Do humans have free will?

And the many worlds-interpretation is deterministic in exactly that sense: the wave function of the universe today is completely determined by the wave function of the universe at the beginning of the universe; in fact, it’s basically just a rotation of the latter through a high-dimensional, abstract space.

Saying this is simply wrong in many worlds. The wave function there evolves from a completely undecayed atom into a coherent superposition of decayed and undecayed states—which, again, is completely equivalent with regards to its information content to the wave function at any prior point.

What I’m saying is that I think you misunderstand what most people mean when they claim that they ‘could have done otherwise’. Again, of course, if you have them do everything in the same way as before, they will choose the same—but the potential of making a different choice is not touched by this, because to choose differently, you have to do something differently. Choice is an action; if you simply replay a sequence of actions, the outcome won’t be any more different than when you record it on film, and then replay the movie. Just because you can do so, because you can record me choosing something, and then replay the movie, and observe me choosing the same way again, simply has no impact on whether the choice was free.

It’s the same thing as with me ordering pizza yesterday: just because the fact of me making that order is fixed doesn’t mean that I didn’t order it freely. The same is true if you’ve recorded me placing that order on video: no matter how often you replay it, you won’t observe me placing a different order. And in the last consequence, this is also true if you just reset the universe to a point before I place my order, and observe me placing that same order again: I may do so, every time again, completely freely.

Although of course there’s a difficulty with the coherence of that last scenario: if you’d really reset the universe, you wouldn’t know anything about my order.

No, I think you misunderstand what most people mean. I think most people’s sense of “free will” entails an “agent”, a volitional “self” that somehow floats magically free of cause and effect, and that can “choose” differently (in some ill-defined way that is apparently neither deterministic nor random) in an exact re-run of the universe.

Cite: much of religion and our criminal justice system are based on this fundamentally mistaken and incoherent idea.

The model is actually incompatibilist, on most readings: it’s necessary that there are certain facts such that they aren’t fixed by the state of the universe at a given point in time. (Although I do realize that some might consider the model compatibilist simply based on the fact that a ‘replay’ results in the same outcomes.)

No, I claim that there’s nothing magical about ‘could have done otherwise’, and that an agent indeed could have done otherwise in my model, in every sense necessary to the notion of free will. Thus, I reject your claim that I’m merely playing with semantics (or, if I am, then all talk about concepts which have evolved under further scrutiny—such as atoms, genes, consciousness, particles, and basically everything we actually ever have studied—is just playing a semantic game).

But it isn’t the same as the word used in the discussion of free will. Nor is it the same as the word used in the colloquial discussion of, say, Schroedinger’s Cat. Either the cat lives or it dies, but which is not “determined” ahead of time.

From the point of view of a human, watching the atom – watching a whole bunch of atoms – the decay is random. You can’t predict which one is going to pop next. There is no evidence of “determination” in the sense that the atoms have little timers inside them, counting down to the moment they decay.

Since the discussion of free will is on a human level, we don’t get to view the wave-function of the multiverse. We can only try to figure out if our decision to break our diet and have Cheetos was made by ourselves, or by a string-pulling universe.

The quantum-mechanical definition of “determined” is different from the “it was fated to happen” definition.

Part of my disagreement is that I don’t believe we can “rewind the film” exactly. We can look back via memory to the way the situation was, but we cannot reconstruct it.

I agree that if we reconstructed the past exactly, right down to the precise electro-chemical state of every neuron in every brain of every person (and animal…and plant…) in the entire cosmos, then, yeah, decisions would likely come out the same way…for a while. It wouldn’t take long for them to diverge, however, and so events, after the first few (seconds? minutes? hours?) would, in fact, turn out differently.

I might still order pizza…but two hours later, I might…or might not…decline on a fifth slice.

(Ha! That’ll be the day!)

I’m not accusing you of playing a semantic game, just creating an unintentional semantic distraction. I think that you are objectively mistaken in your assumption of what is trivial and what is not to most of humanity. I think that the vast majority of humankind still believes in the kind of free will that you dismiss as trivially false in a couple of sentences before moving on to weightier matters.

If there’s divergence, the crucial question is why? If it’s attributable to random effects, then so what? That’s not “agency”, that’s not using “free will” to change anything. And if it’s not random effects, then what exactly do you think is going on that does not follow deterministic cause-and-effect to produce a different outcome?

