of their choice. Later, in half the trials, the subjects had to push a button as soon as they made the decision, whereas in the other half subjects had to do nothing to mark their choice. At the end of the task, all subjects had to report when they had made their decision. In this way, by EEG, electrooculography (EOG) and electromyography (EMG), it was possible to see the RP of the decision-making both in motor and non-motor contexts.

The authors did not find any strong differences between the two RPs, thereby affirming that there is a pure cognitive contribution to RP that does not reflect processes related to movement. They thus suggest that cognitive RP might reflect action preparation, general anticipation and spontaneous neural fluctuations. Interestingly, they exclude that the RP reflects action preparation since it is a non-motor processing. And as to anticipation they cannot exclude that RP may be specifically associated with free choice. So the RP could merely reflect the average of spontaneous fluctuations (see “Other Neuroscientific Hypotheses on Free Will” Section).

Free Will as an Illusion

All these experiments seem to indicate that free will is an illusion. Yet, these relevant experiments can be interpreted in many ways. A possible view is that, in some way, determinism can be observed directly within ourselves. This interpretation might lead to the conclusion that free will is just an illusion. In fact, if one considers as a condition of free will the fact that it should be causa sui (i.e., it should be able to consciously start new causal chains), such a condition is incompatible with determinism as it is usually defined. For it, in fact, all events are linked by casual relations in the form of natural laws, which started long before we were born and which we cannot escape.

However, determinism has generally been regarded as a metaphysical claim, not refutable by empirical findings. One could properly talk of automatism in the brain, not of determinism, based on the evidence available. (In any case, endorsing indeterminism might lead to consider our behavior as the causal product of choices that every time produce different results, as if we rolled a dice. This doesn’t seem to make us any freer than if determinism were overturned; cf. Levy, 2011 ). Most importantly, another feature of freedom seems to be a pure illusion, namely the role of consciousness. The experiments considered thus far heavily question the claim that consciousness actually causes voluntary behavior. Neural activation starts the decisional process culminating in the movement, while consciousness “comes after”, when “things are done”. Therefore, consciousness cannot trigger our voluntary decisions. But the role of consciousness in voluntary choices is part of the definition of free will (but the very definition of consciousness is a matter of debate, cf. Chalmers, 1996 ).

Empirical research in psychology also shows that our mind works and makes choices without our conscious control. As proposed by psychologist Wegner (2002 , 2003 , 2004) and Aarts et al. (2004) , we are “built” to have the impression to consciously control our actions or to have the power to freely choose, even though all that is only a cognitive illusion. Many priming experiments show that people act “mechanically” (even when their behavior might appear suited to the environment and even refined). Automatic cognitive processes, of which we aren’t always aware, originate our decisions, and they were only discovered thanks to the most advanced scientific research. Ultimately, consciousness, which should exercise control and assess the reasons for a choice, is thus allegedly causally ineffective: a mere epiphenomenon, to use the terminology of the philosophy of mind. This is what has been called Zombie Challenge , “based on an amazing wealth of findings in recent cognitive science that demonstrate the surprising ways in which our everyday behavior is controlled by automatic processes that unfold in the complete absence of consciousness” ( Vierkant et al., 2013 ).

These experiments have triggered a huge debate and led scientists, philosophers and intellectuals to claim (or insist even more, if they already denied free will) that free will doesn’t exist ( Greene and Cohen, 2004 ; Cashmore, 2010 ; Harris, 2012 ). It seemed as though neuroscience had produced empirical evidence against free will, so that the century-long debate on it could be considered solved. However, Libet’s experiments have been also criticized. Much criticism was directed to the philosophical interpretation of these studies ( Mele, 2014 ) or to their theoretical assumptions ( Nachev and Hacker, 2014 ), which are important but not relevant here. Among the forms of criticism, one has to mention the theories of action that separate the deciding from the initiating ( Gollwitzer, 1999 ; Gollwitzer and Sheeran, 2006 ). In that case, free and conscious deliberating could still have a relevant casual role, long before the actual performance of the action.

Other objections, more markedly neuroscientific, were made for instance by Trevena and Miller (2010) . They argued that the RP is not an intention to move, but only indicates that an attentional process is in place in the brain, since when subjects “attended to their intention rather than their movement, there was an enhancement of activity in the pre-SMA” ( Lau et al., 2004 ). In any case, “there was no evidence of stronger electrophysiological signs before a decision to move than before a decision not to move, so these signs clearly are not specific to movement preparation”, ( Trevena and Miller, 2010 ). Others have noted that the introspective estimates of event timing are disputable or inaccurate, and measures in general are not sufficiently exact ( Dennett, 1984a , b , 2003 ).

More than Explaining Away

Other studies using multivariate pattern analysis with EEG confirmed that the subjectively free decisions might be made in the brain in the same way as evidence-based perceptual decisions ( Bode et al., 2012a , b , 2013 ). Indeed, Bode et al. (2012b) wrote,

we directly decoded choice-predictive information from neural activity before stimulus presentation on pure noise trials on which no discriminative information was present. Choice behavior on these trials was shown to be primed by the recent choice history. Modelling of sequential effects in RT and accuracy confirmed that such choice priming biased the starting point of a diffusion process toward a decision boundary, as conceptualized in evidence accumulation models of perceptual decision making ( Bode et al., 2012b ).

In other words, the authors found that internally (and maybe stochastically) generated neural activity can bias decisions that are expected to be stimulus-responsive or (possibly) reason-responsive. In this case, as in others that I will consider below, the understanding that we begin to have of the neuronal processes in play shows us that there is a complexity of factors at work. Some of these factors seem to be genuinely random, due to the pure noise produced by the default brain activity, while other factors can be traced back to the previous history of decisions taken in similar situations or related to the present one. Therefore, there is no “mysterious” start of the action as a linear process that, from the initial command, is then executed, as in Libet’s simplified model. Rather, this outcome is the result of a multiplicity of causal elements, which are homogeneous from the viewpoint of proximal mechanisms but of different relevance from the viewpoint of interpretation in terms of intentional psychology.

Another study has shown that attempts to account for (make sense of) insufficient perceptive clues use the same neural networks as those involved in “free” decision-making ( Bode et al., 2013 ). An fMRI-based pattern classifier can be trained to differentiate between different perceptual guesses and try to predict the outcome of non-perceptual decisions, like those made by the participants in the experiments considered so far. Specific activation patterns detected in the medial posterior parietal cortex have allowed the authors to make correct predictions on the participants’ free choices based on the previously decoded perceptual guesses decoded, and the other way round.

The task was the following: the participants were given a masked stimulus and had to say what category the stimulus belonged to. They had to freely choose among many categories. Thanks to the multivariate pattern analysis it was possible to identify the model of “free decisions” to make correct predictions in the context of perceptual judgments and identify the model of the “guess decisions”, to make correct predictions in the context of “free decisions”. It thus seems that a similar neural code for both types of decision is present. In those cases one could say that guessing is similar to making a free decision, since the brain, in the absence of sufficient external cues, has to decide internally. So perceptual decisions can be predicted from specific preceding neural activity when the brain doesn’t have enough internal elements to reach the threshold of perceptive decision.

Studies and commentaries have nevertheless drawn attention to possible confounds and bias in those experiments, namely they might be affected by previous choices with a form of auto-correlation in spontaneous decisions. In particular, Lages and Jaworska (2012) “trained a linear classifier to predict “spontaneous decisions” and “hidden intentions” from responses in preceding trials and achieved comparable prediction accuracies as reported for multivariate pattern classification based on voxel activities in frontopolar cortex”. Lages et al. (2013) have stressed a possible sequential information processing between trials that can introduce a confound, and recommended that “rather postulating a 50% chance level, prediction should be tested with a permutation test and/or separate multivariate classification analyses conditional on the previous response”.

The prediction of perceptual decisions from specific preceding neural activity is linked to what is defined “evidence accumulator model for free choice” ( Bode et al., 2014 ). The explanation starts with the fact that predictive activation patterns preceding decisions become increasingly similar to the patterns detected when the decision is consciously experienced by the subject. This could mean that a slow build-up of decision-related activity occurs, as it happens in accumulation of decision-related evidence to a decision threshold ( Ratcliff, 1978 ; Ratcliff and McKoon, 2008 ). Also, as already noted, when no external feedback is available, the previous choice is used as external feedback ( Akaishi et al., 2014 ). The history of previous decisions has a systematic effect on subsequent choices, related to the activity in medial posterior parietal cortex/posterior and posterior cingulate cortex ( Bode et al., 2011 , 2013 ). And the systematic effect can go in the direction of repetition or of avoidance of repetition depending on the task ( Mochizuki and Funahashi, 2014 ).

Here is an important point that deserves study from the neuroscientific point of view but also from that of a philosophical interpretation of free will. It consists in the fact that the internally generated brain activity has to do both with the stochastic noise and with the history of the subject’s choices. On the one hand, the stochastic noise comes both from the configuration that the brain has on average as a result of evolution (adaptive significance) and from individual development, resulting from random processes and environmental influences. On the other hand, the history of the choices is derived from the same process (in part stochastic) that I have just described.

In any case, if (at least some) very short-term decisions have a genesis similar to that described here, these decisions contribute to shaping the brain activity, and then, presumably, also to influencing decisions on a longer time scale that it is not yet possible to investigate experimentally. Ultimately, this could mean that there is a confluence of causal factors at the level of microdecisions. These factors add up in a way that it is hardly possible to tackle for current science. Then also the reasons motivating an action, typical of free actions, such as “I punched the stalker because it is right to punish those who behave in this way and because I wanted to set an example for all”, encoded in neural activity, can be part of the sum of neural causes.

In fact, experimental psychology has been trying to take into account long-term influences. In the so-called marshmallow experiment, researchers focused on delayed gratification ( Mischel et al., 1972 , 1989 ). A child was given a choice between one small, immediate reward and two small rewards (i. e. a larger reward) if they were able to wait some minutes while the psychologist left the room and then came back. Children who waited longer for the their rewards tended to have better life outcomes and accomplishments. Such experiments are relevant in terms of explanations and predictions, but it seems hard to trace behavioral profiles back to specific profiles of cerebral activation, once we are aware of the complexity of causal chains in the evidence accumulation model.

As Bode et al. (2014) write, in the hypothesis of an evidence accumulator that collects sensory evidence until a decision threshold is reached,

task instructions, participants’ internal motivation, and previous choices all have a strong influence on how decision tasks are performed when external information is either unavailable (as in free decisions), or unhelpful (as in perceptual guessing). In the case of free decision tasks, fluctuating intention for one or the other option may result from active competition between neural representations of both options in decision networks (or rather although not consciously monitored by the participants, the previous choice history, embodied in dynamic states of decision networks, can become the primary determinant of behavior, simply because nothing else is available ( Bode et al., 2014 ).

However, in this way things get more complicated and at a macroscopic level of behavioral observation, this blurs but doesn’t do away with the idea of free behaviors and behaviors that could be taken as unconscious decisions, of which we become aware only when the action has been performed. What remains to be solved is the problem of the distinction between external stimuli that trigger a stimulus-response circuit, and internal self-paced intentions and decisions that trigger voluntary circuit ( Haggard, 2008 ).

