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Interview with Scott Aaronson

blogs.scientificamerican.com

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Re: Interview with Scott Aaronson

#51

Post by foldr »

davmre wrote: post #49
foldr wrote: post #36

The discussion of whether or not we have free will strikes me as confused. Aaronson suggests that we would clearly not have free will in a scenario where “Everything [we] did could be fully traced to causal antecedents external to [us], plus pure randomness—not in some philosophical imagination, but for real, and on a routine basis”. The caveat “external to [us]” is doing a lot of work here, but it really has no disc…

I think you're missing the point somewhat. Yes, Aaronson assumes that something like physicalism is true, which I think is fairly defensible as a 21st-century scientist. But the argument isn't as simple as "physicalism entails the absence of free will". His point is that even if our actions are (probabilistically) determined by a set of underlying physical laws, it may still be that the character of those laws is suc…

>But the argument isn't as simple as "physicalism entails the absence of free will".

Right, I said that's probably all he should say.

>His point is that even if our actions are (probabilistically) determined by a set of underlying physical laws, it may still be that the character of those laws is such that it is fundamentally impossible to predict future actions, in which case we would still have meaningful free will.

It's hard to see how it makes any difference to my level of freedom whether someone else can successfully predict what I'm going to do. You can predict pretty reliably that I'm going to have breakfast in the morning, but it's still a free decision on my part.

>but the characterization of free will in terms of the concrete question "is it possible to build a prediction machine?" seems like a useful and novel contribution that doesn't just reduce to the old question of "is physicalism true".

It seems to me that the question of whether or not we have free well is largely orthogonal to the question of whether or not our actions are predictable. I suspect that all four combinations of predictable/unpredictable and free/unfree are logical possibilities. So I think Aaronson is conflating a lot of things that ought not to be conflated, and which have been endlessly and subtly picked apart in a philosophical literature that he appears not to have bothered reading. (I haven't read that much of it either, but it already contains pretty much every idea about free will that is likely to occur to anyone in our present state of knowledge.)

Re: Interview with Scott Aaronson

#52

Post by foldr »

wfo wrote: post #43
foldr wrote: post #36

The discussion of whether or not we have free will strikes me as confused. Aaronson suggests that we would clearly not have free will in a scenario where “Everything [we] did could be fully traced to causal antecedents external to [us], plus pure randomness—not in some philosophical imagination, but for real, and on a routine basis”. The caveat “external to [us]” is doing a lot of work here, but it really has no disc…

Yes, very well put. I really enjoyed his technical answers, but when he dives into the philosophy I was disappointed to see the same very naive and narcissistic attitudes so many scientists have (that are even alluded to at the beginning of the article): you don't need to try to understand philosophy, just use your superior STEM brain and technical intuitions and if you think about it for a few minutes, with a health…

Agree completely. I don't think you deserve to be downvoted for saying that. Everything Aaronson's saying on this topic has been exhaustively discussed in the philosophical literature.

Re: Interview with Scott Aaronson

#53

Post by foldr »

davmre wrote: post #50
davmre wrote: post #49

Earlier quoted context omitted.

I think you're missing the point somewhat. Yes, Aaronson assumes that something like physicalism is true, which I think is fairly defensible as a 21st-century scientist. But the argument isn't as simple as "physicalism entails the absence of free will". His point is that even if our actions are (probabilistically) determined by a set of underlying physical laws, it may still be that the character of those laws is suc…

To follow up: I personally see some extra subtlety here, in that even if a prediction machine did exist, we could still have a meaningful form of free will, because that machine would be governed by Rice's theorem ( https://en.wikipedia.org/wiki/Rice's_theorem ), which says that in general the only way to predict the outcome of a computation is to run the computation. (this is closely related to the halting problem).…

I don't exactly disagree with you (although let me point out that I said the discussion was confused, not Scott), but I'm not sure where people get the impression that philosophers aren't engaging with physicists on these questions. The ramifications of quantum physics for free will have been discussed endlessly by philosophers, and often by philosophers who have a significant amount of training in physics.

Re: Interview with Scott Aaronson

#54

Post by davmre »

foldr wrote: post #51
davmre wrote: post #49

Earlier quoted context omitted.

