Free Will and the Brain

Tyler and I have been arguing about free will for decades. One of the strongest arguments against free-will is an empirical argument due to physiologist Benjamin Libet. Libet famously found that the brain seems to signal a decision to act before the conscious mind makes an intention to act. Brain scans can see a finger tap coming 500 ms before the tap but the conscious decision seems to be made nly 150 ms before the tap. Libet’s results, however, are now being reinterpreted:

The Atlantic: 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.

…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.

The Atlantic piece with more background is here. A scientific piece summarizing some of the new experiments is here. Of course, the philosophical puzzles remain. Tyler and I will continue to argue.


“ I made my daily climb this morning up the wooded mountain trail near my home, I was not constantly issuing conscious instructions to the muscles, sinews, nerves, and organs of my body, or telling my body how to react to stones unexpectedly slipping underfoot or to the prick of the unseen thorn that drew blood from the back of my hand. Clearly my conscious mind would not know how to command such things. If free will is the issue, the pertinent question is whether going for that walk up that trail— conceiving of it, choosing to do it, persisting in doing it, for reasons (that is, final causes) of which I had some intentional grasp— was a rationally free activity, integrated within a larger intentionality directed toward some end. And the answer does not depend upon whether the individual physiological constituents of the experience were directly determined by a wholly conscious controller incorporeally residing in, say, my pineal gland.

“...There is simply something banal in trying to extricate a single moment of physiological activity from that totality and thereby prove anything about the rational liberty of the mind. More to the point, if the very same experiment had been undertaken from an entirely different conceptual vantage, the results might just as easily have been taken as triumphant proof of the reality of free will.

How amazing, the researchers might have concluded, that a person has the rational power to command his or her body to behave spontaneously at a future date—” I shall let the promptings of physiological impulse pass through my nerves like breezes through the strings of an Aeolian harp”— and then bring it to pass. The mind, it turns out, is so potent that it can even ordain the responsive quiescence of the flesh. There could scarcely be a more glorious vindication of the truth of rational freedom. Nor, for that matter, could there be a better illustration of the power of a final cause to bring about physical effects: the movement of the subject’s wrist occurred within a continuous activity directed toward a rational end consciously sought, apart from which it would not have happened at all; the whole structure of the act was teleological, which is precisely how a mechanistic view of reality says physical reality cannot behave.”

The Internet reveals that this is from,+which+is+precisely+how+a+mechanistic+view+of+reality+says+physical+reality+cannot+behave.&source=bl&ots=UeWq7MBwNb&sig=ACfU3U1w6NBO-ALGl6X6NvmWnCuJhnLB7Q&hl=fr&sa=X&ved=2ahUKEwjF_7rb4M3kAhUttlkKHbBkBLcQ6AEwAHoECAkQAQ#v=onepage&q=he%20whole%20structure%20of%20the%20act%20was%20teleological%2C%20which%20is%20precisely%20how%20a%20mechanistic%20view%20of%20reality%20says%20physical%20reality%20cannot%20behave.&f=false

Daniel Dennett's work explains everything intersting worth explaining about this issue. There are flaws in his position but they are boring definitional flaws, i.e., they are just about what most people think they are claiming when they say they have free will. In fact, the whole thing perfectly mirrors the consciousness debate: Dennett answers all the interesting questions, the rest is arguing over the meaning of a folk concept. As with Von Neumann's analogy: can a submarine swim? Sort of, maybe, who cares, swimming is not a scientific concept. It also the kind of attribute that we feel defines our human exceptionalism, which is maybe why we don't care. Perhaps there are schools of fish-philosophers debating whether it might be possible for an artificial fish to swim, or would they be zombie-fish?

The most interesting comment of Dennett's in regards to the Libet experiment is that a conscious intention must have some antecedent in the brain if we accept the we live in a causal universe. To the extent that the Libet experiment is surprising, it can only be that 500 ms is longer than what we would a priori expect.