Other Neuroscientific Hypotheses on Free Will

Beyond determinism and consciousness.

The concept of free will relevant to our moral and legal, personal and social practices is much more complex than that captured by the experiments considered up to now. But here what matters are not so much theoretical considerations or those derived from experimental psychology (such as the role played in decisions by implementation intentions, which then re-evaluate the active role of consciousness; Gollwitzer, 1999 ), but those that originate from the neuroscientific research itself. In what might be called a new phase of empirical investigation on free will, the problem of determinism and the role of consciousness is left in the background, and the focus goes to other factors that enter the brain mechanisms of decision-making, without asking first if those processes (necessarily the most simple, at least for now) are deterministic or stochastic. On the other side, neuroscientists are trying to confine the concept of free will to operationalizable situations, so as to measure it and be able to identify, at least as a goal, its neural correlates.

There is a line of research on non-human primates, but more recently also on humans, which studies fine decision-making at the neuronal level, bringing it back to a mechanistic process that might be the neuronal interface of our common sense descriptions. This trend has been well described by Roskies (2010a , b , 2013) , who is one of the major supporters of this approach. For example, in Shadlen and Newsome’s (2001) experiments, monkeys are trained to look at stimuli consisting of points that move randomly to the right and to the left and to “indicate” the overall direction of the points. The monkeys give this indication moving their eyes (with a saccade) to the right or to the left. What emerges is that the activity of the neurons of the lateral interparietal (LIP) area increases with the information in the sensory cells of the middle temporal (MT) area and upper middle temporal (MST) area. The discharge rates rise up to reaching a given level, at which the monkey performs the saccade and the neurons stop discharging. This is the threshold for a decision to take place. The time taken to reach the threshold level depends on the perceptual characteristics of the stimulus (the strength of the movement over time) and the discharges stop after the answer was given.

The discharges also depend on whether the monkey is asked to answer when he wishes, or rather to hold back the response until the signal is given for the saccade. If the monkey is asked to wait until the signal is given to respond, LIP neurons continue to discharge even in the absence of the visual stimulus ( Gold and Shadlen, 2007 ). According to Roskies (2010b) , this is the discharge scheme of a neuron involved in the decision-making process; the levels of discharge can be maintained in the absence of the stimulus, signifying the independence of the decision from the inputs on which it operates, and the activity continues until it reaches the critical level at which the response is generated, or until the neurons that represent the elements accumulated in favor of a different choice lead to eye movement. In addition, electrical stimulation of LIP neurons can influence the monkey’s decision, indicating that LIP cells causally contribute to the process that triggers decision and action ( Hanks et al., 2006 ). It remains, however, to be established whether this role is that of deliberation that leads to a decision or that of the decision itself.

The reaction times and the accuracy in the evaluation are very similar between monkeys and humans, with the probability of choice and the response time connected in a similar way to the difficulty of discriminating the stimulus, so that it can be assumed that also in humans these neural processes are similar. A mathematical description of the dynamics of this system allows one to talk about the race towards the critical threshold ( Gold and Shadlen, 2007 ; Wong et al., 2007 ). According to this model, the neuronal populations with specific response properties represent different “hypotheses”. The discharge rates represent the strength of the evidence in favor of those hypotheses based on evidence gathered from the environment. When the evidence for and against each hypothesis is integrated, the discharge rates reach or move away from the critical level, which represents the decision point. This is the point at which the animal “made a choice” about the overall direction of movement. The first group that reaches this threshold “wins”, leading the motor response.

Schurger et al. (2012) proposed a different interpretation of the premovement buildup of neuronal activity preceding voluntary self-initiated movements in humans as well. They used “a leaky stochastic accumulator to model the neural decision of “when” to move in a task where there is no specific temporal cue, but only a general imperative to produce a movement after an unspecified delay on the order of several seconds”. According to their model, “when the imperative to produce a movement is weak, the precise moment at which the decision threshold is crossed leading to movement is largely determined by spontaneous subthreshold fluctuations in neuronal activity. Time locking to movement onset ensures that these fluctuations appear in the average as a gradual exponential-looking increase in neuronal activity” ( Schurger et al., 2012 ).

The model proposed by Schurger et al. (2012) accounts for the behavioral and EEG data recorded from human subjects performing the task and also makes a specific prediction that was confirmed in a second electroencephalography experiment: fast responses to temporally unpredictable interruptions should be preceded by a slow negative-going voltage deflection beginning well before the interruption itself, even when the subject was not preparing to move at that particular moment. The task was to repeatedly push a button, sometimes at will, sometimes in response to a sound produced by the experimenters according to a causal sequence. The speed of response (pressing the button) when the sound is produced is related to the proximity to the peak of the background brain activity, which appears to be random, an ebb and flow that has its highest point in the threshold at which it produces the decision to push the button.

According to this explanation, “the RP does not reflect processing within a specific action domain. Our finding that movement does not significantly modulate RP amplitude supports this aspect of their claim by extending the RP to the domain of covert decisions” ( Alexander et al., 2016 ). Another consequence is the fact that the neural decision to move at a specific time happens much later compared to Libet’s hypothesis, and the RP is only a by-product of a drift diffusion process. But the RP would still be predictive in that it precedes action and conscious awareness of both motor and cognitive action. However, the RP is predictive with regards the whether and the when, if a known task is performed, but not with regards to the what of the action ( Brass and Haggard, 2008 ).

Jo et al. (2013) seems to go in the same direction with their work: they considered both the positive and the negative potential shifts in a “self-initiated movement condition” as well as in a no-movement condition. The comparison of the potential shifts in different conditions showed that the onset of the RP appeared to be unchanged. “This reveals that the apparently negative RP emerges through an unequal ratio of negative and positive potential shifts. These results suggest that ongoing negative shifts of the SCPs facilitate self-initiated movement but are not related to processes underlying preparation or decision to act” ( Jo et al., 2013 ).

Murakami et al. (2014) confirmed those findings. They used rats, who had to perform a specific task: wait for a tone (which was purposely delayed) and decide when to stop waiting for it. The rats’ neuronal activity of the secondary M2 was recorded and resulted consistent with the model of integration-to-bound decision. “A first population of M2 neurons ramped to a constant threshold at rates proportional to waiting time, strongly resembling integrator output. A second population, which they propose provide input to the integrator, fired in sequences and showed trial-to-trial rate fluctuations correlated with waiting times” ( Murakami et al., 2014 ). Also, an integration model based on the recorded neuronal activity in the considered brain areas has allowed the researchers to quantitatively foresee the inter-neuronal correlations manifested during the task performance. “Together, these results reinforce the generality of the integration-to-bound model of decision-making. These models identify the initial intention to act as the moment of threshold crossing while explaining how antecedent subthreshold neural activity can influence an action without implying a decision” ( Murakami et al., 2014 ).

Schurger et al. (2016) stress that the main new finding about the brain activity preceding SVM “is that the apparent build-up of this activity, up until about 200 ms pre-movement, may reflect the ebb and flow of background neuronal noise, rather than the outcome of a specific neural event corresponding to a “decision” to initiate movement”. The model used is the bounded-integration process, “a computational model of decision making wherein sensory evidence and internal noise (both in the form of neural activity) are integrated over time by one or more decision neurons until a fixed threshold-level firing rate us reached, at which the animal issues a motor response. In the case of spontaneous self-initiated movement there is no sensory evidence, so the process is dominated by internal noise” ( Schurger et al., 2016 ). The stochastic decision model (SDM) used by Schurger et al. (2012) allowed them to claim that bounded integration seems to explain stimulus-response decision as relying on the same neural decision mechanism used for perceptual decisions and internal self-paced intention and decision as “dominated by ongoing stochastic fluctuations in neural activity that influence the precise moment at which the decision threshold is reached” ( Schurger et al., 2016 ). And this mechanism seems to be shared with all animals including crayfish ( Kagaya and Takahata, 2010 ).

The philosophical implications could be that “when one forms an intention to act, one is significantly disposed to act but not yet fully committed. The commitment comes when one finally decides to act. The SDM reveals a remarkably similar picture on the neuronal level, with the decision to act being a threshold crossing neural event that is preceded by a neural tendency toward this event” ( Schurger et al., 2016 ).

The Veto Power

Another recent study has brought back to the center of neuroscientific research the space of autonomy that the subject seems to have compared to the idea of free will as an illusion supported by the experiments based on the alleged unconscious onset of the action. Schultze-Kraft et al. (2016) showed that people are able to cancel movements after elicitation of RP if stop signals occur earlier than 200 ms before movement onset. In the real-time experiment, “subjects played a game where they tried to press a button to earn points in a challenge with a brain–computer interface (BCI) that had been trained to detect their RPs in real time and to emit stop signals” ( Schultze-Kraft et al., 2016 ).

The subjects had to press with their foot a button on the floor after a green light flashed: they could so whenever they wanted after about 2 s. Participants earned points if they pressed the button before the red light to come back (the stop signal). The experiment was composed of three phases. In the first phase, the stop signals were lit at random and the movements of the subjects were not predicted. In the second phase, the authors used data taken from the EEG on the participants in the first phase. In this way a classifier was trained to predict (with imperfect accuracy) the movements (the When and the Whether, not the What). In this phase, the BCI could foresee the fact that the subject would press the button thanks to the detection of the RP and therefore turned on the red light to earn points against the subject if it could not stop the movement. In the third phase, the subjects were informed that the BCI could “see their preparation of the movement” and they had to try to beat the computer by moving in an unforeseeable way.

In all phases of the experiment, there was no difference between RPs. While in the first phase, in 66.5% of the cases, subjects were winning by pressing the button with the green light on, in stages two and three trials in which subjects were able to beat the computer, by not pushing the button with the red light on, decreased to 31%, and warning participants of the prediction of the BCI would not help them do any better. The authors could thus claim that “despite the stereotypical shape of the RP and its early onset at around 1000 ms before EMG activity, several aspects of our data suggest that subjects were able to cancel an upcoming movement until a point of no return was reached around 200 ms before movement onset. If the stop signal occurs later than 200 ms before EMG onset, the subject cannot avoid moving” ( Schultze-Kraft et al., 2016 ). The explanation of the minimum threshold of 200 ms could reflect the time necessary for the stop signal to light up, the subject to perceive it and cancel the movement that was already being prepared.

As to which cortical areas are involved in vetoing an already initiated movement, some studies have tried to identify them. Brass and Haggard (2007) examined the voluntary inhibition using an experimental paradigm that was based on the Libet task. The subjects were asked to press a button while watching a cursor moving along the face of a clock. Every time, after pressing the button, the subjects had to signal the precise moment when they thought they decided to press the button. In addition, the instructions specified that the participants had to inhibit the execution of the response in some tests of their choice. Comparing this voluntary inhibition condition with the condition in which the action had not been inhibited, the authors observed an activation of the dorsal fronto-medial cortex (DFM). This area is different from the brain regions involved in the stop signal tasks, in which the inhibition is controlled by external signals. Furthermore, the DFM cortex is also distinct from the brain regions controlling the activity linked to the when and what components of voluntary action. Brass and Haggard (2007) have interpreted this finding as evidence that there is a mechanism of voluntary inhibition that can be dissociated, in neuroanatomo-functional terms, from an “environmental” inhibiting mechanism, which involves the lateral prefrontal cortex.

