A handful of musings about free will have been popping up in my blog reader of late. Jerry Coyne has been discussing the issue with Eric MacDonald in a series of posts (further links therein). Russell Blackford writes a long post that he promises isn’t the post he will eventually write, David Eagleman has an article in the Atlantic, and Zach Weiner also chimes in. So we have a biologist studying theology, an ex-Anglican priest turned agnostic, a philosopher and neuroscientist both of whom write science fiction, and a webcartoonist studying physics. That constitutes a reasonable spectrum of opinion. Still, what discussion of reality is complete without a cosmologist chiming in?
In some ways, asking whether free will exists is a lot like asking whether time really exists. In both cases, it’s different from asking “do unicorns exist?” or “does dark matter exist?” In these examples, we are pretty clear on what the concepts are supposed to denote, and what it would mean for them to actually exist; what’s left is a matter of collecting evidence and judging its value. I take it that this is not what we mean when we ask about the existence of free will.
It’s possible to deny the existence of something while using it all the time. Julian Barbour doesn’t believe time is real, but he is perfectly capable of showing up to a meeting on time. Likewise, people who question the existence of free will don’t have any trouble making choices. (John Searle has joked that people who deny free will, when ordering at a restaurant, should say “just bring me whatever the laws of nature have determined I will get.”) Whatever it is we are asking, it’s not simply a matter of evidence.
When people make use of a concept and simultaneously deny its existence, what they typically mean is that the concept in question is nowhere to be found in some “fundamental” description of reality. Julian Barbour thinks that if we just understood the laws of physics better, “time” would disappear from our vocabulary. Likewise, discussions about the existence of free will often center on whether we really need to include such freedom as an irreducible component of reality, without which our understanding would be fundamentally incomplete.
There are people who do believe in free will in this sense; that we need to invoke a notion of free will as an essential ingredient in reality, over and above the conventional laws of nature. These are libertarians, in the metaphysical sense rather than the political-philosophy sense. They may explicitly believe that conscious creatures are governed by a blob of spirit energy that transcends materialist categories, or they can be more vague about how the free will actually manifests itself. But in either event, they believe that our freedom of choice cannot be reduced to our constituent particles evolving according to the laws of physics.
This version of free will, as anyone who reads the blog will recognize, I don’t buy at all. Within the regime of everyday life, the underlying laws of physics are completely understood. There’s a lot we don’t understand about consciousness, but none of the problems we face rise to the level that we should be tempted to distrust our basic understanding of how the atoms and forces inside our brains work. Note that it’s not really a matter of “determinism”; it’s simply a question of whether there are impersonal laws of nature at all. The fact that quantum mechanics introduces a stochastic component into physical predictions doesn’t open the door for true libertarian free will.
But I also don’t think that “playing a necessary role in every effective description of the world” is a very good way of defining “existence” or “reality.” If there is anything that modern physics has taught us, it’s that it’s very often possible to discuss a single situation in two or more completely different (but equivalent) ways. Duality in particle physics is probably the most carefully-defined example, but the same idea holds in more familiar contexts. When we talk about air in a room, we can describe it by listing the properties of each and every molecule, or we speak in coarse-grained terms about things like temperature and pressure. One description is more “fundamental,” in that its regime of validity is wider; but both have a regime of validity, and as long as we are in that regime, the relevant concepts have a perfectly good claim to “existing.” It would be silly to say that temperature isn’t “real,” just because the concept doesn’t appear in some fine-grained vocabulary.
We talk about the world using different levels of description, appropriate to the question of interest. Some levels might be thought of as “fundamental” and others as “emergent,” but they are all there. Does baseball exist? It’s nowhere to be found in the Standard Model of particle physics. But any definition of “exist” that can’t find room for baseball seems overly narrow to me. It’s true that we could take any particular example of a baseball game and choose to describe it by listing the exact quantum state of each elementary particle contained in the players and the bat and ball and the field etc. But why in the world would anyone think that is a good idea? The concept of baseball is emergent rather than fundamental, but it’s no less real for all of that.