Not to get too deeply into what we think that other people think, but I think that if you were to actually talk to people (as opposed to just basically calling them all morons), you’d see that what they want is a certain kind of self-determination; to be something other than just a leaf on the wind, merely along for the ride, an epiphenomenal observer without any real agency, just buffeted by unseen and incomprehensible forces of causality. And I think it’s astonishing that our universe, to the best of our current knowledge, actually allows for that.

Where’s the difference? The definition of ‘determinism’ at play in the MWI is the same as in Newtonian mechanics is the same that precludes any choice: because whatever happens, it was fated to happen from the beginning of the universe—there’s no ‘elbow room’, so to speak.

But that’s just because the point of view of the human observer is incomplete. They merely get to observe one branch of the wave function. If we imagine some sort of meta-observer that could ‘observe’ all branches simultaneously, there would be no randomness. But merely being ignorant of the full picture isn’t sufficient to salvage any sort of indeterminism—and if it were, you would not need quantum mechanics for it, because you have that same sort of ignorance in plain old Newtonian mechanics.

Again, in what way? In the MWI, everything that happens was ‘fated to happen’ in exactly the same way as in Newtonian mechanics.

See, the point is simply that I don’t dismiss it as false. I think there’s a very real and important sense in which agents ‘could have done otherwise’ in our actual universe; that sense might not be congruent with the naive idea of just repeating the same things once again, but it gives us everything that we originally wanted to have, that’s ultimately really relevant for having meaningful free will.

I agree that this is the kind of motivated reasoning that people have for their magical thinking about free will. Similarly, a vast number of people believe (and desperately want to believe) that they will meet Jesus in heaven when they die. Does that populist desire to believe carry similar weight for you?

Here we part company. I don’t think anything that you have described equates to that; and if your “reimagining” of free will allows people to maintain their misconceptions, it is likely to cause real-world social damage by inhibiting the much-needed reform of a criminal justice system that is based on those misconceptions.

In any event, I’m not in the least concerned about whether reality comports with what people want to believe. Far from treating people like “morons”, I think it would be extremely patronizing to suppose that people cannot cope with the existential implications of understanding how the universe really is.

Agreed; that’s one of the problems with this topic. There isn’t any experimental test we can apply to figure out if our human agency is a meaningful part of time-line divergence of this sort.

Ultimately, it’s a philosophical matter, not a scientific one. That’s one of the reasons these threads are so barren of meaningful conclusions. (“Is reality unitary, or plural?”)

I’m not aware that we are agreeing about anything here.

I said that there are deterministic processes and perhaps truly random processes, and that neither of these comport with the intuitive could-have-done-otherwise sense of free will.

Yet you claim (I think) that free will still exists. If so, what is it - how is it defined to work in principle? It’s certainly not meaningful to talk about experimental tests for something that you haven’t defined clearly. Just how do you propose that an “agent” could reach a decision that is not the result of either deterministic or random processes?

You said, “If there’s divergence, the crucial question is why?” and I agreed with that.

By thinking about it, weighing the evidence, grinding it through the vastly complicated meat-computer, looking inward and assessing one’s own state of mind, and so on. Those things we do every single day of our lives.

Randomness is a part of it…but not a major part. It’s like the randomness in a game of Monopoly: no two games are alike, but, ultimately, the great majority of Monopoly games play out very similarly.

As for the definition, you offered one, and I like it. The fact that I might have chosen differently. I believe that is a fact, and that I might, truly, have chosen differently, at just about every point of choice in a long lifetime. One interesting way I can justify this is by “second chances,” when a very similar choice has to be made to one that was made before.

(You can say, “It isn’t identical,” and that doesn’t really trouble me. I acknowledge the possibility of straitjacketing volition by cementing it into a context that does not permit choice. If I drop you from an airplane, you do not have the “free will” not to fall. Free will works in the context of working decisions, not artificially contrived circumstances.)

And which part of this do you claim is not deterministic?

You just seem to be reverting to the straw man that “no free will” means that we don’t make choices. As I have said quite clearly, of course we make choices, and nobody claims otherwise. Once again, the “no free will” claim is simply that phenomenon called choice is deterministic computation.

So I want you to explain just what component of the choosing process you think is not deterministic computation, and how you think it works? Just saying it’s “complicated” is dodging the question. Of course our brains are complex. If you claim that we do not make decisions deterministically (i.e. for reasons, including external data and the internal state of the brain), then how do you propose that we make them?