This finding was replicated in a subsequent study of Kühn et al. (2009) , in which the subjects had to avoid dropping a ball sliding down a ramp, by pressing a button before the ball came down and broke. In some tests of their choice, they could choose to voluntarily inhibit the response. The comparison of the condition of voluntary inhibition with the condition of voluntary action still showed activation of the DFM cortex, supporting the idea that this area is involved in the inhibition of voluntary action ( Schel et al., 2014 ).

Finally, Schultze-Kraft et al. (2016) declared to be agnostic about the interpretation of their data in regards of RP. As the RP is predictive of the subsequent movement, it could be read as “the leaky integration of spontaneous fluctuations in autocorrelated neural signals”. Theoretically, the question remains about the departure of the intention to block the action while the movement is being prepared, along with the possible coexistence of two intentions suggested by the commands of the experimenters. The participants in the experiment, in fact, want to win against the computer, therefore they want to push the button, and also have the intention, partly contrasting, not to push the button when the computer turns the red light on.

A More Realistic Model

This novel perspective offered by the line of research by Schurger et al. (2012) here described works on very simple decision-making processes and could be exposed to the same criticism in this regard have been made to Libet’s research line. But Roskies (2010b) has suggested some tracks along which to develop research on more complex decision-making processes, close to those relevant to social life. First, one must introduce the value of the decision, seen as a subjective or moral feature that drives action. By manipulating the expected rewards for correct action or for a particular type of decisions, or by manipulating the probabilities of the outcomes, both the decision and the activity levels of LIP neurons are altered ( Platt and Glimcher, 1999 ; Glimcher, 2002 ; Dorris and Glimcher, 2004 ; Sugrue et al., 2004 ). In this way it is possible to change the monkey’s choice about the objective of the saccade by offering her favorite reward. Although it is not known how the figures are represented, it seems that the Lip neurons can integrate the information on the value or on the reward in the decision-making process, and that information has a causal role.

As for the reasons, and the responsiveness to them, Roskies (2010b) suggests that also the reasons, albeit discursive and propositional, may be encoded as information at the neuronal level. Simplifying, in her view one might think that in a situation where, say, there is little food and many people, different populations of neurons represent the content “I am hungry”, while others represent “others need this more than I do”, others “the weak come first” and so forth, weighing reasons in terms of activation and modulation of the response of the populations of neurons delegated to the choice and the final decision. However, such a model ( Dorris and Glimcher, 2004 ) should be considered as purely hypothetical because first we do not know what are the specific populations of neurons, we don’t yet have the instruments to identify them, and we do not know their interactions (also considering the recent failures of naturalized semantics).

Secondly—and perhaps most importantly—it is unclear how what we externally call “reasons” could be activated and weighed by the decision-maker understood as a unitary subject or self, according to the description for which we truly act based on reasons. In this case, I believe one cannot seek a simple neural interface for commonsensical concepts and notions. In fact, the idea of a deep and unitary self—the idea of a conscious subject controlling her behavior instant by instant—has been strongly challenged by evidence coming from empirical psychology and cognitive neuroscience ( Dennett, 1991 ; Metzinger, 2004 , 2009 ). Therefore, one should avoid the temptation to reproduce such a description in neural levels. But if we trace back the reasons to populations of neurons in a mechanistic model—if we trace them back to thresholds—it is not easy to figure out who makes the decisions and why. If it is true that some people seem to be more sensitive to specific reasons, other than those to which other people are sensitive, and if people can change over time the reasons by which they are usually motivated, and in certain situations the same people may not to respond to the reasons to which they are usually sensitive, one has to wonder if what prevails are processes that we would call random or that, in any case, are beyond our control.

Here the role of consciousness seems again to be relevant. If experiments à la Libet seemed to have ruled it out from a causal standpoint, the experiment by Schultze-Kraft et al. (2016) on movement vetoing seems to reassess its role in blocking the preparation process triggered in the brain. In this sense, this seems to be a more realistic line of neuroscientific investigation on free will, one that contemplates, even in broad terms, stochastic brain processes, for the most part triggered by environmental stimuli, which often are not aware of (the same as our train of thoughts arising spontaneously without us being able to orientate it from the beginning), but also by spontaneous activity of the brain ( Changeux, 2004 ; Brembs, 2011 ) that creates models of reality. “Learning mechanisms evolved to permit flexible behavior as a modification of reflexive behavioral strategies. In order to do so, not one, but multiple representations and action patterns should be generated by the brain” ( De Ridder et al., 2013 ). And this repertoire is not infinite. Indeed, “our evolutionary-evolved brain potential to generate multiple action plans is constrained by what is stored in memory and by what is present in the environment” ( De Ridder et al., 2013 ). Schurger and Uithol (2015) also argue that the “actions emerge from a causal web in the brain” and that the “proprioceptive feedback might play a counterintuitive role in the decision process”. They, thus recommend the use of dynamical systems approach for the study of the origins of voluntary action.

On these spontaneous processes we can exercise control, which can be considered automatic and unconscious when evaluated with the classical theoretical criteria of conscious control. First, there is an innate behavioral repertoire of provisions linked to survival in the environments within which we evolved. Secondly, there is a repertoire of behavioral provisions that is stratified in terms of conscious repetitions due to environmental stimuli or to internal choices (with all the limitations that this expression has in reference to the brain mechanisms analyzed so far) and then becomes automatic. The control can, however, also be explicit, with obvious limitations and cases of complete control failure. Based on this complex self-construction (which has a neural correlates), we are creatures with a higher or lower degree of free will. This free will may then be better understood and circumscribed, so as to be more objectively operationalized and also measured.

Operazionalizing, Measuring and Verifying: From the Action to the Brain

My view is that a richer conceptualization of free will—one that is able to overcome the stall of the metaphysical debate as well as the current difficulties of neuroscience ( Nachev and Hacker, 2014 ) and empirical psychology ( Nahmias, 2014 )–has to be linked to the idea of “capacity”. In fact, as claimed by Mecacci and Haselager (2015) , the kind of free will investigated by neuroscientific experiments, which is self-generated and defined according to the absence of cues, “does little justice to the common sense practice of holding people responsible for their freely willed actions that consists in asking explanations and justifications from the actor” ( Mecacci and Haselager, 2015 ).

Another important point is that there are differences in time scales between laboratory tasks (the milliseconds to seconds time range) and real life or, better, life as we measure it temporally (seconds, minutes, hours, weeks, years) regarding decisions that really concern us. Even if the underlying mechanism might be the same, the experiments described so far cannot investigate whether decisions with a longer maturation process are free and to what extent they are such. It might be possible to distinguish between proximal and distal mechanisms, but this doesn’t seem feasible lacking the tools to address decisions involving longer time scales. For this reason it might be useful to introduce other and different ways to conceptualize and operationalize (supposedly) free actions.

“By capacity, in the context of free will, we mean the availability of a repertoire of general skills that can be manifested and used without the moment by moment conscious control that is required by the second condition of free will we have previously seen” ( Lavazza and Inglese, 2015 ). The concept of capacity is related to that of internal control, understood as the agent’s “ownership” of the mechanism that triggers the relevant behavior and the reasons-responsiveness of that mechanism ( Fischer and Ravizza, 2000 ). And reasons-responsiveness must involve a coherent pattern of reasons-recognition. “More specifically, it must involve a pattern of actual and hypothetical recognition of reasons that is understandable by some appropriate external observer. And the pattern must be at least minimally grounded in reality” ( Lavazza and Inglese, 2015 ). The concept of capacity used in this sense, and combined with the idea of reasons-responsiveness, also avoids the objection of determinism that has always weighed on the debate on free will. From a philosophical point of view, the approach related to capacity may fall indeed in the strand of so-called compatibilism, which defends the fact that human freedom can exist even if determinism is true of the physical world.

Cognitive abilities might be firstly operationalized as a set of neuropsychological tests, which can be used to operationalize and measure specific executive functions, as they are strongly linked to the concept of control. Executive functions, also known as control functions, are essential to organize and plan everyday behavior—which is not the instant behavior found in Libet’s experiments. Those skills are necessary to perform the greater part of our goal-oriented actions. They allow us to modulate our behavior, control its development and change it according to the environmental stimuli (the environment being both physical and social). Also, executive functions allow us to change our behavior based on it effects, with a sophisticated feedback mechanism; finally, they are also necessary for tasks of abstraction, inventiveness and judgment. Those who, for whatever reason, have a deficit in their executive functions cannot respond to their social environment appropriately, and struggle to plan their behavior or to choose between alternatives based on their judgment or interest. Sufferers of these deficits in executive functions often fail to control their instinctive responses and to modify their regular courses of action, or are unable to concentrate or persist in the pursuit of a goal ( Barkley, 2012 ; Goldstein and Naglieri, 2014 ).

In general terms, the executive functions refer to the set of mental processes necessary for the development of cognitive-behavioral patterns adaptive in response to new and demanding environmental conditions. The domain of executive functions includes ( Lavazza and Inglese, 2015 ):

• the ability of planning and evaluation of effective strategies in relation to a specific purpose related to the skills of problem-solving and cognitive flexibility.

• inhibitory control and decision-making processes that support the selection of functional response and the modification of the response (behavior) in relation to changing environmental contingencies.

• attentional control referred to the ability to inhibit interfering stimuli and to activate the relevant information.

• working memory referring to the cognitive mechanisms that can maintain online and manipulate information necessary to perform complex cognitive tasks.

• (and it can be added with regards to free will) creativity and the ability to cope with environmental changes through novel solutions.

Those of empirical psychology are higher order concepts, which act as a bridge between free will, which is something that is not in the brain but can be observed in behavior (along with its causes), and the underlying brain processes. It has been convincingly suggested that in the construction of a hierarchy of mechanisms and explanations ( Craver, 2007 ), also to guide the exploration, one must go from inside to outside and from outside to inside. One goes from measurable skills to their brain basis, and from the tentative index of free will to the underlying (real) mechanisms.

Based on the evidence presented, I believe that a viable proposal is to construct an index related to compatible tests whose relevance can be uniformly ascertained. It would be a kind of IQ-like profile that would allow for the operationalization and quantification of a person’s cognitive skills. All the tests used (for example, Stroop Test, Wisconsin Card Sorting Test, Weigl’s Color-Form Sorting Test, Go-No Go Test) should be related to the subject’s age and education and then transformed in new standardized scores (Equivalent Scores, ES) on an ordinal scale, e. g. ranging from 0 to 4, with 0 representing scores below cut-off point and 4 representing scores equal to or better than average. Specific standardized scores exist in many countries or linguistic areas. The subjects would get for each test a raw score (or RS), given by the sum of the scores obtained in each item that makes up the test, which would then be standardized.