Without free will, we are responsible for nothing and deserve credit for nothing. I'm reminded of the book Cowen recently mentioned in which the author makes the case for universal salvation (Cowen seemed to indicate his disagreement), a case made by several church fathers. According to the church fathers, all of us had preexisting souls and were faithful to God. It's only when the souls were brought into the material world that that they became sinners. It's not their fault, it's the circumstances of the material world. It's not clear to me if the existence of free will or the absence of free will caused sin in the material world: if the souls had free will, wouldn't they choose to be faithful to God, or is it because the souls lacked free will that they did not, could not, make the choice to be faithful. Universal salvation would seem to be dependent on the latter.

In the law, the inability to distinguish right from wrong separates the guilty from the innocent. Do mass killers have free will? Not if they cannot distinguish right from wrong. But in the law the issue is always considered in the context of a mental defect, the assumption being that choosing wrong is evidence of a mental defect and the absence of free will. From a religious perspective, those who cannot distinguish right from wrong are possessed by the devil: they don't have a mental defect, they are possessed. Many of the miracles performed by Jesus in the Gospels were on those possessed by demons (i.e., the devil), who lacked free will because they were possessed.

All of us experience free will: when confronted with two choices, one of which we know is wrong, but we cannot help ourselves. Is that free will or the absence of free will, the material world high-jacking the right choice our souls would otherwise make.

Good comment

Which church fathers?

I suggest that as an empirical rule any argument based on the authority of the church fathers is almost always vacuous.

First of all, the church fathers were quite mixed in their understanding of free will... because it’s not black and white. It’s not fair to say, however, that the church fathers as a group believed in universal salvation (which as ray ward points out... is a relevant question given mortal sin requires: a grave matter, full knowledge, and full consent. Without free will, full consent is not present and ones culpability is reduced to a point at which universal salvation might be quite likely).

To deariems comment tho... you real issue isn’t with the church fathers, it’s an appeal to divine revelation, which you reject at the outset and so find all arguments based on it unconvincing.

Even if one takes such a position, one should still read the church fathers (and actually many of our Christian ancestors) anyways. For example, there are many good comments below. Take a look. However, they are basically just repeating arguments already made by people like Augustine and Aquinas. Take a look at Aquinas in the first part, question 83...

If man doesn’t have free will, then there is no sense in making rules at all because without free will, no one can respond to the rational incentives to begin with. The very existence of rules in human society render free will a must. He also (including in other related articles) addresses inanimate matter and brute animals (natural instinct) concluding that man is different due to its rational nature... tho there are exceptions (habits or inanimate tendencies for example). What he is getting at is the mixed nature of instinct and rational cognitive action, of which humans solely posses among the natural world.

So yes, we ought read the fathers even if one competes rejects divine revelation.

“I answer that, Man has free-will: otherwise counsels, exhortations, commands, prohibitions, rewards, and punishments would be in vain. In order to make this evident, we must observe that some things act without judgment; as a stone moves downwards; and in like manner all things which lack knowledge. And some act from judgment, but not a free judgment; as brute animals. For the sheep, seeing the wolf, judges it a thing to be shunned, from a natural and not a free judgment, because it judges, not from reason, but from natural instinct. And the same thing is to be said of any judgment of brute animals. But man acts from judgment, because by his apprehensive power he judges that something should be avoided or sought. But because this judgment, in the case of some particular act, is not from a natural instinct, but from some act of comparison in the reason, therefore he acts from free judgment and retains the power of being inclined to various things. For reason in contingent matters may follow opposite courses, as we see in dialectic syllogisms and rhetorical arguments. Now particular operations are contingent, and therefore in such matters the judgment of reason may follow opposite courses, and is not determinate to one. And forasmuch as man is rational is it necessary that man have a free-will.”

One more general comment. The study in question is irrelevant to all of this. The well reasoned arguments do not deny the existence of instinct in human beings so who cares whether humans tap their fingers via instinct or reason. No one thinks about their heart beating either. People do rationally reflect on things like whether or not to have an affair even if variations in tendency (habits and vices) exist in such matters.

From the Christian POV... this is why the concept of culpability has been such a prominent matter to consider.

I suggest that as an empirical rule any argument based on the authority of the church fathers is almost always vacuous.

When have you made a non-vacuous remark in your years participating here?

I think Origen argued for universal salvation, even of the devil, but its debatable if he's a church father.

Free will leads to black and white questions for crime and punishment.

