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by cthalupa 2750 days ago
>So people only claim to be incompatibilists when they confuse determinism with fatalism. Regardless, they tended to agree strongly with Compatibilist moral reasoning.

I pretty strongly disagree with this statement. I am not a compatibilist, but I am fully aware of the differences between fatalism and determinism. If I believed in fatalism then I would believe that If am fated to recover or die from an illness, it would happen regardless of whatever actions I take, etc. With determinism I believe the outcome from whatever illness I receive will depend on the illness, the actions taken, my overall health, etc. etc. etc., all the way back through the causal chain at the start of the universe.

I believe everything adheres to causality. Compatabilists and I would both agree that we cannot determine our motivations, but then we would disagree if there is "free will" in the choice we make based on those motivations. My brain is a physical entity, ruled by the laws of physics. Every decision I make is ruled by those laws, because my brain cannot work in any other way. If we had perfect knowledge of how the brain works (and I believe this is possible), you can boil down the thought process of "I have a memory of stubbing my toe and it hurt, so I will make the conscious effort to avoid stubbing my toe" to the composite physics that result in said thought process. Given all of the same inputs, the same outputs will come in to play.

This somewhat ignores the randomness of the quantum world, but I don't think it particularly effects the outcome - if time could be rewound to the start of the universe, and the play button pushed, quantum effects would likely mean that we do not end up with the same universe we have today, but I don't see how having randomness fundamentally would mean that I as a human being have any increase in my ability to come to a decision. The inputs would be different, if I were to exist at all, but I would still be bound by the same laws of physics that determine how my brain functions.

Compatabilitists and I sharing similar ideas about moral reasoning doesn't change that. My "moral reasoning" is that things like the laws we create are still all based on causality, and that the actions people take are in turn causally related to the inputs we give them, such as the laws. Changing this inputs results in different outputs when considering things like potential futures, which are then inputs into the decision making process, etc.

But I also believe that it doesn't really matter, as far as day to day life goes. At current, humans lack the ability to perceive life in such a way that we can figure out how any of that shit actually works. I can behave and think in a way that is similar enough to how free will would work that it doesn't matter. To change this, we would need perfect knowledge of how basically everything works, have the ability to measure every necessary input in the system, and calculate the outcomes. If we are ever able to reach that point, I'm pretty sure it'll be so far into the future it's nothing worth worrying myself about.

3 comments

To change this, we would need perfect knowledge of how basically everything works, have the ability to measure every necessary input in the system, and calculate the outcomes. If we are ever able to reach that point, I'm pretty sure it'll be so far into the future it's nothing worth worrying myself about.

Its pretty easy to argue that this is impossible. To exploit determinism to 'predict the future' you'd have to simulate a large chunk of reality at the sub-atomic level. Arguably, you might have to simulate the whole universe. But lets just say you were trying to simulate our planet - you would need a computer running a model of the world at the sub-atomic level and somehow running it faster than the world itself unfolds. I'm 100% sure that would be impossible. Also, there's the whole 'sensitive dependence on initial conditions' for your simulation (see chaos theory etc).

So you can think of the universe as a computer that is calculating its own future in real time. There is no way to 'get ahead' of the univere's own unfolding. As such the fact that it might be deterministic becomes irrelevant because there is no way to exploit that determinism. Simply put: It may be deterministic but its fundamentally unpredictable.

>Its pretty easy to argue that this is impossible.

Yep! It is very likely that this is impossible.

>you would need a computer running a model of the world at the sub-atomic level and somehow running it faster than the world itself unfolds. I'm 100% sure that would be impossible.

I'm not 100% sure.

The universe? Sure. We know that's impossible because of our understanding of physics - we cannot store the amount of information in the universe in anything smaller than the universe, much less compute on that information. Every single state we compute would again require the entirety of the universe to be stored, plus any transitional states in between. But I can't say with 100% certainty we'll never be able to compute everything necessary to predict how humans behave.

It might be, at some point in the future.

But my point was less about the theoretical possibility of this and more of how the fact that it currently is not, and is unlikely to be so at any point that is particularly relevant.

Chaos theory is what seals the deal on this one.
This is called Laplace's Demon. It has been disproven by chaos theory.
>This is called Laplace's Demon.

Pretty close!

Laplace's Demon also talks about seeing the past - which my hypothetical does not. Nor am I concerned with calculating the entire universe, only the portions that would effect human cognition - just that which will be observable. Much of the universe is beyond our light cone, and unless we are in the center of the universe, almost certainly the vast majority is, and none of that needs to be calculated. Severely restricts the requirements vs. Laplace's demon.