A synthetic index such as the one here proposed measures a certain range of cognitive and behavioral control skills that configure a certain kind of free will at the psychological-functional level. These are potential capacities measured with standardized instruments in laboratory situations, which do not consider any other factors that may restrict the freedom of a subject in specific situations, such as those that are relevant in moral scenarios and legal contexts. The same goes for moral judgment. However, an index such as the one I’m proposing here could be the first step, albeit certainly imperfect, towards more objective measures to discriminate between people who have more or less “free will” or, in other words, are more or less capable of self-control and rational choice (i.e., a reasons-responsive choice).

This hypothesis would be in line with the proposals of operationalizing free will advanced so far. According to Vohs (2010) , freedom might be conceived of as the sum of executive functions and goal-directed, future-oriented behaviors, which include rational choice, planning, intelligent thought, and self-control. Free will can be then constituted by a limited stock of energy, devoted to guiding executive functioning processes. The free will index I am proposing is also consistent with Baumeister’s contribution:

Psychologists should focus on what we do best: collecting evidence about measurable variance in behaviors and inner processes and identifying consistent patterns in them. With free will, it seems most productive for psychologists to start with the well-documented observation that some acts are freer than others. As already noted, dissonance, reactance, coping with stress, and other behaviors have been shown in the laboratory to depend on variations in freedom and choice. Hence, it is only necessary to assume that there are genuine phenomena behind those subjective and objective differences in freedom. In a nutshell, we should explain what happens differently between free and unfree actions ( Baumeister, 2008 ).

Empirical research on how human beings work has recently focused on self-control as a feature of free will. Self-control can be defined as the exertion of willpower on behavior. Self-control is thus generally regarded as the capacity to override inappropriate impulses and automatic or habitual responses and to suppress or delay immediate gratification so as to reach a long-term goal ( Gailliot and Baumeister, 2007 ). “Being in control” includes the capacity to maintain goals, to balance long- and short-term values, to consider and evaluate the consequences of a planned action, and to resist being “carried away by emotion” ( Churchland, 2006 ). Self-control can also be regarded as the ability of higher-order functions to modulate the activity of lower-level functions, where higher-order functions manifest themselves externally in complex behavior, adjusted according to the environmental needs, while lower-level functions are manifested in simple and stereotyped behaviors, not adjusted according to the demands of the environment ( Roskies, 2010a ). Everyone exhibits a different degree of self-control compared to other individuals, and for each person the degree of self-control varies over time ( Baumeister et al., 2006 ; Casey et al., 2011 ; Dang et al., 2015 ). The variability of self-control that is manifested in behavior and can be measured with the test has its base in neuronal functioning, which in turn depends on education and habits, external circumstances and the internal neuronal noise.

However, two executive functions turn out to be central:

(i) the ability to predict the future outcomes of a given action; and (ii) the ability to suppress inappropriate, i.e., not sufficiently valuable, actions. Importantly, these two executive functions operate not only during the genesis of an action, but also during the planning of an already selected action. In fact, during the temporal gap between the time when an action has been chosen and the moment when the motor output is going to be generated, the context might have changed, altering the computed value of the action and thus requiring a radical change of the planned motor strategy ( Mirabella, 2014 ).

It seems that the peculiarity of our freedom at the cognitive level is the ability to modulate or block courses of action that environmental stimuli automatically or unconsciously arouse in us—a reproposal in different form of Libet’s free won’t and Schultze-Kraft’s vetoing . These psychological-functional indicators must then lead to their cerebral bases. For instance, one can consider a situation in which one’s needs are satisfied (or not) and the consequent motivation to act based on the evaluation process of the need satisfaction.

This is an essential process and one that is continuously performed by our motor system. In fact, in most places where we live, if not all, we are surrounded by tools whose sight automatically activates motor schemas that would normally be employed to interact with those objects. These actions are prompted by the features of the objects, the so-called affordances ( Gibson, 1979 ). It has been shown that even the simple observation of pictures depicting affordable objects (such as graspable objects) activates a sub-region of the medial frontal cortex, the SMA, even when there is no requirement to actually act on those stimuli ( Grèzes and Decety, 2002 ). These stimulus-driven activations are rapid, involuntary, and unconscious ( Mirabella, 2014 ).

Environmental stimuli, in this case, can induce a subject to make specific choices through a priming process that exploits our action tendencies. Typically, individuals are able to control their behavior, but in some cases they fail to do so; for example if suffering from microlesions of the SMA, people have a tendency to invariably implement a certain type of action, even if the environment, both physical and social, does not require it ( Sumner et al., 2007 ). In fact, “the suppression of a triggered action might be seen not as an active process, but rather as an automatic consequence of the evaluative procedure” ( Mirabella, 2014 ). One could then say that those who have the ability to better monitor, control and direct their own behavior are “freerer” than those who do not have this capability. Individuals affected by disorders of the executive functions are not able to grasp and process environmental stimuli to direct their behavior. For example, these people may not be able to stop the utilization behavior, an automatic mechanism that tends to make us interact with all the objects that are in our perceptual sphere.

Churchland (2006) and Suhler and Churchland (2009) proposed a hypothesis concerning the neural basis for control, which can bridge the gap between higher-order concepts and brain mechanisms. As she wrote,

Perhaps we can identify various parameters of the normal profile of being in control, which would include specific connectivity patterns between amygdala, orbitofrontal cortex, and insula, between anterior cingulate gyrus and prefrontal cortex, and so forth. Other parameters would identify, for each of the six non specific systems [identified via the neurotransmitter secreted at the axon terminals: serotonin, dopamine, norepinephrine, epinephrine, histamine and acetylcholine], the normal distribution of axon terminals and the normal patterns of neurotransmitter release, uptake, and co-localization with other neurotransmitters such as glutamate. Levels of various hormones would specify another set of parameters. Yet other parameters contrast the immature with adult pattern of synaptic density and axon myelinization. At the current stage of neuroscience, we can identify the normal range for these parameters only roughly, not precisely ( Churchland, 2006 ).

This hypothesis would allow for specific brain correlates of a free will index based on the executive functions-guided self-control and even, hypothetically, a direct brain measure of being in control For example, a recent study ( Bartelle et al., 2016 ) highlights the possibility of having MRI imaging of dopamine release thanks to a engineered protein that binds to the neurotransmitter and works as a MRI-visible probe. As the authors put it, “one could imagine a future in which molecular fMRI is used to determine brain-wide neurochemicals maps corresponding to a universe of stimuli and behavioral programs”. Even though one should always consider that there isn’t perfect correspondence between higher-order concepts and putative neural correlates.

In particular, one must consider that what matters in interpersonal relations and in law, to give two examples of practical relevance of free will, is freedom as actually performed: that is, freedom as it can be observed and with some approximation, also measured through a series of psychological tests. This does not mean that the same level of freedom manifested in behavior matches the same level of activation of the related brain areas. However, one can investigate the brain causes of “freedom deficit” compared with the average shown by relevant samples of the population, and so come to a progressive refinement of the research on the neural bases of free will.

Another example is given by the investigation of the role of the cholinergic interneurons in behavioral flexibility ( Aoki et al., 2015 ). This class of neurons seem to be connected to survive in an ever-changing world, which requires behaving flexibly. Flexibility can be assessed (and measured) at a behavioral level, but cerebral mechanisms remain largely unknown. Using conventional tests on behavioral flexibility, which require animals to shift their attention from one stimulus property (e.g., color) to another (e.g., shape), researchers probed the effects of an immunotoxin-induced lesion of cholinergic interneurons in the striatum.

A selective cholinergic ablation was made by means of injections of immunotoxin, which targeted neurons containing choline acetyltransferase in the dorsomedial or ventral striatum. A control group was instead injected with saline. “When encountering a change of behavioral rules after the set-shift, either lesion made animals stick to a previously correct but now invalid response strategy. They also showed less exploratory behavior toward finding a new rule. Most interestingly, ablation of cholinergic neurons in the dorsomedial striatum impaired a shift of set when it required attention to a previously irrelevant cue. On the other hand, ventral cholinergic lesions had an effect on a shift in which a novel stimulus was introduced as a new directional cue” ( Aoki et al., 2015 ). Animals thus can be taken to be “less free” when striatal cholinergic interneurons don’t work properly.

This last example serves to indicate how to bridge the gap between overt behaviors (to which we tend to attribute the property of freedom) with neuronal mechanisms that are clearly identifiable and even manipulable. In fact, it is not so important to look at the conscious aspect of a single proximal mechanism, but rather to consider the manifest behavioral effect that the considered mechanism helps to produce. This way there would be a paradigm shift with respect to the neuroscience research on free will, which seems to have long been too closely linked to the falsification of the theoretical assumption that an action is free only if it has a beginning that is fully controlled by a conscious process. The proposal, I am making here has only the ambition to be a potentially helpful contribution to theoretical debate and empirical research, although its limits are very clear. First, it focuses on a specific part of what is intuitively called “free will”, relating it to the idea of “capacity”. Second, it proposes to measure free will at a psychological level by means of a unitary index that inevitably misses many nuances of the notion and the relative capacity. Furthermore, the search for the neural correlated of such capacities implies not only the identification of causal mechanisms, but also the consideration of many cerebral areas. All of this makes things harder compared to approaches à la Libet. Nevertheless, there is manifest advantage: there is a greater degree of realism and adherence to the actual behavioral manifestation of what we call “free will”.

Free will is an elusive but crucial concept. For many years we have known that the functioning of our brain has to do not only with the belief that we have free will but also with the existence of free will itself. Evidence of the unconscious start of movement, highlighted by the RP signal, has led to believe that we had reached an experimental proof of the non-existence of free will—which many already claimed at a theoretical level based on the argument of the incompatibility between determinism and freedom. Along with other evidence provided by experimental psychology, the branch of studies inaugurated by Libet has contributed to seeing free will as an illusion: this view seemed to be reliably supported by science, and in particular by neuroscience. Recent studies, however, seem to question this paradigm, which sees the initiation and conscious control of the action as the first requirement of free will, allegedly proving that there are no such things.

The stochastic models and the models of evidence accumulation consider decision as the crossing of a threshold of activity in specific brain regions. They do not restore the idea of conscious control but turn away from the previous paradigm. These studies cannot yet fully explain how the intention to perform an action arises in the brain, but they better account for the complexity of the process. In particular, they recognize the role of the spontaneous activity of the brain, of external cues and other factors—including those that might be called “will” and “reasons” (which, however, do not currently have precisely identified neural correlates)—in reaching the critical threshold. Studies that show how we can consciously block movements whose preparation has already begun unconsciously, then, indicate how the subject is able to exercise a form of control, whose genesis however is still unclear.

One could state that free “decision-making draws upon a rich history of accumulated information, manifested in preferences, attitudes and motivations, and is related to the current internal and external environment in which we act. Complete absence of context is impossible” ( Bode et al., 2014 ). In this framework, I have here proposed to integrate neuroscientific research on free will by connecting higher-level concepts with their neural correlates through a psychological operationalization in terms of skills and cognitive functions that do not necessarily imply a continuous conscious control over the decision-making and action process. This may also allow one to create a quantitative index, albeit still quite rudimentary, of the degree of freedom of each subject. This freedom would be specifically defined and therefore may not perfectly coincide with the intuitive concept of free will. Starting from these functional indicators, which psychology has well clarified, one could then move on to investigate the precise neural correlates for a different and (possibly) more fundamental level of explanation in terms of brain processes that enable the executive functions.

