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> If it was just classical physics, then you get yourself into the thinking that you can rewind time and all the "billiard balls" knock into each other the same way, which is why you order a soup and not a sandwich every single time on that day.

I don't understand this line of reasoning. If I ordered a soup for lunch, and then time is rewound and I order a sandwich instead, it would appear that my choice is in fact random and therefore I most definitely do not have free will. If rewinding time is sufficient to change my past choices, doesn't that utterly demean them? I might as well flip a coin.

I view this the same way. Determinism vs randomness says nothing about free will.

I think the problem with arguments regarding free will is that it's very hard to define (like consciousness for that matter). I am my brain. My brain controls what I do. Therefore, I control what I do. Only if we lift up our consciousness or free will as something higher than our brain does this become a problem.

The fact that my free will is deterministic, that is, a consequence of how the brain is structured and how the environment looks, does not change the fact that I, that is, my brain, controls what my body does. If anything, randomness makes this worse - then it is not my brain controlling my body, but some random result of a wave function collapse.

Yes, to me that seems the only sensible way to interpret free will.

I think that the whole determinism vs randomness debate boils down to the fact that when we make a choice, for example whether to order soup or a sandwich, we have to hold the belief that either choice is possible. We can simulate ourselves in our mind taking either decision, evaluate pros and cons, and use the results to act. In that sense, because it is compatible with many counterfactuals, our internal self-model is decidedly non-deterministic. And if you think about it, it has to be non-deterministic in order to be a useful decisional tool: considering what would happen if you did X or Y is the foundation of deliberation.

The trick, though, is that ultimately this is just epistemological non-determinism: you don't know what is going to happen, and you can't know, because you are in the process of figuring it out. When I am looking at the menu, I think it is possible that I will order a soup or a sandwich, just like I think it is possible that they are out of soup, even though there is a definite answer to whether they do or not. I just don't know it. Our misstep is to (intuitively) extrapolate that if we can't know what we will choose, then no one else can.

That's why physicists are so opposed to super determinism because like you say it would make life 'utterly meaningless' (I dont agree, a bit dramatic).

Super determinism is the unpopular answer that solves many problems in quantum mechanics and relativity.

It also makes a lot of sense if you think of the universe as pre-rendered, just like you would a CGI movie. Determine where all the particles land upfront throughout time and then play it back like a movie.

Life can still be fun even it is pre-rendered. Like a movie you don't know what's going to happen next anyways.

It could be like an atheist's version of God, taking in comfort in knowing whatever happens was going to happen anyways. Enjoy the ride.

Physicists don't largely choose physical theories on whether they make life meaningful or not. I think you're thinking of religious people.

I'm not. Otherwise why would physicists support the concept of free will so strongly without any evidence for it. It is borderline religious. The video I posted above says as much.

IANAP, but the actual definition of Bell's free will argument is a bit more nuanced, and was probably an unfortunate term to use to describe it.

The reason that super determinism is rejected is because (in the usual understanding) that it requires that the initial state of the universe is set up incredibly precisely to make all subsequent measurements appear to violate Bell's inequality, even though reality isn't actually like that.

So if we set up a quantum measurement and make a decision based on photons of light emitted from distant stars, the experimenter deterministically chooses to make just the right measurement that would make the universe look like it was violating the inequality. Including all the matter between us, and the atoms in the neurons in the experimenters brain, and the photons that were emitted before any of that existed.

This is why super determinism is rejected. It would mean that we are not "free" to choose the experiments and measurements we perform. The universe would be essentially conspiring to deceive us at all levels, including what science we do, the results we receive and the conclusions drawn from it. Which is why it would invalidate the scientific method itself. We couldn't trust anything we thought we knew.

Sabine has a different take from what I can tell. If you allow backwards causality, the measurement act is not independent of the thing being measured. See this blog entry and the comments:

http://backreaction.blogspot.com/2019/07/the-forgotten-solut...

Physicists essentially like "free will" because it is essential to do physics in a meaningful way (*). If you have something like superdeterminism then everything can be set up to make it look like your experimental results mean something, but while you're not looking anything could be happening, since your choice of what experiment to do can be correlated with the system you're observing without you knowing it.

For example you can have a system with two possible states, A and B. My decision to do experiments some superdeterministic setup is correlated with the state of the sytem so I only do experiments when the state of the system is A. I conclude that A is a physical law, but I'm completely wrong, its quite often B but I am only "choosing" to do experiments when it A.

(*) this is my opinion and the opinion of many, but absolutely not all physicists

Yes. Although it's technically a valid loophole, the likelihood the entire universe is set up to consistently give misleading results is extremely hard to believe.

The universe could still be entirely deterministic, in that your choice of experiment and measurement to make was fixed at the moment of creation. But you still believe that the results you are getting are a fair and accurate reflection of how the universe actually works.

Free will (in the philosophical sense) is irrelevant. Your choice of measurement is only influenced by what is happening locally to you at that time. The game isn't rigged to produce misleading results from the very moment of creation for all time.