Likewise for free will. We can be perfectly orthodox materialists and yet believe in free will, if what we mean by that is that there is a level of description that is useful in certain contexts and that includes “autonomous agents with free will” as crucial ingredients. That’s the “variety of free will worth having,” as Daniel Dennett would put it.
I’m not saying anything original — this is a well-known position, probably the majority view among contemporary philosophers. It’s a school of thought called compatibilism: see Wikipedia, or (better) the Stanford Encyclopedia of Philosophy. Free will as an emergent phenomenon can be perfectly compatible with an underlying materialist view of the world.
Of course, just because it can be compatible with the laws of nature, doesn’t mean that the concept of free will actually is the best way to talk about emergent human behaviors. (Just because I know the rules of chess doesn’t make me a grandmaster.) There are still plenty of interesting questions remaining to be clarified. At the very least, there is some kind of tension between a microscopic view in which we’re just made of particles and a macroscopic one in which we have “choices.” David Albert does a great job of articulating this tension in this short excerpt from a Bloggingheads dialogue we did some time back.
I don’t generally think that the superior wisdom one acquires via training as a physicist grants one the power to see clearly through complicated issues and make philosophical conundrums dissolve away. But this is a case where insights from physics might actually be useful. In particular, what we are faced with is the task of reconciling effective theories at different levels of description that have apparently incompatible features: the impersonal evolution of the microscopic level (whether we go all the way to atoms, or stick with genes and neurons) and the irreducible possibility of “choice” at the macroscopic level.
This kind of tension also appears in physics. Indeed, the arrow of time is a great example. The microscopic laws of physics (as far as we know) are perfectly reversible; evolution forward in time is no different from evolution backward in time. But the macroscopic world is manifestly characterized by irreversibility. That doesn’t mean that the two descriptions are incompatible, just that we have to be careful about how they fit together. In the case of irreversibility, we realize that we need an extra ingredient: the particular configuration of our universe, not just the laws of physics.
In fact, the connection goes beyond a mere analogy. If you look up arguments against compatibilism, you find something called The Consequence Argument. This is based on the “fundamental difference between the past and future” — what we do now affects the future, but it doesn’t affect the past. Earlier times are fixed, while we can still influence later times. The consequence argument points out that deterministic laws imply that the future isn’t really up for grabs; it’s determined by the present state just as surely as the past is. So we don’t really have choices about anything. (For purposes of this discussion we can ignore the question of whether the microscopic laws really are deterministic; all that really matters are that there are laws.)
The problem with this is that it mixes levels of description. If we know the exact quantum state of all of our atoms and forces, in principle Laplace’s Demon can predict our future. But we don’t know that, and we never will, and therefore who cares? What we are trying to do is to construct an effective understanding of human beings, not of electrons and nuclei. Given our lack of complete microscopic information, the question we should be asking is, “does the best theory of human beings include an element of free choice?” The reason why it might is precisely because we have different epistemic access to the past and the future. The low entropy of the past allows for the existence of “records” and “memories,” and consequently forces us to model the past as “settled.” We have no such restriction toward the future, which is why we model the future as something we can influence. From this perspective, free will is no more ruled out by the consequence argument than the Second Law of Thermodynamics is ruled out by microscopic reversibility.
None of this quite settles the question of whether “free will” is actually a crucial ingredient in the best theory of human beings we can imagine developing. I suspect it is, but I’m willing to change my mind as we learn more. The context in which it really matters is when we turn to questions of moral responsibility. Should we hold people who do bad things responsible for their actions — even if our understanding of neuroscience improves to such an extent that we can identify precisely which gene or neuron “made them do it?” (This is the focus of Eagleman’s article.)
This is a resolutely practical question — who gets thrown in jail? Criminal law has the concept of mens rea, guilty mind. We don’t find people guilty of crimes simply because they committed them; they had to be responsible, in the sense that they had the mental capacity to have known better. In other words: we have a model of human beings as rational agents, able to gather and process information, understand consequences, and make decisions. When they make the wrong ones, they deserve to be punished. People who are incapable of this kind of rationality — young children, the mentally ill — are not held responsible in the same way.