According to Craver (2007) , a mechanistic explanation is able to lead to an inter-field integration. There are two relevant aspects to this approach. The functional knowledge that can be drawn from psychological research is a tool to identify neural mechanisms; the knowledge of the brain structure can guide the construction of far more sophisticated psychological models ( Bechtel and Mundale, 1999 ). The index of free will that I am proposing ( Lavazza and Inglese, 2015 )—despite surely needing further refinement—might be useful to explore the brain mechanisms that underlie what appears in behavior as “free will”, which no longer seems to be an illusion, not even for neuroscientific research.

Author Contributions

AL confirms being the sole contributor of this work and approved it for publication.

Conflict of Interest Statement

The author declares that the research was conducted in the absence of any commercial or financial relationships that could be construed as a potential conflict of interest.

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Wong, K.-F., Huk, A. C., Shadlen, M. N., and Wang, X.-J. (2007). Neural circuit dynamics underlying accumulation of time-varying evidence during perceptual decision making. Front. Comput. Neurosci. 1:6. doi: 10.3389/neuro.10.006.2007

Keywords: readiness potential, unconscious decision, choice prediction, stochastic processes, measurement of freedom, evidence accumulation

Citation: Lavazza A (2016) Free Will and Neuroscience: From Explaining Freedom Away to New Ways of Operationalizing and Measuring It. Front. Hum. Neurosci. 10:262. doi: 10.3389/fnhum.2016.00262

Received: 15 March 2016; Accepted: 18 May 2016; Published: 01 June 2016.

Reviewed by:

Copyright © 2016 Lavazza. This is an open-access article distributed under the terms of the Creative Commons Attribution License (CC BY) . The use, distribution and reproduction in other forums is permitted, provided the original author(s) or licensor are credited and that the original publication in this journal is cited, in accordance with accepted academic practice. No use, distribution or reproduction is permitted which does not comply with these terms.

*Correspondence: Andrea Lavazza, [email protected]

Disclaimer: All claims expressed in this article are solely those of the authors and do not necessarily represent those of their affiliated organizations, or those of the publisher, the editors and the reviewers. Any product that may be evaluated in this article or claim that may be made by its manufacturer is not guaranteed or endorsed by the publisher.

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Free Will: Now You Have It, Now You Don’t

By Dennis Overbye

• Jan. 2, 2007

I was a free man until they brought the dessert menu around. There was one of those molten chocolate cakes, and I was suddenly being dragged into a vortex, swirling helplessly toward caloric doom, sucked toward the edge of a black (chocolate) hole. Visions of my father’s heart attack danced before my glazed eyes. My wife, Nancy, had a resigned look on her face.

The outcome, endlessly replayed whenever we go out, is never in doubt, though I often cover my tracks by offering to split my dessert with the table. O.K., I can imagine what you’re thinking. There but for the grace of God .

Having just lived through another New Year’s Eve, many of you have just resolved to be better, wiser, stronger and richer in the coming months and years. After all, we’re free humans, not slaves, robots or animals doomed to repeat the same boring mistakes over and over again. As William James wrote in 1890, the whole “sting and excitement” of life comes from “our sense that in it things are really being decided from one moment to another, and that it is not the dull rattling off of a chain that was forged innumerable ages ago.” Get over it, Dr. James. Go get yourself fitted for a new chain-mail vest. A bevy of experiments in recent years suggest that the conscious mind is like a monkey riding a tiger of subconscious decisions and actions in progress, frantically making up stories about being in control.

As a result, physicists, neuroscientists and computer scientists have joined the heirs of Plato and Aristotle in arguing about what free will is, whether we have it, and if not, why we ever thought we did in the first place.

“Is it an illusion? That’s the question,” said Michael Silberstein, a science philosopher at Elizabethtown College in Pennsylvania. Another question, he added, is whether talking about this in public will fan the culture wars.

“If people freak at evolution, etc.,” he wrote in an e-mail message, “how much more will they freak if scientists and philosophers tell them they are nothing more than sophisticated meat machines, and is that conclusion now clearly warranted or is it premature?”

Daniel C. Dennett, a philosopher and cognitive scientist at Tufts University who has written extensively about free will, said that “when we consider whether free will is an illusion or reality, we are looking into an abyss. What seems to confront us is a plunge into nihilism and despair.”

Mark Hallett, a researcher with the National Institute of Neurological Disorders and Stroke, said, “Free will does exist, but it’s a perception, not a power or a driving force. People experience free will. They have the sense they are free.

“The more you scrutinize it, the more you realize you don’t have it,” he said.

That is hardly a new thought. The German philosopher Arthur Schopenhauer said, as Einstein paraphrased it, that “a human can very well do what he wants, but cannot will what he wants.”

Einstein, among others, found that a comforting idea. “This knowledge of the non-freedom of the will protects me from losing my good humor and taking much too seriously myself and my fellow humans as acting and judging individuals,” he said.

How comforted or depressed this makes you might depend on what you mean by free will. The traditional definition is called “libertarian” or “deep” free will. It holds that humans are free moral agents whose actions are not predetermined. This school of thought says in effect that the whole chain of cause and effect in the history of the universe stops dead in its tracks as you ponder the dessert menu.

At that point, anything is possible. Whatever choice you make is unforced and could have been otherwise, but it is not random. You are responsible for any damage to your pocketbook and your arteries.

“That strikes many people as incoherent,” said Dr. Silberstein, who noted that every physical system that has been investigated has turned out to be either deterministic or random. “Both are bad news for free will,” he said. So if human actions can’t be caused and aren’t random, he said, “It must be — what — some weird magical power?”

People who believe already that humans are magic will have no problem with that.

But whatever that power is — call it soul or the spirit — those people have to explain how it could stand independent of the physical universe and yet reach from the immaterial world and meddle in our own, jiggling brain cells that lead us to say the words “molten chocolate.”

A vote in favor of free will comes from some physicists, who say it is a prerequisite for inventing theories and planning experiments.

That is especially true when it comes to quantum mechanics, the strange paradoxical theory that ascribes a microscopic randomness to the foundation of reality. Anton Zeilinger, a quantum physicist at the University of Vienna, said recently that quantum randomness was “not a proof, just a hint, telling us we have free will.”

Is there any evidence beyond our own intuitions and introspections that humans work that way?

Two Tips of the Iceberg

In the 1970s, Benjamin Libet, a physiologist at the University of California, San Francisco, wired up the brains of volunteers to an electroencephalogram and told the volunteers to make random motions, like pressing a button or flicking a finger, while he noted the time on a clock.

Dr. Libet found that brain signals associated with these actions occurred half a second before the subject was conscious of deciding to make them.

The order of brain activities seemed to be perception of motion, and then decision, rather than the other way around.

In short, the conscious brain was only playing catch-up to what the unconscious brain was already doing. The decision to act was an illusion, the monkey making up a story about what the tiger had already done.

Dr. Libet’s results have been reproduced again and again over the years, along with other experiments that suggest that people can be easily fooled when it comes to assuming ownership of their actions. Patients with tics or certain diseases, like chorea, cannot say whether their movements are voluntary or involuntary, Dr. Hallett said.

In some experiments, subjects have been tricked into believing they are responding to stimuli they couldn’t have seen in time to respond to, or into taking credit or blame for things they couldn’t have done. Take, for example, the “voodoo experiment” by Dan Wegner, a psychologist at Harvard, and Emily Pronin of Princeton. In the experiment, two people are invited to play witch doctor.

One person, the subject, puts a curse on the other by sticking pins into a doll. The second person, however, is in on the experiment, and by prior arrangement with the doctors, acts either obnoxious, so that the pin-sticker dislikes him, or nice.

After a while, the ostensible victim complains of a headache. In cases in which he or she was unlikable, the subject tended to claim responsibility for causing the headache, an example of the “magical thinking” that makes baseball fans put on their rally caps.

“We made it happen in a lab,” Dr. Wegner said.

Is a similar sort of magical thinking responsible for the experience of free will?

“We see two tips of the iceberg, the thought and the action,” Dr. Wegner said, “and we draw a connection.”

But most of the action is going on beneath the surface. Indeed, the conscious mind is often a drag on many activities. Too much thinking can give a golfer the yips. Drivers perform better on automatic pilot. Fiction writers report writing in a kind of trance in which they simply take dictation from the voices and characters in their head, a grace that is, alas, rarely if ever granted nonfiction writers.

Naturally, almost everyone has a slant on such experiments and whether or not the word “illusion” should be used in describing free will. Dr. Libet said his results left room for a limited version of free will in the form of a veto power over what we sense ourselves doing. In effect, the unconscious brain proposes and the mind disposes.

In a 1999 essay, he wrote that although this might not seem like much, it was enough to satisfy ethical standards. “Most of the Ten Commandments are ‘do not’ orders,” he wrote.

But that might seem a pinched and diminished form of free will.

Good Intentions

Dr. Dennett, the Tufts professor, is one of many who have tried to redefine free will in a way that involves no escape from the materialist world while still offering enough autonomy for moral responsibility, which seems to be what everyone cares about.

The belief that the traditional intuitive notion of a free will divorced from causality is inflated, metaphysical nonsense, Dr. Dennett says reflecting an outdated dualistic view of the world.

Rather, Dr. Dennett argues, it is precisely our immersion in causality and the material world that frees us. Evolution, history and culture, he explains, have endowed us with feedback systems that give us the unique ability to reflect and think things over and to imagine the future. Free will and determinism can co-exist.

“All the varieties of free will worth having, we have,” Dr. Dennett said.

“We have the power to veto our urges and then to veto our vetoes,” he said. “We have the power of imagination, to see and imagine futures.”

In this regard, causality is not our enemy but our friend, giving us the ability to look ahead and plan. “That’s what makes us moral agents,” Dr. Dennett said. “You don’t need a miracle to have responsibility.”

Other philosophers disagree on the degree and nature of such “freedom.” Their arguments partly turn on the extent to which collections of things, whether electrons or people, can transcend their origins and produce novel phenomena.

These so-called emergent phenomena, like brains and stock markets, or the idea of democracy, grow naturally in accordance with the laws of physics, so the story goes. But once they are here, they play by new rules, and can even act on their constituents, as when an artist envisions a teapot and then sculpts it — a concept sometimes known as “downward causation.” A knowledge of quarks is no help in predicting hurricanes — it’s physics all the way down. But does the same apply to the stock market or to the brain? Are the rules elusive just because we can’t solve the equations or because something fundamentally new happens when we increase numbers and levels of complexity?

Opinions vary about whether it will ultimately prove to be physics all the way down, total independence from physics, or some shade in between, and thus how free we are. Dr. Silberstein, the Elizabethtown College professor, said, “There’s nothing in fundamental physics by itself that tells us we can’t have such emergent properties when we get to different levels of complexities.”

He waxed poetically as he imagined how the universe would evolve, with more and more complicated forms emerging from primordial quantum muck as from an elaborate computer game, in accordance with a few simple rules: “If you understand, you ought to be awestruck, you ought to be bowled over.”