I think you're missing the point somewhat. Yes, Aaronson assumes that something like physicalism is true, which I think is fairly defensible as a 21st-century scientist. But the argument isn't as simple as "physicalism entails the absence of free will". His point is that even if our actions are (probabilistically) determined by a set of underlying physical laws, it may still be that the character of those laws is suc…

>But the argument isn't as simple as "physicalism entails the absence of free will". Right, I said that's probably all he should say. >His point is that even if our actions are (probabilistically) determined by a set of underlying physical laws, it may still be that the character of those laws is such that it is fundamentally impossible to predict future actions, in which case we would still have meaningful free will…

It feels like this is mostly a disagreement over language. We all agree that determinism and "predictability" are independent questions. You've equated "free will" with non-determinism and therefore see predictability to be orthogonal, whereas Aaronson equates "free will" with non-predictability, making determinism orthogonal though I imagine he'd argue for it on other grounds. It's not clear that there's an actual disagreement over anything except which words to use for which concepts.

FWIW, I think Scott has read more of the philosophical literature on free will than probably anyone else in the world with a comparable level of quantum-physical expertise. If he's too confused to be allowed to discuss these issues, then what is the path by which philosophers expect to stay relevant and up-to-date with new knowledge? A field whose currency of legitimacy is "you must have devoted your life to understanding every detail of dispute in the existing literature" is not a living field that hopes to learn from outsiders and grow with new scientific inquiry. I think the best philosophers recognize this, and are willing to engage more broadly.

Re: Interview with Scott Aaronson

#55

Post by foldr »

davmre wrote: post #54
foldr wrote: post #51

Earlier quoted context omitted.

>But the argument isn't as simple as "physicalism entails the absence of free will". Right, I said that's probably all he should say. >His point is that even if our actions are (probabilistically) determined by a set of underlying physical laws, it may still be that the character of those laws is such that it is fundamentally impossible to predict future actions, in which case we would still have meaningful free will…

It feels like this is mostly a disagreement over language. We all agree that determinism and "predictability" are independent questions. You've equated "free will" with non-determinism and therefore see predictability to be orthogonal, whereas Aaronson equates "free will" with non-predictability, making determinism orthogonal though I imagine he'd argue for it on other grounds. It's not clear that there's an actual d…

I wouldn’t equate free will with physicalism. It’s possible that physicalism might entail the absence of free will (I don’t claim to know the answer to this question), but it’s pretty clear that the entailment doesn’t go in the other direction.

I’m a bit frustrated here, because physicists often seem to retreat to this position that it’s all just a question of terminology once people start pushing back against their philosophical claims. If Aaronson actually is using terms in such a weird way as you suggest, then I just have no idea what he is on about. We already have a perfectly fine word that means unpredictable; there’s no need to repurpose “free”.

I admit that I have no way of knowing what he has or hasn’t read, and my comment on that was snarky. But he doesn’t refer to any philosophical work in the interview, and I couldn’t find much published work by him that really engages with the current literature.

Re: Interview with Scott Aaronson

#56

Post by hkmurakami »

zodiac wrote: post #48
eachro wrote: post #46

Does anyone know why he's leaving MIT for UT Austin?

He has a blog post about it - http://www.scottaaronson.com/blog/?p=2620

> I wasn’t forced to leave MIT over anything here on Shtetl-Optimized.

> Bizarre as it sounds, CS departments mostly cared about what actual research we were doing and could bring to them! So students and faculty afraid to debate anything controversial online under their real names, however politely, should know that even in 2016, the banner of academic freedom yet waves.

I wish we could say the same about private industry -- most notably our employers and our funders.

I am reminded of this:

>I think the web has made us all write more defensively, and it’s a shame, because we’re effectively contorting our communication style to defend against a small minority of mean-spirited and uncharitable actions by some. Actually, as I say that, I instinctively feel the need to hedge myself–I don’t believe that people are really mean-spirited (well, perhaps some are–gak I’ve done it again!), but there’s something about commenting about stuff on the internet with people you’ve never met that seems to bring out the worst in people. (https://pchiusano.github.io/2014-10-11/defensive-writing.htm...)

Re: Interview with Scott Aaronson

#57

Post by moultano »

foldr wrote: post #55
davmre wrote: post #54

Earlier quoted context omitted.