Might we someday understand the brain so well, reducing thought to a series of mechanical processes, that this model ceases to be useful? It seems possible, but unlikely. We know that air is made of molecules, but the laws of thermodynamics haven’t lost their usefulness. Thinking of the collections of atoms we call “people” as rational agents capable of making choices seems like a pretty good theory to me, likely to remain useful for a long while to come. At least, that’s what I choose to think.
“Free will” is a polysemic term that covers two different issues: causal determinism, and moral responsibility. All our actions may be (and probably are) causally determined), and yet we may still be free in the moral sense. I take free will to be agency that is not coerced; hence whether or not agency is causally determined, we are free to act (according to our “natures” if you like) when we are not unjustifiably coerced in our choices. I discuss this here.
Perhaps the great paradox of our lives is that free will is fundamentally an illusion but we have to live as though it is real.
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@Alex R.
Because I (and I’m pretty sure Sean) completely disagree with you that the concept of a god is useful in describing anything, at any level. Thermodynamics is wonderfully predictive and explains a lot, using temperature, pressure, etc., within a certain physical regime. The god theory predicts… nothing, at least nothing you can get religious people to agree on. (There’s no equivalent of PV=NkT in religion – at all.) The theory of god has no explanatory power. In any regime.
Free will is like temperature in that it’s a very useful concept, and it certainly appears to exist according to everyday definitions of it. God isn’t useful, and doesn’t appear to exist, at a fundamental or emergent level.
it is fine to talk of free will as an emergent, or even convergent result, yet if that result is an illusion, then we still can’t call it real. I would say that Free-will is less like a basebal and more like a mirage in the dessert. It is as real to us as water when we see it, but when we get up close it disappears.
Sean claims physics at the medium-size level is completely understood, But can Sean come up with a convincing narrative concerning what happens during a measurement? When he does so, then I’ll pay attention to what he as a physicist has to say about free will.
to stick with sports balls as a metaphor, my father is an inventor (myself a material scientist as well), and in the 1970’s he invented a croquet ball made of polyurethane. The idea was it for it to behave like a wood ball. The real baseball Sean talks about is a bit like this plastic croquet ball to me. it may work like a real wood ball, but when you look at it it is clear that it is indeed plastic. The baseball of free-will is a different product, or to be ungenerous, a fake.
Sean writes:
“Thinking of the collections of atoms we call ‘people’ as rational agents capable of making choices seems like a pretty good theory to me, likely to remain useful for a long while to come.”
Yes, it will always be useful, and true, because there’s no conflict between being a fully deterministic system whose future is fixed, sitting out there in the 4D block universe, and making choices and having control, http://www.naturalism.org/spacetime.htm Choice-making in light of reasons is just as real a causal process as anything else in nature, so will remain an essential ingredient of how we explain behavior at the level of intentional action.
However, to call this “free will” is problematic given the long-standing libertarian connotation that the will is somehow free from causation. Better to call it free action, freedom, or free choice, where the freedom in question is that of not being coerced or constrained by agents or circumstances that block one’s desired course of action. Such freedom, very much worth wanting, is perfectly compatible with the deterministic evolution of behavior in accordance with whatever laws govern it, at whatever level.
But seeing that we don’t have contra-causal, libertarian free will, that we could *not* have done otherwise in actual situations as they played out (as opposed to counterfactual situations, see http://www.naturalism.org/choice_and_creativity.htm#chdo ), puts pressure on the traditional notion of desert-based retribution, hence has significant implications for our criminal justice system. David Eagleman makes this point in his Atlantic article and in his book Incognito. Sam Harris takes the same position in The Moral Landscape, discussed at http://www.naturalism.org/roundup.htm#Harris , as does biologist Anthony Cashmore for the National Academy of Sciences, http://www.naturalism.org/roundup.htm#cashmore . To the extent our beliefs, attitudes and practices related to responsibility, credit and blame are premised on the notion of contra-causal free will, they will all be affected as we naturalize our notions of freedom and human agency, http://www.naturalism.org/freewill.htm
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If free will is the ability to make choices, what shapes those choices? “Preferences”, the economists say… So where do preferences come from, and can you choose to change them? If you can’t simply choose a different set of preferences (and I submit that you cannot), then in what sense could your choices be said to be “free”? They are determined by your preferences, without any need to get down to the basic physics of the matter. If you present me with a menu with a choice of either steak or smoked halibut for the main course, I’ll choose the steak every single time – because I absolutely hate smoked halibut. Is that choice the result of a meaningful exercise of free will? Could I simply choose to like smoked halibut?