George R. F. Ellis, a cosmologist at the University of Cape Town, said that freedom could emerge from this framework as well. “A nuclear bomb, for example, proceeds to detonate according to the laws of nuclear physics,” he explained in an e-mail message. “Whether it does indeed detonate is determined by political and ethical considerations, which are of a completely different order.”

I have to admit that I find these kind of ideas inspiring, if not liberating. But I worry that I am being sold a sort of psychic perpetual motion machine. Free wills, ideas, phenomena created by physics but not accountable to it. Do they offer a release from the chains of determinism or just a prescription for a very intricate weave of the links?And so I sought clarity from mathematicians and computer scientists. According to deep mathematical principles, they say, even machines can become too complicated to predict their own behavior and would labor under the delusion of free will.

If by free will we mean the ability to choose, even a simple laptop computer has some kind of free will, said Seth Lloyd, an expert on quantum computing and professor of mechanical engineering at the Massachusetts Institute of Technology.

Every time you click on an icon, he explained, the computer’s operating system decides how to allocate memory space, based on some deterministic instructions. But, Dr. Lloyd said, “If I ask how long will it take to boot up five minutes from now, the operating system will say ‘I don’t know, wait and see, and I’ll make decisions and let you know.’ ”

Why can’t computers say what they’re going to do? In 1930, the Austrian philosopher Kurt Gödel proved that in any formal system of logic, which includes mathematics and a kind of idealized computer called a Turing machine, there are statements that cannot be proven either true or false. Among them are self-referential statements like the famous paradox stated by the Cretan philosopher Epimenides, who said that all Cretans are liars: if he is telling the truth, then, as a Cretan, he is lying.

One implication is that no system can contain a complete representation of itself, or as Janna Levin, a cosmologist at Barnard College of Columbia University and author of the 2006 novel about Gödel, “A Madman Dreams of Turing Machines,” said: “Gödel says you can’t program intelligence as complex as yourself. But you can let it evolve. A complex machine would still suffer from the illusion of free will.”

Another implication is there is no algorithm, or recipe for computation, to determine when or if any given computer program will finish some calculation. The only way to find out is to set it computing and see what happens. Any way to find out would be tantamount to doing the calculation itself.

“There are no shortcuts in computation,” Dr. Lloyd said.

That means that the more reasonably you try to act, the more unpredictable you are, at least to yourself, Dr. Lloyd said. Even if your wife knows you will order the chile rellenos, you have to live your life to find out.

To him that sounds like free will of a sort, for machines as well as for us. Our actions are determined, but so what? We still don’t know what they will be until the waiter brings the tray.

That works for me, because I am comfortable with so-called physicalist reasoning, and I’m always happy to leverage concepts of higher mathematics to cut through philosophical knots.

The Magician’s Spell

So what about Hitler?

The death of free will, or its exposure as a convenient illusion, some worry, could wreak havoc on our sense of moral and legal responsibility. According to those who believe that free will and determinism are incompatible, Dr. Silberstein said in an e-mail message, it would mean that “people are no more responsible for their actions than asteroids or planets.” Anything would go.

Dr. Wegner of Harvard said: “We worry that explaining evil condones it. We have to maintain our outrage at Hitler. But wouldn’t it be nice to have a theory of evil in advance that could keep him from coming to power?”

He added, “A system a bit more focused on helping people change rather than paying them back for what they’ve done might be a good thing.”

Dr. Wegner said he thought that exposing free will as an illusion would have little effect on people’s lives or on their feelings of self-worth. Most of them would remain in denial.

“It’s an illusion, but it’s a very persistent illusion; it keeps coming back,” he said, comparing it to a magician’s trick that has been seen again and again. “Even though you know it’s a trick, you get fooled every time. The feelings just don’t go away.”

In an essay about free will in 1999, Dr. Libet wound up quoting the writer Isaac Bashevis Singer, who once said in an interview with the Paris Review, “The greatest gift which humanity has received is free choice. It is true that we are limited in our use of free choice. But the little free choice we have is such a great gift and is potentially worth so much that for this itself, life is worthwhile living.”

I could skip the chocolate cake, I really could, but why bother? Waiter!

An article in Science Times on Tuesday about the debate over free will misstated the location of Elizabethtown College, where Michael Silberstein, who commented on free will and popular culture, is a science philosopher. It is in Pennsylvania, not Maryland.

How we handle corrections

Does Science Really Show Free Will Doesn't Exist? Here's What You Need to Know.

It seems like we have free will. Most of the time, we are the ones who choose what we eat, how we tie our shoelaces and what articles we read on The Conversation.

However, the latest book by Stanford neurobiologist Robert Sapolsky, Determined: A Science of Life Without Free Will, has been receiving a lot of media attention for arguing science shows this is an illusion .

Sapolsky summarizes the latest scientific research relevant to determinism: the idea that we're causally "determined" to act as we do because of our histories – and couldn't possibly act any other way.

According to determinism, just as a rock that is dropped is determined to fall due to gravity, your neurons are determined to fire a certain way as a direct result of your environment, upbringing, hormones, genes, culture and myriad other factors outside your control. And this is true regardless of how "free" your choices seem to you.

Sapolsky also says that because our behaviour is determined in this way, nobody is morally responsible for what they do. He believes while we can lock up murderers to keep others safe, they technically don't deserve to be punished.

This is quite a radical position. It's worth asking why only 11% of philosophers agree with Sapolsky, compared with the 60% who think being causally determined is compatible with having free will and being morally responsible.

Have these " compatibilists " failed to understand the science? Or has Sapolsky failed to understand free will?

Is determinism incompatible with free will?

"Free will" and "responsibility" can mean a variety of different things depending on how you approach them.

Many people think of free will as having the ability to choose between alternatives. Determinism might seem to threaten this, because if we are causally determined then we lack any real choice between alternatives; we only ever make the choice we were always going to make.

But there are counterexamples to this way of thinking. For instance, suppose when you started reading this article someone secretly locked your door for 10 seconds, preventing you from leaving the room during that time. You, however, had no desire to leave anyway because you wanted to keep reading – so you stayed where you are. Was your choice free?

Many would argue even though you lacked the option to leave the room, this didn't make your choice to stay unfree. Therefore, lacking alternatives isn't what decides whether you lack free will. What matters instead is how the decision came about.

The trouble with Sapolsky's arguments, as free will expert John Martin Fischer explains , is he doesn't actually present any argument for why his conception of free will is correct.

He simply defines free will as being incompatible with determinism, assumes this absolves people of moral responsibility, and spends much of the book describing the many ways our behaviours are determined. His arguments can all be traced back to his definition of "free will".

Compatibilists believe humans are agents. We live lives with "meaning", have an understanding of right and wrong, and act for moral reasons. This is enough to suggest most of us, most of the time, have a certain type of freedom and are responsible for our actions (and deserving of blame) – even if our behaviours are "determined".

Compatibilists would point out that being constrained by determinism isn't the same as being constrained to a chair by a rope. Failing to save a drowning child because you were tied up is not the same as failing to save a drowning child because you were "determined" not to care about them. The former is an excuse. The latter is cause for condemnation.

Incompatibilists must defend themselves better

Some readers sympathetic to Sapolsky might feel unconvinced. They might say your decision to stay in the room, or ignore the child, was still caused by influences in your history that you didn't control – and therefore you weren't truly free to choose.

However, this doesn't prove that having alternatives or being "undetermined" is the only way we can count as having free will. Instead, it assumes they are. From the compatibilists' point of view, this is cheating.

Compatibilists and incompatibilists both agree that, given determinism is true, there is a sense in which you lack alternatives and could not do otherwise.

However, incompatibilists will say you therefore lack free will, whereas compatibilists will say you still possess free will because that sense of "lacking alternatives" isn't what undermines free will – and free will is something else entirely.

They say as long as your actions came from you in a relevant way (even if "you" were "determined" by other things), you count as having free will. When you're tied up by a rope, the decision to not save the drowning child doesn't come from you. But when you just don't care about the child, it does.

By another analogy, if a tree falls in a forest and nobody is around, one person may say no auditory senses are present, so this is incompatible with sound existing. But another person may say even though no auditory senses are present, this is still compatible with sound existing because "sound" isn't about auditory perception – it's about vibrating atoms.

Both agree nothing is heard, but disagree on what factors are relevant to determining the existence of "sound" in the first place. Sapolsky needs to show why his assumptions about what counts as free will are the ones relevant to moral responsibility. As philosopher Daniel Dennett once put it, we need to ask which " varieties of free will [are] worth wanting ".

Free will isn't a scientific question

The point of this back and forth isn't to show compatibilists are right. It is to highlight there's a nuanced debate to engage with. Free will is a thorny issue. Showing nobody is responsible for what they do requires understanding and engaging with all the positions on offer. Sapolsky doesn't do this.

Sapolsky's broader mistake seems to be assuming his questions are purely scientific: answered by looking just at what the science says. While science is relevant, we first need some idea of what free will is (which is a metaphysical question ) and how it relates to moral responsibility (a normative question ). This is something philosophers have been interrogating for a very long time .

Adam Piovarchy , Research Associate, Institute for Ethics and Society, University of Notre Dame Australia

This article is republished from The Conversation under a Creative Commons license. Read the original article .

Reviewed by Psychology Today Staff

Free will is the idea that humans have the ability to make their own choices and determine their own fates. Is a person’s will free, or are people's lives in fact shaped by powers outside of their control? The question of free will has long challenged philosophers and religious thinkers, and scientists have examined the problem from psychological and neuroscientific perspectives as well.

• Does Free Will Exist?
• Why Beliefs About Free Will Matter

Scientists have investigated the concept of human agency at the level of neural circuitry, and some findings have been taken as evidence that conscious decisions are not truly “free.” Free will skeptics argue that the subjective sense of free will is an illusion. Yet many scholars, as well as ordinary people, still profess a belief in free will, even if they acknowledge that choices are partly shaped by forces outside of one's control.

Behavioral science has made plain that individuals’ behavioral tendencies are influenced by genetics , as well as by factors in the environment that may be outside of a person’s control. This suggests that there are, at least, some constraints on the range of decisions and behaviors a person will be inclined to make (or even to consider) in any given situation. Challengers of the idea that people act the way they do due to conscious, unconstrained choices also point to evidence that unconscious brain activity can partly predict a choice before a conscious decision is made. And some have sought to logically refute the argument that choices necessarily demonstrate free will.

While there are many reasons to believe that a person’s will is not completely free of influence, there is not a scientific consensus against free will. Some use the term “free will” in a looser sense to reflect that conscious decisions play a role in the outcomes of a person’s life—even if those are shaped by innate dispositions or randomness. (Critics of the concept of free will might simply call this kind of decision-making “will,” or volition.) Even when unconscious processes help determine a person’s conscious behavior, some argue, such processes can still be thought of as part of an individual’s will.

Determinism is the idea that every event, including every human action, is the result of previous events and the laws of nature. A belief in determinism that includes a rejection of free will has been called “hard determinism.”

From a deterministic perspective, there is only one possible way that future events can unfold based on what has already occurred and the rules that govern the universe—though that doesn’t mean such events can necessarily be predicted by humans. Someone who believes in free will because they do not take determinism for granted is called, in philosophy , a “libertarian.”