Diminished capacity is a bit more gray, and IMO not well addressed in our system of crime and punishment. At my first guess, essentially everyone in prison is of diminished capacity, and either punishing them and rehabilitating them won't change that. They need easier life paths with less challenges.

But America might have too fundamental a view of good and evil to approach that.

I should clarify. I think most criminals are of diminished capacity relative to the median, and we are all of diminished capacity relative to some platonic ideal of free will or consciousness.

I disagree. Free will is irrelevant to crime and punishment.

The only thing that matters is whether people respond to incentives. A legally mentally insane person is not held accountable for precisely this reason. They cannot follow incentives because they are incapable of knowing their actions are “wrong.”

The overwhelming percentage of prisoners do not belong in this category. They may be on the left side of the bell curve, but they know their actions were illegal. And they know that is why they are in prison.

I can kind of see that, and that I was addressing it first as a fairness issue. That is, if they are of diminished capacity should we really expect completely rational behavior?

But that's really how the two questions tie together. What if a belief in incentives demands too high a belief in rational capacity?

The old gag is that robbers have to be dumb enough to think they'll get away with it.

I should clarify that I would not abandon punishment, but I think we probably should pair it with more post-prison support.

The status quo that you're out, but you can't get a job because you have a criminal record, is not terribly productive.

Make government employer of last resort, at minimum wage minus .50

Is a dog rational? They can follow incentives.

Prisoners are humans. What does diminished capacity mean in this context? They’re dumber than animals ? No. That’s not a reasonable conclusion to draw. Having an IQ of 85 and a short term time preference might make someone more likely to commit crimes, but that is not a reasonable standard of ‘diminished capacity.’ You’re unintentionally classifying huge swaths of humanity as not having the reasoning ability of a chihuahua. Not to mention over half of the million or so yearly immigrants from Central America.

Agree on the need for reform post release. At minimum halfway houses should be obligatory and job assistance should be implemented.

Having the US government as the main employer of ex prisoners would be an ethical disaster and create terrible political incentives. So no.

Having government as the ___ of last resort solves all kinds of problems. And as long as it really is positioned as last resort, moral hazard is limited.

Not to say every criminal would take it, but bed and board has to reduce crime and homelessness at the margin.

Words fail me.

With a stroke of a pen you would create a giant moral hazard and add unfireable millions to a permanent government class. Within a year they would be paid minimum wage, within 5 years they would be on the regular GS scale for federal workers.

More make-work jobs for the bureaucracy is the last thing this country needs more of.

It’s a UBI but with none of the positives and all of the negatives.

A UBI encourages slacking, and under-employment.

A "last resort" at minimum wage minus .50 says you want to work, you've tried everywhere else, and this is the best you can do.

If it pulls slackers off couches, that's the opposite of moral hazard. That's moral incentive.

You seem eternally baffled by how incentives work.

Creating millions of no-show unfireable federal government positions is about the dumbest thing you've said in a while.

When your argument depends on stuff I never said ("no-show unfireable federal government positions") ..

"Make government employer of last resort, at minimum wage minus .50"

What makes you think criminals would show up for work to a job that pays minimum wage minus $0.50 to an extent that it would reduce the crime rate?

The reformed/better controlled individuals would get better jobs, the non-reformed would go back to crime because the hourly pay is much better and the poor impulse control individuals would continue to have poor impulse control.

"Tyler and I have been arguing about free will for decades. "

well, that seems a rather minor philosophical issue for a couple of PhD's to focus upon at such length.

Many much bigger metaphysical issues must be resolved before one gets down to free-will.

You do not "know" that you even have a "Brain".
You do not know that your perceived reality exists at all.

The list of things that you do KNOW with absolute certainty is an extremely short, one item list.

"You do not "know" that you even have a "Brain"."

You are correct that Alex (and Tyler) don't know for sure that they have brains, although I'm pretty sure they do. However, the economist they sometimes have lunch with and have likely discussed free will with, Robin Hanson, has posted his GRE scores on his home page. You simply can't score that high without a brain.

'The list of things that you do KNOW with absolute certainty is an extremely short, one item list.'

Kant would disagree, at mind numbing length.