So you say Free Will is as real as Baseball. You failed to actually provide any useful definition of free will, though, so I have no idea what this post was about…
Is it free will to be able to choose between Mountain Dew and Pepsi? Or is it free will to decide which I will choose? I for one can’t decide what I choose when the options are so closely related. I can rationalize my choice (by e.g., reading the caffeine content, recognizing that I think one of the two taste better or just being willing to test one again [we don’t have Mountain Dew in Sweden :/ ]) but I can’t decide what I choose.
Lets simplify the problem I face between Pepsi and Mountain Dew down to taste. Is it free will to be able to choose between these soft drinks, or is it free will to decide which one I think taste better by your definition?
To me it seems that the first option isn’t really free will as factors, such as the taste, are beyond my realm of choice. The second option seems more like free will, but as far as I know, you cannot choose to like one taste over another… perhaps we can alter our sense of taste in the future, but for now I don’t think free will has emerged to the level of choosing which soft drink you like.
I think an important point (which you may have made and I overlooked) is the answer should depend on what question you are asking.
If you are asking in a very general, philosophical way, then the answer should be: ‘there are physical laws, these determine our choices, thus we have no free will’.
If the question you are asking is ‘does a model of the behavior of an individual or a group of people need to include free will to be accurate’, then, I think the answer is yes. But you could just as easily call it something else; stochastic behavior. Or something.
Calling it ‘free will’ just because we don’t understand the connection between the rules and the outcome seems disingenuous. Why do we need to call if ‘free will’? Why not just say people are unpredictable? We have trouble predicting weather, but we don’t claim that clouds have free will.
“There’s no free will,” says the philosopher;
“To hang is most unjust.”
“There is no free will,” assents the officer;
“We hang because we must.”
–Ambrose Bierce
Sean, I am surprised and puzzled that you would say “If we know the exact quantum state of all of our atoms and forces, in principle Laplace’s Demon can predict our future.” As you know, the particular outcomes of many quantum processes are uncaused. These outcomes have macroscopic consequences. I gave an example on Jerry Coyne’s site:
Suppose Schrodinger keeps lots of his cats in a small shielded room deep below the earth’s surface, and brings a gun triggered by a Geiger counter into the room. The Geiger counter is aimed at a weak radiation source, which triggers the Geiger counter once every few minutes. He comes back later (or sits and watches—this is not an observer effect) after hearing a bang, and finds one cat dead, and lots of live cats. We can indeed give good causal explanations at some level for why one of the cats died, but we cannot give a causal explanation for why that particular cat died and not one of the others.
This kind of uncaused event could also affect the human brain. Granted, this does not mean “free will” but only randomization. Still, the point is that Laplace’s Demon has been out of a job for almost a century. Don’t you agree?
HI Sean
You say : “There’s a lot we don’t understand about consciousness, but none of the problems we face rise to the level that we should be tempted to distrust our basic understanding of how the atoms and forces inside our brains work.” The fact that we do understand how atoms and forces work yet don’t understand how consciousness works should be of some concern as consciousness is the means by which we understand those forces and the workings of the atom. This is equivalent to using a tool without knowing what the tool is, and whether or not that tool alters the nature of the thing it interacts with. To a hammer, everything is nails. To consciousness everything is … what ? And how does that alter what might be there if we were not conscious of it in some way.
“To a hammer, everything is nails”
Yes, and deep inside a hammer everything is atoms and forces, but we have a pretty darn good idea how the thing works.