Yes. This is called “compatibilism” or “soft determinism.” A compatibilist believes that even though events are predetermined, there is still some version of free will at work in decision-making . An incompatibilist argues that only determinism or free will can be true.

Whether free will exists or not, belief in free will is very real. Does it matter if a person believes that her choices are completely her own, and that other people’s choices are freely made, too? Psychologists have explored the connections between free will beliefs—often gauged by agreement with statements like “I am in charge of my actions even when my life’s circumstances are difficult” and, simply, “I have free will”—and people’s attitudes about decision-making, blame, and other variables of consequence.

The more people agree with claims of free will , some research suggests, the more they tend to favor internal rather than external explanations for someone else’s behavior. This may include, for example, learning of someone’s immoral deed and agreeing more strongly that it was a result of the person’s character and less that factors like social norms are to blame. (A study of whether reducing free-will beliefs influenced sentencing decisions by actual judges, however, did not show any effect. )

One idea proposed in philosophy is that systems of morality would collapse without a common belief that each person is responsible for his actions—and thus deserves reward or punishment for them. In this view, there is value in maintaining belief in free will, even if free will is in fact an illusion. Others argue that morality can exist in the absence of free-will belief, or that belief in free will actually promotes harmful outcomes such as intolerance and revenge-seeking. Some psychology research has been cited as suggesting that disbelief in free will increases dishonest behavior, but subsequent experiments have called this finding into question.

Mental illness can be thought of, in a sense, as involving additional constraints on the freedom of a person’s will (in the form of rigid thought patterns or compulsions, for instance), beyond the usual factors that shape thinking and behavior. Belief in free will, it has been argued, may contribute to the stigma attached to mental illness by obscuring the role of underlying biological and environmental causes.

There is limited evidence that people who believe more strongly in free will may tend to perceive at least some kinds of choices—such as buying electronics or deciding what to watch on TV—as easier to make, and that they may enjoy making choices more.

Two concepts from psychology that bear similarity to belief in free will are “ locus of control ” and “ self-efficacy .” Locus of control refers to a person’s belief about how much power he has over his life—how important factors like intentions and hard work seem to be compared to external forces such as good luck or the actions of others. Self-efficacy is a person’s sense of her ability to perform at a certain level so as to influence events that affect them. While all of these concepts relate to the factors that steer a person’s life, they are distinct—one can doubt that humans have free will, for example, and still be confident in her ability to win a competition .

Are you easily triggered and/or have a tendency to work against yourself?

Fear of death is the main driver of anxiety and depression in humans. Recent research demonstrates that we can extend human life despite limitations.

The brain has three processing stages associated with consciousness. Here, we focus on Stage 2, "the conscious field."

There are three stages of processing in the brain, starting with unconscious processes preceding, and giving rise to, the construction of the “conscious field."

Algorithms are designed to keep your attention engaged and programmed to be passive and predictable. Fortunately, mindfulness connects you to this moment with joy and spontaneity.

As their child's adolescent transformation begins, parents can feel helpless in the face of developmental change, but they still have many sources of influence to draw upon.

This post explores a different way to view the trendy topic of gut health by exploring the gut-brain connection and how to trust your gut with greater confidence.

People have "sold their soul" in books, songs, and even real life. For a non-believer a soul is worth $0 — but how much should a believer pay for one?

When smart people looking at the same evidence disagree, the reason might be that they define basic concepts differently and talk past each other.

Focusing on our "narrative self" limits our understanding.

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• National Center for Biotechnology Information - PubMed Central - Free Will and Neuroscience: From Explaining Freedom Away to New Ways of Operationalizing and Measuring It
• Stanford Encyclopedia of Philosophy - Free Will
• University of Notre Dame - Is free will possible?
• Nature - Is free will an illusion?
• Psychology Today - Free Will
• Routledge Encyclopedia of Philosophy - Free Will
• Internet Encyclopedia of Philosophy - Free Will
• Frontiers - Frontiers in Human Neuroscience - Free Will and Neuroscience: From explaining freedom away to new ways of operationalizing and measuring it
• Simply Psychology - Freewill vs Determinism in Psychology
• Humanities LibreTexts - Free Will, Determinism, and Responsibility
• University of Central Florida Pressbooks - The problem of free will and determinism

free will , in philosophy and science , the supposed power or capacity of humans to make decisions or perform actions independently of any prior event or state of the universe. Arguments for free will have been based on the subjective experience of freedom, on sentiments of guilt, on revealed religion , and on the common assumption of individual moral responsibility that underlies the concepts of law, reward, punishment, and incentive. In theology , the existence of free will must be reconciled with God’s omniscience and benevolence and with divine grace , which allegedly is necessary for any meritorious act. A prominent feature of existentialism is the concept of a radical, perpetual, and frequently agonizing freedom of choice . Jean-Paul Sartre (1905–80), for example, spoke of the individual “condemned to be free.”

The existence of free will is denied by some proponents of determinism , the thesis that every event in the universe is causally inevitable. Determinism entails that, in a situation in which people make a certain decision or perform a certain action, it is impossible that they could have made any other decision or performed any other action. In other words, it is never true that people could have decided or acted otherwise than they actually did. Philosophers and scientists who believe that determinism in this sense is incompatible with free will are known as “hard” determinists.

In contrast, so-called “soft” determinists, also called compatibilists, believe that determinism and free will are compatible after all. In most cases, soft determinists attempt to achieve this reconciliation by subtly revising or weakening the commonsense notion of free will. Contemporary soft determinists have included the English philosopher G.E. Moore (1873–1958), who held that acting freely means only that one would have acted otherwise had one decided to do so (even if, in fact, one could not have decided to do so), and the American philosopher Harry Frankfurt (born 1929), who has argued that acting freely amounts to identifying with or approving of one’s own desires (even if those desires are such that one cannot help but act on them).

The extreme alternative to determinism is indeterminism , the view that at least some events have no deterministic cause but occur randomly, or by chance. Indeterminism is supported to some extent by research in  quantum mechanics , which suggests that some events at the quantum level are in principle unpredictable (and therefore random). Philosophers and scientists who believe that the universe is indeterministic and that humans possess free will are known as “libertarians” (libertarianism in this sense is not to be confused with the school of political philosophy called  libertarianism ). Although it is possible to hold that the universe is indeterministic and that human actions are nevertheless determined, few contemporary philosophers defend this view.

Libertarianism is vulnerable to what is called the “intelligibility” objection, which points out that people can have no more control over a purely random action than they have over an action that is deterministically inevitable; in neither case does free will enter the picture. Hence, if human actions are indeterministic, free will does not exist. See also free will and moral responsibility .

Stanford scientist, after decades of study, concludes: We don’t have free will

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Before epilepsy was understood to be a neurological condition, people believed it was caused by the moon, or by phlegm in the brain. They condemned seizures as evidence of witchcraft or demonic possession, and killed or castrated sufferers to prevent them from passing tainted blood to a new generation.

Today we know epilepsy is a disease. By and large, it’s accepted that a person who causes a fatal traffic accident while in the grip of a seizure should not be charged with murder.

That’s good, says Stanford University neurobiologist Robert Sapolsky . That’s progress. But there’s still a long way to go.

After more than 40 years studying humans and other primates, Sapolsky has reached the conclusion that virtually all human behavior is as far beyond our conscious control as the convulsions of a seizure, the division of cells or the beating of our hearts.

This means accepting that a man who shoots into a crowd has no more control over his fate than the victims who happen to be in the wrong place at the wrong time. It means treating drunk drivers who barrel into pedestrians just like drivers who suffer a sudden heart attack and veer out of their lane.

“The world is really screwed up and made much, much more unfair by the fact that we reward people and punish people for things they have no control over,” Sapolsky said. “We’ve got no free will. Stop attributing stuff to us that isn’t there.”

We’ve got no free will. Stop attributing stuff to us that isn’t there.

— Stanford neurobiologist Robert Sapolsky

Sapolsky, a MacArthur “genius” grant winner , is extremely aware that this is an out-there position. Most neuroscientists believe humans have at least some degree of free will. So do most philosophers and the vast majority of the general population. Free will is essential to how we see ourselves, fueling the satisfaction of achievement or the shame of failing to do the right thing.

Saying that people have no free will is a great way to start an argument. This is partly why Sapolsky, who describes himself as “majorly averse to interpersonal conflict,” put off writing his new book “Determined: A Science of Life Without Free Will.”

Sapolsky, 66, has a mild demeanor and a Jerry Garcia beard. For more than three decades, he escaped the politics of academia to study baboons in rural Kenya for a few months every year.

“I’m really, really, really trying not to sound like a combative jerk in the book,” he said. “I deal with human complexities by going and living in a tent. So yeah, I’m not up for a lot of brawls about this.”

Analyzing human behavior through the lens of any single discipline leaves room for the possibility that people choose their actions, he says. But after a long cross-disciplinary career, he feels it’s intellectually dishonest to write anything other than what he sees as the unavoidable conclusion: Free will is a myth, and the sooner we accept that, the more just our society will be.

“Determined,” which comes out today, builds on Sapolsky’s 2017 bestseller “Behave: The Biology of Humans at Our Best and Worst,” which won the Los Angeles Times Book Prize and a slew of other accolades.

The book breaks down the neurochemical influences that contribute to human behaviors, analyzing the milliseconds to centuries preceding, say, the pulling of a trigger or the suggestive touch on an arm.

“Determined” goes a step further. If it’s impossible for any single neuron or any single brain to act without influence from factors beyond its control, Sapolsky argues, there can be no logical room for free will.

Many people with even a passing familiarity with human biology can comfortably agree with this — up to a point.

We know we make worse decisions when hungry , stressed or scared . We know our physical makeup is influenced by the genes inherited from distant ancestors and by our mothers’ health during her pregnancy. Abundant evidence indicates that people who grew up in homes marked by chaos and deprivation will perceive the world differently and make different choices than people raised in safe, stable, resource-rich environments. A lot of important things are beyond our control.

But, like — everything? We have no meaningful command over our choice of careers, romantic partners or weekend plans? If you reach out right now and pick up a pen, was even that insignificant action somehow preordained?

Yes, Sapolsky says, both in the book and to the countless students who have asked the same question during his office hours. What the student experiences as a decision to grab the pen is preceded by a jumble of competing impulses beyond his or her conscious control. Maybe their pique is heightened because they skipped lunch; maybe they’re subconsciously triggered by the professor’s resemblance to an irritating relative.

Then look at the forces that brought them to the professor’s office, feeling empowered to challenge a point. They’re more likely to have had parents who themselves were college educated, more likely to hail from an individualistic culture rather than a collective one. All of those influences subtly nudge behavior in predictable ways.

You may have had the uncanny experience of talking about an upcoming camping trip with a friend, only to find yourself served with ads for tents on social media later. Your phone didn’t record your conversation, even if that’s what it feels like. It’s just that the collective record of your likes, clicks, searches and shares paints such a detailed picture of your preferences and decision-making patterns that algorithms can predict — often with unsettling accuracy — what you are going to do.

Something similar happens when you reach for that pen, Sapolsky says. So many factors beyond your conscious awareness brought you to that pen that it’s hard to say how much you “chose” to pick it up at all.