But then, who really knows Kant, right?

Comments without Kant are empty, insights without Kant are blind?

I'm pretty sure Tyler doesn't mean they've been arguing this point for decades continuously, but that it's an off-and-on argument.

Also hardly seems like a minor philosophical point, it's one that philosophers have returned to again and again throughout history.

This is actually a quite interesting comment. There is a difference, often elided, between sensation and free will.
Sensation seems to be a fundamental property in the sense that it is not explainable (currently) by any known physical theory - you can't derive it from the known properties of atoms, for example. And the proof of the existence of sensation is fundamental - we sense things. At least I do. Even if we are brains in a vat and all our senses are lying to us, there is some notion of 'us' that is sensing those lies.

Free will is not the same thing. It implies that the entity that senses can choose, and that the choice is not deterministic. It's a harder argument to make.

My personal belief is that most people - including most scientists - conflate randomness with meaninglessness and do this because they don't bother to distinguish between randomness and non-determinism from the point of view of an observer with finite computational ability. I know that sounds crazy to most people.

Oh, and that something that looks random (e.g., quantum processes acting on neurons) can actually be meaningful. Thus, quantum processes allow for meaningful decisions even if quantum mechanics is stochastic.
See, crazy.

Are you saying individuals don't have free-will, like Trump?

Or are you saying groups of individuals don't have free-will, like the Trump Administration?

If groups don't have free-will, wouldn't we want to limit government and have more individual liberty?

Free clothing; free college; free food; free health; free housing for economic migrants/illegal aliens; free everything but there is no free will.

Meanwhile democrats promise to take away our gas cars and stoves, our private healthcare, our affordable gas and electricity, our tax cuts, and our jobs.

Seriously, free will requires a well-formed conscience.

Pretty sure one doesn't have a well-formed conscience if one believes that abortion (murder) is health care or that there are 15 genders.

You also don’t have a conscience if you believe its ok to eat animals (murder) or you believe humanity originated in a magical garden with a talking snake. See how easy it is to play that game?

See how easy it is to play that game?

No clue why you're so solicitous of animal life and not plant life.

I'm not a vegetarian because I love animals...I'm a vegetarian because I HATE PLANTS!

Don’t be ridiculous. I have a conscience AND I know eating animals is cruel* but I also have free will and so I choose to eat animals because I deem my desire to enjoy delicious protein to outweigh my sense that animals are being deprived of something when I kill them (deprived not of conscience or consciousness perhaps but deprived of awareness/sentience).

*better still: alleged to cruel by many, including smart and moral people.

I eat animals because I am an omnivore and, prepared correctly, some animals are delicious.

I don't eat frogs, slugs, snails, turtles, squirrels, bunnies, or Robin's but I looooovvve chicken.

Bunnies are cute but cows annoy me - always looking at me with that vacuous expression.

"What the f*ck you lookin' at", I ask but they don't say nothing. They just stare.

Fire up the BBQ! Let's burn some flesh! 🔥😈🔥

This comments section is bound to go the same way as every comments section under every blog post that ever mentions "free will." Well, here's a piece of information that seldom makes it into the comments:

The Free Will Theorem

Don't just learn about the theorem, though. Think about it's implications for human decision-making at the neurological level. That's free will.

Thanks for this.

(For what it's worth, I think the argument you link to is a worthwhile approach but this is still funny)

Debates about free will are always really about whether the debaters view humans as useless sheep that need elite guidance, or not.

Since you and Tyler are in lockstep agreeement on that, I really doubt you have much to debate.


Unless you are one of those people who believes they are in telepathic communication with a supreme being, then we are constrained by the laws of nature.

The laws of nature provide for determinism and random effects via quantum mechanics. Neither determinism or random effects is free will.

Knock yourself out, pal. I know you can’t help yourself.

I guess that's the modern non-religious argument. "It's my brain, but I'm not responsible, because the part making decisions isn't 'me'"

Of course it's you.

All the cool philosophers know compatibilism is the answer. This whole "determinism defeats free will" is smuggled in as a free assumption but isn't even logically coherent.


Looks legit.

How odd. I'm a casual observer, but this seems a strange framing. I was never that into religious arguments about free will, but in the context of God, omniscience and predestination it made a bit of sense.