If one really believes that we have no sort of free will at all, then by the same token we should not worry about what consequences this has, for criminal justice or anything else—you are saying “what should we decide (about something specific) if we (i.e. everyone in society) can’t decide at all (in general)?” this is a self-contradictory question.
The idea that one should not be punished if one is not responsible, couldn’t have decided otherwise etc invalidates only some reasons for punishment, namely educating the convict to mend his ways and, perhaps, revenge (assuming one accepts that as a valid reason at all). It does not invalidate other reasons, such as protecting society from those proven dangerous and deterrence. The latter might seem a bit strange; after all, if someone could not have chosen otherwise, then how could he possibly be deterred? One has to see the whole system. For example, even allowing that, say, a rapist couldn’t have decided otherwise in a given context (say, a society in which rape is frowned upon but tolerated) does not imply that he would not decide otherwise in another context (say, in a society in which rape is strictly punished). Even if we are automatons with no free will at all, that doesn’t mean that information such as expected punishment etc doesn’t play a role in the “decision”.
Sean, can you elaborate on this statement you made: “the fact that quantum mechanics introduces a stochastic component into physical predictions doesn’t open the door for true libertarian free will.”
What I fail to see is how the stochastic nature of quantum mechanics doesn’t open the door to free will…? If Newtonian physics were the end all be all of physics then we could predict every event in the future and therefore all interactions would be predetermined and free will could not be true in the sense that all decisions were made before you were even born. However, with the stochastic nature of quantum mechanics and the uncertainty principle we are unable to predict anything with 100% certainty and therefore I perceive all our actions (or the actions of particles colliding) as reactions to the current environment rather than a single step in a predetermined chain of events. This leads me to believe that free can be considered true on almost all levels.
I understand that at the level of the brain and consciousness quantum mechanics doesn’t necessarily play a major role, though it does appear that many proteins and large molecules exhibit quantum behavior. Still, with the nature of quantum mechanics it will not be possible to accurately predict all thought processes perfectly because there will be some variation, even if only in the environment the person lives in.
I’m not a physicist nor a philosopher but I love discussing this topic. Thanks for this post Sean!
The problem with #43 is the assumption that since free will is the opposite of determinism, and the stochastic component of quantum mechanics is the opposite of determinism, then the stochastic component of quantum mechanics must imply free will. In other words, just because we can’t predict something even in principle doesn’t mean that it must be governed by free will, unless your definition of free will means that a decaying nucleus has it.
“just bring me whatever the laws of nature have determined I will get.” What if I have operant conditioning that produces a verbal report to the waiter “Bring me another cheese burger just like the cheeseburger I had yesterday”. Or I have operant conditioning that I must not eat at the same restaurant everyday. Or I never eat anything I have never eaten before by ‘force of habit”. At the very least, we mostly make predetermined choices. Paper or Plastic, black or with cream, whole wheat or white. Are these subject to agency and volition. Really?
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I found this quote from Popper to be an interesting take on the question of free will:
“New ideas have a striking similarity to genetic mutations. Now, let us look for a moment at genetic mutations. Mutations are, it seems, brought about by quantum theoretical indeterminacy (including radiation effects). Accordingly, they are also probabilistic and not in themselves originally selected or adequate, but on them there subsequently operates natural selection which eliminates inappropriate mutations. Now we could conceive of a similar process with respect to new ideas and to free-will decisions, and similar things. . . That is to say, a range of possibilities is brought about by a probabilistic and quantum mechanically characterized set of proposals, as it were – of possibilities brought forward by the brain. On these there then operates a kind of selective procedure which eliminates those proposals and those possibilities which are not acceptable to the mind.”
Sean
Since some of you readers grew up in “soccer” parts of the world you should be careful with using baseball as an example of something “real”.
Sean’s main point seems to be this:
“We can be perfectly orthodox materialists and yet believe in free will, if what we mean by that is that there is a level of description that is useful in certain contexts and that includes “autonomous agents with free will” as crucial ingredients.”
How is it useful to include that phrase? What would be lost from our model of the world if we omitted it? Nothing that I can see.
I’m neither denying nor assenting to the existence of “free will”. I think it’s too meaningless a term to be worth taking either position on.
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