> Physicists don't largely choose physical theories on whether they make life meaningful or not. I think you're thinking of religious people.

I disagree, I think quite the opposite.

Physicists often seem to adhere to a "religion" of sorts, that being atheism. Anything to get rid of the "God problem".

It's not all so cut and dry.

> “I believe in Spinoza's God, who reveals himself in the lawful harmony of the world, not in a God who concerns himself with the fate and the doings of mankind.” - Albert Einstein

I'm not religious.

There are many religious physicists. I won't get into the argument about whether atheism is a sort of religion.

But even if fervent atheist physicists are trying to remove the God Problem, how does that mean they are selecting physical theories to make life meaningful?

In my physics PhD a meaningful portion of the department was religious. Had more to do with country of birth than the thing they were studying.

Not sure why this was downvoted. I'm not attacking religious people, so apologies if I gave any offence.

Just observing that historically religion tends to select theories of the physical world that align with its moral and religious belief.

Note, I don't think Sabine's theory in this video actually is "superdeterminism" even though she called it that. It's rather "retrocausality", which is still magical but more limited.

However, there isn't an explanation for why it's limited - seems like if the partial case could happen then the whole thing could happen too. (there's a long argument about this in the comments of Scott's post)

> Life can still be fun even it is pre-rendered. Like a movie you don't know what's going to happen next anyways.

What if my life isn't "fun"?

A lot of people live out lives of complete suffering. Childhood cancer? Poverty? Disease? Genetic mental health issues? Inbreeding? Childhood trauma? That list goes on and on.

That isn't a movie I signed up for.

Does determinism think this is supposed to be a lesson of some sort?

Nothing about superdeterminism says you can't find ways out of suffering... to use the movie example, the movie may play out such that your life gets better! Or it won't... superdeterminism just says that those frames are already printed on the film, we just don't know what they look like yet because we can't perceive the future.

> Nothing about superdeterminism says you can't find ways out of suffering

Actually it does.

Your movie is going to play out the way it plays out, regardless of whatever you do. Throw your feet up in the recliner or struggle for that next promotion, doesn't matter. Brain cancer.

I just find this rubbish.

Religious people would say brain cancer was just part of gods plan. Determinism basically is the same plan just no god involved. Why is that rubbish? Because you don’t like it?

Do you find it rubbish because you don’t want to believe it’s true? Or because there’s holes in the logic?

You rejecting superdeterminism, deciding that your fate is up to you, and making positive decisions to improve your life, is great. Do that.

It may be though, that those positive decisions and deciding your fate is up to you, etc, was already printed on the film. Or if instead you just throw your feet up on the recliner and decide to do nothing, then that would have already been printed on the film as well.

If in a trillion years the universe ends and there’s a complete story to tell about everything that happened, and some external observer were to watch that story, they’d see you making whatever decision you made and your life turning out in a particular way. But they wouldn’t expect that if they rewound the film that things would somehow turn out differently.

But superdeterminism in the sense that Scott uses it doesn't just mean life is completely predetermined (I think that would be a fairly unobjectionable theory), it means that specifically the whole universe is predetermined in a way that just happens to cause human experimenters to choose measurement settings that accidentally reproduce the the values predicted by Bell's inequality.

It's that mind-blowingly unlikely coincidence with no explanation that scientists object to.

It's true that he uses it that way, but I think Sabine claims that's not the case and her theory is actually different. Other people with similar theories call it "retrocausal".

Scott doesn't believe it's possible for them to be different though.

IMO the concept of free will doesn't make sense, at least not without also believing in the existence of a soul.

If you were to make a decision that is not in some sense pre-determined by the structure of your brain (as shaped by biology and past experiences), it would be essentially random and just as meaningless as an uranium atom "deciding" to decay at some specific moment and not another.

But even though the arguments supporting free will at the ontological level is unconvincing, free will in the phenomenological sense is not the same.

I am of the hard determinist camp but I'm pessimistic about if we're ever going to be able to predict chaotic systems. Even if someone could predict what I'm about to do, this information would be fundamentally out of reach for me since getting this information would influence the outcome (also, maybe the predicting machine itself would causally perturb me enough to not be able to make meaningful predictions).

Free-will fits perfectly fine into the evolutionary theory.

When prey are faced with predators on the open savannah, they may be in "unconscious mode" when grazing the grass, but if they glimpse a predator, ears and tail go up, head swings, and they have to make a decision.

How is that any different from an artificial neural network taking inputs and making decisions. Are you saying the ANN has free will as well?

Free will, as physicists talk about it, essentially means that my choice to perform some experiments is independent of the state of the system I'm experimenting on.

In other words I want it to be true that looking at the system doesn't tell you anything about when / whether I'm going to be performing experiments on it today, and more specifically I don't want you to be able to predict which measurements I'm going to do based on the system alone (i.e. without asking me).

This notion of free will is (as far as I can tell) completely necessary in order to meaningfully do physics at all.

If you reduce free will to randomness, an electron has free will. If you don't, then you propose that free will is somehow disconnected from physical causality. That is at odds with our understanding of the universe.