I’m happy that you are untroubled. But I also haven’t the faintest idea why you think this is relevant. Literally nobody in the entire history of this debate has ever claimed that we constrained to make the same choices even under different circumstances. That would be ridiculous.

No.

I have been painfully consistent on this. Painfully. Consistent.

It is your own failures of understanding that are causing the perceived fracturing of meaning. You look at the world through a broken lens, and then blame other people for not appearing as consistent bodies. That’s a bad play. A better move on your part would be to fix your lens, rather than blaming others for the flaws you think you see.

In this context, that means: learn the actual definitions. Learn what people who espouse determinism actually mean when they use that word. In every single post I have ever written on this topic, I have been using this definition: the standard, plain, boring, mathematical definition. It’s been clear for thread, after thread, after thread, that you do not understand this definition. That’s the crack in your lens. You don’t know what it is, don’t comprehend its implications, don’t understand that when the vast majority of (scientifically literate) people have some inclination to believe that the universe is deterministic this is the definition they are using. We are almost all of us consistent on this. You are the odd one out.

The problem isn’t with the entire rest of the (scientifically literate) world. The problem here is the faulty lens you are carrying around. Fix that lens. Learn the actual definitions, straight from the people who actually do espouse determinism.

You are not a member of that club. You do not get to define our words for us, nor especially to interpret us poorly and then accuse us of inconsistency.

Yes, it is.

We’re not “switching” definitions when we’re discussing a system of differential equations,* or when we’re discussing “free will” (whatever that is supposed to mean). We’re using exactly the same definition for both purposes. When (scientifically literate) people advocate for determinism in “free will” discussions, this is the definition that the vast majority of them are using. It is a painfully consistent definition.

*It’s worth pointing out that the Schroedinger equation itself is a partial differential equation. The entire point of the MWI is that that equation is all you need (theoretically) to explain the universe: the deterministic evolution of the universal wave function.

This is like two years old at this point, but it’s worth re-posting because (again) this did not penetrate your understanding.

Painfully. Consistent.

If it turned out that the world were such as to allow meeting this Jesus guy in the afterlife, then well, seems like those people got lucky; and if that were the case, then I would want to know. In the end, it’s this wanting to know that drives me—who gets what they want, and who doesn’t, really doesn’t have much of an impact. There’s enough people, like you, who want the world to just be a deterministic puppet show—those people loose out.

Well, then at least point out the flaw in my argumentation! To me, it seems quite clearly to be the case that if every account of A occurring necessarily includes an agents choice, then that choice is an irreducible element of bringing about A. So why is it wrong to say that choosing A is what brings about A?

Reform of the justice system is something that is necessary quite apart from questions of free will—indeed, ultimately, they don’t really have anything to do with it.

I agree; hence, my attempt to explain to you how the universe really is, even though it appears to contradict cherished beliefs of yours. And hence what I’m not doing is discounting your views based on a caricaturesquely simplistic reading of them.

It’s not wrong to say that choosing A brings about A. Nobody disputes that our choices have real effects. If I choose strawberry ice cream, I expect to get strawberry ice cream. But this has nothing to do with free will. Free will is a (flawed) account of the process of choice. I don’t think the fact that something is computationally irreducible constitutes grounds to ascribe mysterious magical properties to it. Determinism does not imply that, as a practical matter, it is necessarily possible to predict every detail of the evolution of the universe in advance. Rather, it is a description of the process by which the universe evolves. Computationally irreducible or not, if the process by which choices are made is deterministic computation, there is no free will.

If you claim that free will does exist in a deterministic universe, then you are (by definition) a compatibilist, and for me that’s just a distraction from the central point that there is no free will. You are just trying to “rescue” free will by defining it as something completely different from the common could-have-done-otherwise-in-identical-circumstances intuitive sense.

On the contrary, I think it’s fundamental to criminal justice. If there is no could-have-done-otherwise free will, there is absolutely no possible moral justification for purely retributive justice. We all accept that someone who committed a crime because of a brain tumor that altered his judgment is in some sense “not culpable” for his actions. But, logically, someone who committed a crime without a brain tumor is no more “culpable”, since their choices were no less deterministic processes than those of the person with the tumor. That does not imply that they should not be punished, and perhaps even killed, as a means to keep society safe and to deter others. But it means that there is no moral justification for inflicting harm upon them purely for retributive purposes. It makes no more sense than torturing a lion because it killed an antelope.