>It has been disproven by chaos theory.

Not quite! Chaos theory relies on imperfect information. It does nothing to disprove Laplace's Demon, which involves perfect information. For chaos theory to be applicable, there has to be minor variations between the initial conditions. Chaos theory is not a theory that we cannot predict things because they are unpredictable, it is a theory that says that minor variations at the onset can result in huge differences in the eventual outcome. These problems only exist if you do not have perfect information.

Thermodynamic irreversibility disproves Laplace's Demon's seeing into the past portion. The Copenhagan interpretation of quantum mechanics also puts a nail in the Demon.

Things get interesting if we are ever able to create a 300 qubit quantum computer - at this point, you can perform more calculations in an instant than there are atoms in the known universe. Is that granular enough to accurately determine human behavior?

The whole computer thing is more an aside than anything, though - just providing a hypothetical in which case free will not existing would actually have practical application on how humans live. Without it, I can't think of any reason why we should behave in any other way than we do, regardless of the underlying truth.

Lets say you have that 300 qubit quantum computer, and you only need to simulate your own light cone. Trouble is, that quantum computer is also in your light cone. So to accurately simulate your light cone, your simulation has to include itself, recursively. Hence: not going to happen.
Not if you're only attempting to prove or disprove free will and run the simulation after the fact. If you can get perfect knowledge of the starting conditions for everything in the light cone, run it, and then compare it against what actually occurred.

It might not work for telling the future, but if you limit the computation to see if it accurately models what is now history, you don't need it to simulate itself.

Oh and also your simulation would most likely be part of the region you were trying to simulate, meaning you'd have to simulate your simulation as well. Doubly impossible
You've written a lot of text, most of which I might agree with, but you haven't demonstrated why any of it precludes the existence of free will.

Compatibilism is specifically the position that free will is compatible with deterministic agents. Merely stating you disagree that this qualifies as free will isn't particularly compelling. Compatibilism makes sense of our moral language, we clearly have the free will described by Compatibilism, and it's strongly predictive of our moral reasoning as the paper I linked shows.

That seems to describe what most people mean when they use the term "free will" quite well, just like "day job" describes quite well what I do every weekday from 9AM to 5PM.

>but you haven't demonstrated why any of it precludes the existence of free will.

Except I don't need to. Compatibilists haven't proven the existence of free will, so the null hypothesis still holds true, at least for now.

Throughout the comments here you seem to continually rely on the fact that professional philosophers strongly agree with the idea of compatabilism, but from my point of view, it doesn't really matter what philosophers think. It's a matter of what the science says.

I don't see any real incompatibilities with moral reasoning between a universe where there is no free will and one where it is compatible with determinism, so saying that compatbilist moral reasoning is predictive of how we generally behave is not an argument for free will.

> I don't see any real incompatibilities with moral reasoning between a universe where there is no free will and one where it is compatible with determinism, so saying that compatbilist moral reasoning is predictive of how we generally behave is not an argument for free will.

Prove that "a universe without free will but behaviourally indistinguishable from one that features Compatibilism" is actually a coherent definition/non-empty set.

Compatibilism entails that any universe featuring intelligent agents acting on reasons and capable of understanding and learning from their actions will have free will. So basically, you're claiming that a universe that features such intelligent agents is indistinguishable from a universe that has no such intelligent agents.

> Except I don't need to. Compatibilists haven't proven the existence of free will, so the null hypothesis still holds true, at least for now.

I honestly don't understand what confusion would lead you to make such a statement. Null hypotheses are simply not relevant to this sort of question. What populations are you comparing here exactly?

Secondly, Compatibilism describes exactly what humans do because it's compatible with both deterministic and indeterministic worlds (see point above re:universes with Compatibilism). Compatibilist free will clearly exists in our universe virtually by definition, ie. we are clearly intelligent agents acting on reasons and capable of understanding and learning from our choices.

> Throughout the comments here you seem to continually rely on the fact that professional philosophers strongly agree with the idea of compatabilism

Because most people don't have the requisite knowledge to evaluate possibilities that require profound domain knowledge. Would you be similarly derisive if I referenced the medical consensus when wading through a health debate?

>Prove that "a universe without free will but behaviourally indistinguishable from one that features Compatibilism" is actually a coherent definition/non-empty set.

It being at all meaningful for me to do that relies Compatibilism having been proven to be correct. There's no evidence that this is the case.