But in the domain of neuroscience, why bother?

If the brain is the mind then consciousness is an interesting question, but free will is solved.

I don't really understand the line about how in Schurger's experiment "they included a control condition in which people didn’t move at all".

The ML classifier is probably no smarter than a human. So if we ourselves can only tell that we are going to take an action 150ms before it’s not surprising that the classifier finds the same thing. But that doesn’t mean that the information to predict that action didn’t exist before. Perhaps a superintelligence could have predicted it much earlier.

--so is "cognition" actually an expression of "voluntarism"?

Neuroscience may yet tell us something informative about brain physiology without quite accounting for free or constrained exercises of volition, itself possibly the "deep source" of cognition and even more poorly understood than human understandings of human brains.

We are all just puppets of the global microbial hive mind. They control our subconscious impulses through our intestinal flora.

Mixed into the flow of nutrients released during the process of digestion, there are substances that affect us in a Cordyceps-like manner. It is hard to isolate this effect from our own indigenous secretions, however, because there is no control group. We are so dependent on our gut bacteria that we can't really survive properly without them.

The ancient Greeks spoke of "muses": flashes of creativity, original thought, and inspiration were believed to have an external source. They weren't wrong.

As a former phil grad student, my impression is that basically no academic philosopher thinks that Libet experiments are strong evidence against the possession of free will (libertarian or not).

Exactly! Libet's experiment was never any reason to weaken belief in free will. That's just 'consciousness prejudice', just like the idea that you need to be consciously aware of a decision in order for it to be rational. That's ludicrous! The unconsciousness quite obviously takes a lot of rational, and possibly free, decisions. That you are regularly only consciously aware of them after the fact doesn't make them less rational or free.

Why don’t you make a video summarising the debate between you and Tyler on free will, something similar to the rent vs buy a house one? It would be very interesting to know the arguments of both of you!

Much better comments, good work cleaning things up. +5 internet points to all participants, except Transnational Pants Machine. He's still in violation.

Does he have to sit in the penalty box?

If there's no free will, what are we going to do about it?

We will do what we must. We have no choice.

A) Is an argument about the existence of free will any different than an argument about the existence of the soul? B) I find the arguments that the rules we enforce can't function without this concept silly. C) I'd guess we can base our Justice System on better (and more rational) fundamentals. D) Given that the vast majority of adults believe in the supernatural, perhaps we should pretend that free will is a real thing. and bonus points E) Do you think AT and TC also argue whether numbers actually exist?

I'm a big fan of David Deutsch and find his ideas about free will agreeable. On a supreme being, I still agree with Raymond Smullyan's Who Knows?

Gag me with a spoon.

Thanks Alex, really interesting!

Free will debates might be too suffused with unknowable metaphysical and theological biases/thinking to be of use. Maybe a better approach is to focus on agency: what actions can we be responsible for, and how many?

Could we — in a situation where we have to choose — have “done otherwise“?

Take the funny Florida Man memes presented every week or so online. Today there was a story of two 20 year old African American dudes who were so unhappy at being served allegedly cold burgers at McDonald’s that they pulled out a gun to, uh, signal the seriousness of their dissatisfaction. Alas for them after brandishing their weapon(s) they hung around wait for warmer burgers.

My point is, surely they had the agency to NOT pull a gun, and the agency to you know realize that was an overreaction and finally the agency to realize that the police would eventually be summoned. Would anyone say “well, they weren’t acting as agents and thus cannot be held responsible“? And if someone would say that, at what point would they say these dudes were not agents?

I think what people are getting at by “free will” describes actions that can be affected by higher facilities, such as morality and and abstract reasoning. Even if those higher facilities are mechanistic and maybe even deterministic in their inner workings. Basically, the things that are driven by thought and internal debate. I have no trouble saying that certain robot systems have free will, they just aren’t all that smart.

As Wittgenstein might say (I emphasize might), the problem is a pseudo-problem. The real problem is what to do with people who do things we don't want them to do (Free will, so-called, being related to questions of culpability, and responsiveness to correction, ascription of responsibilies and rights, and so on.)
I'm not saying this isn't obvious.

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