Then I would say that you use the word ‘choice’ differently from most people. Generally, choice implies alternative: both choosing A or B ought to be possible. This isn’t the case in strictly deterministic models: A is set as being what happens, from essentially the dawn of time. Choice, or the subjective impression of making a choice, is just along for the ride; the real reason why A happened is not that I chose A, but the decay of some radium atom ten thousand years ago, or what have you.

You say it yourself in your account of how genuine free will implies culpability: if it is not the choice of the agent that is responsible for the crime committed, then it is not the agent who made that choice that is responsible, but some other factor, be it a brain tumor or what have you. Aside from the fact that it’s never that simple (perhaps they got a brain tumor through indulging in some form of dangerous lifestyle), I think that’s a mistaken reading of the implications of guilt, but well.

I’m not talking about predictability, but logical implication—that’s a very different concept. There’s lots of things we can’t predict, due to lacking the necessary resources, but even given access to infinite resources, we could not predict what does not logically flow from prior facts.

Again, that’s a simplistic reading. As I’ve pointed out, I think that what people really want is responsibility for their actions, with free will being the way to get that. But on my model, there is such responsibility: you can’t say that the choice you made was due to a radium atom decaying ten thousand years ago, not even in principle; the choice you made was due to your so choosing.

Again, then this is true of all concepts who have had their meaning refined in the course of further study: then geneticists don’t talk about genes proper, particle physicists don’t talk about particles, and so on; but in reality, it’s of course inevitable that concepts evolve, become more precise, upon being studied.

There’s no such justification even in the case of ‘could have done otherwise’-free will, since it requires a moral axiom saying something to the tune of ‘guilt merits punishment’, but there is absolutely no reason to accept this. Indeed, here is a case where we have a clear-cut question of effectiveness, or objective measures: a punitive system is bad if it doesn’t do the job it was designed to, which is something you can test, and study empirically. Questions of metaphysics do not—and should not!—have any bearing on this; either we are effectively combating the diseases of society, or we are not. What’s the root cause of these diseases is ultimately beside the point, and I’d argue it’s already a dangerous misconception to think otherwise (because it implies acceptance of this sort of ‘guilt merits punishment’ thinking).

Well, the semantics here are a point of contention that was raised earlier. Some no-free-will advocates prefer to say “we do not choose”, meaning that we do not choose freely (in the “free will” sense). Personally, I think that’s misleading, because it seems rather frequently to lead to the (rather bizarre) misconception that we are claiming our brains do nothing at all! I prefer to retain the word “choice”, since it applies to an objective, observable phenomenon that we need still need a word for. If you offer me several possibilities, all of which are possible in principle, my brain does its thing and tells you which one. I prefer still to call that “choosing”. After all, we would still say that a chess computer “chooses” its next move. It’s just that the account of the process of human choice does not involve a magical homunculus. Rather, choice is a deterministic process of computation.

I think this begs the question. Since the raw intuitive concept of could-have-done-otherwise free will is incoherent nonsense, I am highly skeptical that it’s a useful idea that just needs to be refined. I could equally well say that “free will” is analogous to creationism or alchemy, or more generously Lamarckism or the luminiferous ether, ideas that we simply discarded and replaced with better ones that comport with reality. (In fact, creationism, alchemy, Lamarckism and the luminiferous ether are all better ideas than free will, because at least they were somewhat coherent ideas; they just turned out to be empirically wrong.)

Ok, so you can’t predict the outcome of an irreducible process ahead of time even in principle. But the process of choosing is still deterministic. You made the rather unclear statement: “…the choice you made was due to your so choosing.” Do you disagree with this description: “The choice you made was a deterministic computational process”?

To me, it’s just a complete non sequitur when you imply that what you describe here is even remotely congruent with could-have-done-otherwise free will. Computational irreducibility is interesting, but seems to me to have no relevance whatsoever to the idea of free will.

ETA: As I said, I really don’t follow how you (or Wolfram for that matter) make the leap to supposing that if the way the human brain works is computationally irreducible ==> it has free will. But it appears that you think the unpredictability is significant. There’s a relationship in the sense that if a supercomputer could predict every human decision, that would clearly falsify any notion of free will. But that doesn’t logically imply the converse: an inability to predict human decisions does not prove that there is free will. It’s necessary, but surely far from sufficient.