>I honestly don't understand what confusion would lead you to make such a statement. Null hypotheses are simply not relevant to this sort of question. What populations are you comparing here exactly?

What? The null hypothesis is 100% relevant to this sort of question. The scientific null assumption is that something doesn't exist. If you are claiming it does, you're the one that needs to prove it.

>Because most people don't have the requisite knowledge to evaluate possibilities that require profound domain knowledge. Would you be similarly derisive if I referenced the medical consensus when wading through a health debate?

Philosophers do not have profound domain knowledge in determining how the universe actually works. Physicists do. The medical consensus question makes no sense because that is a false equivalency.

> The null hypothesis is 100% relevant to this sort of question.

Take a look at the actual definition of null hypothesis and tell me how it's relevant: https://en.wikipedia.org/wiki/Null_hypothesis

You're suggesting there's no relationship between what two phenomena when it comes to free will?

> The scientific null assumption is that something doesn't exist.

No it's not. Science is agnostic on such questions until there's evidence, and that's the proper answer. Making a definitive claim of existence or non-existence both require proof.

> It being at all meaningful for me to do that relies Compatibilism having been proven to be correct.

Lay out what constitutes proof of such a question, because I frankly think you're very confused either about what Compatibilism actually says, or what the whole free will debate is actually about.

> Philosophers do not have profound domain knowledge in determining how the universe actually works.

Fortunately, the philosophical question of free will is not about how the universe works.

From the very Wikipedia article you are attempting to use to say I'm using it incorrectly:

>Scientific null assumptions are used to directly advance a theory. For example, the angular momentum of the universe is zero. If not true, the theory of the early universe may need revision.

We have not proven that the angular momentum of the universe is zero. We assume it is, and have created our equations of how the universe works assuming this, and those equations have accurately described how the universe works.

However, it is not impossible that the universe is has angular momentum, and some scientists have proposed that it does, actually, and have some evidence that backs their claims. However, it hasn't been proven, so most scientists still work under the assumption that the angular momentum is zero.

>Fortunately, the philosophical question of free will is not about how the universe works.

Uh. What?

Whether or not we have free will is 100% about how the universe works. Either we have it, and the laws of nature allow it, or we do not.

>What? The null hypothesis is 100% relevant to this sort of question. The scientific null assumption is that something doesn't exist. If you are claiming it does, you're the one that needs to prove it.

That's not what the null hypothesis is.

It very much is. Please see my response at https://news.ycombinator.com/item?id=18610573
>so the null hypothesis still holds true

And who said the existence of free-will is the null hypothesis?

>And who said the existence of free-will is the null hypothesis?

How could it not be? You don't assume that literally everything is true without evidence of its existence.

Otherwise there is an infinite amount of an infinite variety of things existing in my room right now that I can't observe.

I take the computational approach. Even if a system was computable in a finite time, if that time is too long, then effectively for all practical purposes the system is computationally intractable.

I find even the idea that we could one day compute the human brain completely preposterous. We can't even compute water flowing in a pipe today (I'm saying this as an effective non-expert who has dabbled a bit in computational physics).

So, if the philosophical basis is that "if we can deterministically compute something, it's deterministic" then human cognition at the moment is most indeterminate.

Free will or no free will, we really can't know the difference. So it's best to behave like you have a free will, and own your own actions as far as you can.

This is a slight modification to Pascal's gamble :)

Sorry, I think I must have written this in such a way that some people are mistaking my point. I'll try to clarify. :)

>So, if the philosophical basis is that "if we can deterministically compute something, it's deterministic" then human cognition at the moment is most indeterminate.

My belief, based on my understanding of physics, is that human cognition is deterministic, regardless of whether or not we can compute it.

But I do largely agree with your broader point that whether or not we have free will should have little impact on the inputs in our system. Even if I believe that everything is deterministic and we have no free will, I can't use that information in any practical way, and human cognition (or perhaps more accurately modern Westerner cognition) is slanted towards believing in something resembling what we call free will. No reason to worry about it for anything beyond philosophical discussions. I brought up the computation as a hypothetical point at which acting differently would matter.

> So, if the philosophical basis is that "if we can deterministically compute something, it's deterministic" then human cognition at the moment is most indeterminate.

I think computational complexity is important, but I also think it's important not to conflate "unpredictable" with "indeterminate", even if they are behaviourally indistinguishable.

> Free will or no free will, we really can't know the difference. So it's best to behave like you have a free will, and own your own actions as far as you can.

Dennett calls this the "intentional stance", ie. that any system of sufficient complexity should be treated as if it were acting with intent.