It feels like this is mostly a disagreement over language. We all agree that determinism and "predictability" are independent questions. You've equated "free will" with non-determinism and therefore see predictability to be orthogonal, whereas Aaronson equates "free will" with non-predictability, making determinism orthogonal though I imagine he'd argue for it on other grounds. It's not clear that there's an actual d…

I wouldn’t equate free will with physicalism. It’s possible that physicalism might entail the absence of free will (I don’t claim to know the answer to this question), but it’s pretty clear that the entailment doesn’t go in the other direction. I’m a bit frustrated here, because physicists often seem to retreat to this position that it’s all just a question of terminology once people start pushing back against their…

I think Aaronson believes the following. If there are provably no experiments that could differentiate a propery X from "free" then X is equivalent to "free." I think unpredictability passes that test.

Re: Interview with Scott Aaronson

#58

Post by TheOtherHobbes »

Xcelerate wrote: post #41
typon wrote: post #23

Earlier quoted context omitted.

But that's pretty much what Aaronson is implying. That physics can be cold, calculating, unbiased while the social sciences are the opposite. There is plenty of dogma in the physics world as well. For example, just look at the way people defend their favorite interpretation of quantum mechanics as absolute truth.

> just look at the way people defend their favorite interpretation of quantum mechanics as absolute truth. Yeah, but these people are rarely actual physicists. A physicist might discuss "interpretations of quantum mechanics" over lunch with a colleague in a fun, speculative way, but it makes little difference on the research they perform. More importantly, it doesn't affect the predictions that their research makes.…

It absolutely does affect the predictions research makes, because funding and PhD students are assigned to whatever models are most popular at the time. For a long time that was string theory, and a lot of departments considered other approaches to be non-optimal for career progression.

Which sounds fine if you believe that heterodox but still valid science gets into the mainstream eventually - like (e.g.) the theory of continental drift did.

But what if useful science falls through the cracks? What if we could have had a valid theory of quantum gravity by now, from a left-field approach that never had funding or PhD students to research it?

How would anyone know?

Re: Interview with Scott Aaronson

#59

Post by wfo »

foldr wrote: post #52
wfo wrote: post #43

Earlier quoted context omitted.

Yes, very well put. I really enjoyed his technical answers, but when he dives into the philosophy I was disappointed to see the same very naive and narcissistic attitudes so many scientists have (that are even alluded to at the beginning of the article): you don't need to try to understand philosophy, just use your superior STEM brain and technical intuitions and if you think about it for a few minutes, with a health…

Agree completely. I don't think you deserve to be downvoted for saying that. Everything Aaronson's saying on this topic has been exhaustively discussed in the philosophical literature.

I don't think I deserve it either but I am not surprised or particularly offended. Pop scientists like Dawkins and NDT are rightly mocked when they say things like this because we can safely feel superior to them, but a tech golden boy like Aaronson can do the exact same thing and since he knows about quantum and does computer science it doesn't matter what he says or how far out of his depth he ventures any comment about him which doesn't border on hero-worship is verboten.

Downvotes or no it's worth saying. Defending any social science or humanity at all is hard work on a forum like this, but I think it's important.

Re: Interview with Scott Aaronson

#60

Post by pron »

AndrewKemendo wrote: post #44
foldr wrote: post #36

The discussion of whether or not we have free will strikes me as confused. Aaronson suggests that we would clearly not have free will in a scenario where “Everything [we] did could be fully traced to causal antecedents external to [us], plus pure randomness—not in some philosophical imagination, but for real, and on a routine basis”. The caveat “external to [us]” is doing a lot of work here, but it really has no disc…

The caveat “external to [us]” is doing a lot of work here I think it's just sloppy discussion. Any hard-determinist will say that every interaction is pre-determined based on a previous interaction. The compatibilist approach tries to reconcile hard-determinism with the illusion of free will in a reference frame of the individual - but I think falls apart. I think Aaronson is trying to convey this particular philosop…

> Godel explored this exhaustively and concluded (though did not prove) that this is not possible

While I agree that Aaronson's take on philosophy is not very original or profound, I don't think that Gödel concluded anything of the sort, and if he said something in that vein (assuming you're referring to the discussion on mechanism in the link you're provided), it is more an expression of his faith that any problem can be solved (and since not every problem can be solved by a machine, the mind is more powerful than any machine) -- hardly a conclusion.

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