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Sapolsky was raised in an Orthodox Jewish household in Brooklyn, the son of immigrants from the former Soviet Union.

Biology called to him early — by grade school he was writing fan letters to primatologists and lingering in front of the taxidermied gorillas at the American Museum of Natural History — but religion shaped life at home.

That all changed on a single night in his early teens, he says. While grappling with questions of faith and identity, he was struck by an epiphany that kept him awake until dawn and reshaped his future: God is not real, there is no free will, and we primates are pretty much on our own.

“That was kind of a big day,” he said with a chuckle, “and it’s been tumultuous since then.”

Skeptics could seize on this to rebut his arguments: If we aren’t free to choose our actions or beliefs, how does a boy from a deeply religious conservative home become a self-professed liberal atheist?

Change is always possible, he argues, but it comes from external stimuli. Sea slugs can learn to reflexively retreat from an electrical shock. Through the same biochemical pathways, humans are changed by exposure to external events in ways we rarely see coming.

Imagine, he offers, a group of friends that goes to see a biopic about an inspiring activist. One applies the next day to join the Peace Corps. One is struck by the beautiful cinematography and signs up for a filmmaking course. The rest are annoyed they didn’t see a Marvel film.

All of the friends were primed to respond as they did when they sat down to watch. Maybe one had heightened adrenaline from a close call with another car on the drive over; maybe another was in a new relationship and awash in oxytocin, the so-called love hormone. They had different levels of dopamine and serotonin in their brains, different cultural backgrounds, different sensitivities to sensory distractions in the theater. None chose how the stimulus of the film would affect them anymore than the sea slug “decided” to wince in response to a jolt.

For fellow adherents of determinism — the belief that it’s impossible for a person in any situation to have acted differently than they did — Sapolsky’s scientific defense of the cause is welcome.

“Who we are and what we do is ultimately the result of factors beyond our control and because of this we are never morally responsible for our actions in the sense that would make us truly deserving of praise and blame, punishment and reward,” said Gregg Caruso , a philosopher at SUNY Corning who read early drafts of the book. “I am in agreement with Sapolsky that life without belief in free will is not only possible but preferable.”

Caruso is co-director of the Justice Without Retribution Network , which advocates for an approach to criminal activity that prioritizes preventing future harm rather than assigning blame. Focusing on the causes of violent or antisocial behavior instead of fulfilling a desire for punishment, he said, “will allow us to adopt more humane and effective practices and policies.”

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Theirs is very much a minority viewpoint.

Sapolsky is “a wonderful explainer of complex phenomena,” said Peter U. Tse , a Dartmouth neuroscientist and author of the 2013 book “The Neural Basis of Free Will.” “However, a person can be both brilliant and utterly wrong.”

Neural activity is highly variable, Tse said, with identical inputs often resulting in non-identical responses in individuals and populations. It’s more accurate to think of those inputs as imposing parameters rather than determining specific outcomes. Even if the range of potential outcomes is limited, there’s simply too much variability at play to think of our behavior as predetermined.

What’s more, he said, it’s harmful to do so.

“Those who push the idea that we are nothing but deterministic biochemical puppets are responsible for enhancing psychological suffering and hopelessness in this world,” Tse said.

Even those who believe biology limits our choices are wary of how openly we should embrace that.

Saul Smilansky , a philosopher at the University of Haifa in Israel and author of the book “Free Will and Illusion,” rejects the idea that we can will ourselves to transcend all genetic and environmental constraints. But if we want to live in a just society, we have to believe that we can.

“Losing all belief in free will and moral responsibility would likely be catastrophic,” he said, and encouraging people to do so is “dangerous, even irresponsible.”

A widely cited 2008 study found that people who read passages dismissing the idea of free will were more likely to cheat on a subsequent test. Other studies have found that people who feel less control over their actions care less about making mistakes in their work, and that disbelief in free will leads to more aggression and less helpfulness.

Sapolsky discusses such concerns in his book, ultimately concluding that the effects seen in such experiments are too small and their lack of reproducibility too great to support the idea that civilization will crumble if we think we can’t control our fates.

The more compelling critique, he says, is eloquently articulated in the short story “What’s Expected of Us,” by speculative fiction writer Ted Chiang . The narrator describes a new technology that convinces users their choices are predetermined, a discovery that saps them of their will to live.

“It’s essential that you behave as if your decisions matter,” the narrator warns, “even though you know that they don’t.”

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The greatest risk of abandoning free will, Sapolsky concedes, isn’t that we’ll want to do bad things. It’s that, without a sense of personal agency, we won’t want to do anything.

“It may be dangerous to tell people that they don’t have free will,” Sapolsky said. “The vast majority of the time, I really think it’s a hell of a lot more humane.”

Sapolsky knows he won’t persuade most of his readers. It’s hard to convince people who have been harmed that perpetrators deserve less blame because of their history of poverty. It’s even harder to convince the well-off that their accomplishments deserve less praise because of their history of privilege.

“If you have time to be bummed out by that, you’re one of the lucky ones,” he said.

His true hope, he says, is to increase compassion. Maybe if people understand how thoroughly an early history of trauma can rewire a brain, they’ll stop lusting for harsh punishments. Maybe if someone realizes they have a brain condition like depression or ADHD, they’ll stop hating themselves for struggling with tasks that seem easier for others.

Just as previous generations thought seizures were brought on by witchcraft, some of our current beliefs about personal responsibility may eventually be undone by scientific discovery.

We are machines, Sapolsky argues, exceptional in our ability to perceive our own experiences and feel emotions about them. It is pointless to hate a machine for its failures.

There is only one last thread he can’t resolve.

“It is logically indefensible, ludicrous, meaningless to believe that something ‘good’ can happen to a machine,” he writes. “Nonetheless, I am certain that it is good if people feel less pain and more happiness.”

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Corinne Purtill is a science and medicine reporter for the Los Angeles Times. Her writing on science and human behavior has appeared in the New Yorker, the New York Times, Time Magazine, the BBC, Quartz and elsewhere. Before joining The Times, she worked as the senior London correspondent for GlobalPost (now PRI) and as a reporter and assignment editor at the Cambodia Daily in Phnom Penh. She is a native of Southern California and a graduate of Stanford University.

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Does the human being have a free will? [A final essay I'm writing for a college class, please comment and critique]

**This is a first draft, the final paper is due monday. It's the first philosophy class I've taken, and I thought you all might have some critique or ideas that could help make it better. **

Does the human being have a free will?

Within the boundaries set by this essay, I am to explain that a free will does not exist. I will provide the basic and most comprehendible reasoning for the non existence of free will, and by extension the non existence of the soul.

Just like in the argument against the existence of a god, a tea pot flying around in space, or a flying spaghetti monster, it is not this essay’s purpose to disprove the existence of anything, but to refute any reason one might have to believe in the existence of a that thing. In this case, it is this essay’s purpose to convince you, the reader, of the non existence of a free will.

First, it must asked where this concept of a free will exists. Why do we as humans seem to believe that we have the ability to freely make choices independent of anything but our own “selves”? To put the question more simply; if free will does not exists, why does it appear to us like it does? The idea of a free will has two parts, the will, which refers to the ability to make conscious choice, and the free, which is a bit harder to define. I’m not here to disagree that we make choices, or that the choices we make are not our own, but those of someone else.

We certainly have a will, we do as humans make choices, we do. Similar to what the Baron Paul Heri D’Holbach said in his article on free will [1], as humans, the decisions we make are computed by our brains; electrical connections in our frontal lobes, made to take into consideration our environments, thoughts, and experiences up until the point of that decision in our lives. This begs the question though; where does free come in? Certainly our brains think, and make decisions, but what exactly about that is freely done? Not one thing about the choices we make is done randomly, every time our brain signals for something to happen, it is based upon predicted results, immediate, or far into the future, that the human thinks will be beneficial toward living or procreation in some way. This will is not free because, like our perception of the mind, it is based upon two things: a human’s genetic make-up, and the environment surrounding the human.

Simply put, the human does make choices, but these choices are nothing more than the simple calculations of the brain; machine built through trial and error conducted by genetic mutations in the form of evolution over a vast number of years. Because these computations are so complex and often use parts of brain which our consciousness is not connected to, and because our consciousness is only a small portion of our brains, our consciousness has a lack of reason for this calculation. Our brains have evolved to generalize that a lack of information is a bad thing. When we don’t understand something, often times our brains pretend that we do by making up information [2]. Our brain is constantly faking information and passing it around, giving our conscious mind a sense of completeness in the understanding of it’s surroundings, when in actuality much of it is just a virtual reality created by our brains; a patchwork of our real perception. Our free will is just another example of this patchwork, a simulation created by the brain, and perceived by our consciousness as reality, just to smooth out the internal processes of the supercomputer that is the brain.

Now that we’ve established that there is no reason to believe a free will exists, and that choice means nothing more than calculation based upon genetic makeup and environment, we consider the implications of the idea that a free will does not exist. If the free will of humans does not exist, than how does the world around us exist? Our environment has to be the result of something, and the act of an original creation must in some way be the result of the free will of something, unless we are to assume that everything has always existed*. That something, the first something which resulted in us, our conscious mind, and everything which we perceive and do not perceive, must at it’s very root have free will, be it random or conscious.

So, in conclusion, while we do not individually as humans have free will, we as humans are in some way the result of free will. While we’re not exactly sure what it is that does have free will, this free will in some way must exist in all it’s complete and chaotic randomness, and we as humans are a reflection of that. Our existence could be considered free will, or it could be considered a reflection of free will, and therefore whether the human has free will is all a question of semantics. Semantics aside, the human being is however, a result of free will.

*This, so far as I’m concerned is a viable secondary viewpoint.

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If free will is an illusion, responsibility is too

Human actions are determined.

Lawrence Harvey

Figures like Sam Harris and most recently Robert Sapolsky argue free will is an illusion. Yet most attempt to save the idea that we are morally responsible for our actions, in spite of this lack of free will to choose those actions or the freedom to have acted differently. Lawrence Harvey, grappling with the thought of Paul Rée, a thinker celebrated by the philosopher Friedrich Nietzsche, writes that if we are to believe free will is an illusion, the idea of responsibility must be thrown away with it.

Sam Harris will be appearing via Zoom, alongside over a hundred other leading thinkers and guests appearing in person such as Roger Penrose, Sabine Hossenfelder, Sadiq Khan and more, at the HowTheLightGetsIn festival this September. Talks, debates, music, and comedy, exploring the topics you find on the IAI. Book your place now.  

“Responsibility is a chimera which stalks the conscience of those

who are not bold enough to apply the deterministic laws of nature

to themselves…”

In 1878, Nietzsche wrote a letter to Paul Rée (1849–1901) in which he declared: ‘All my friends are now agreed that my book [ Human, All-Too-Human ] comes from and is written by you: so I congratulate you on this new authorship … Long live Réealism and my good friend!’ Although this friendship was not to last, many commentators agree that Rée had a profound, if temporary, influence on both Nietzsche’s thought and his method of philosophical expression. Arguably, this broad consensus gives weight to the idea that Rée helped to shape the course of modern continental philosophy, albeit from the intellectual sidelines.

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