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Does quantum theory imply the universe is preordained?

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Re: Does quantum theory imply the universe is preordained?

#171

Post by mewpmewp2 »

pshirshov wrote: post #170
mewpmewp2 wrote: post #164

Earlier quoted context omitted.

Yes, but this type of behaviour occurred logically from emergent behaviour because it performed well throughout evolution. Groups who were able to keep their members in check were the groups who won out. So we have the inherent motivation and desire to punish others to keep them in check. There's ever lasting power balance within a group, where group will perform well if everyone does well for the group, leading to t…

You can't have desires or motivation in a determenistic world.

You can. It's just chemicals and signals that you "feel".

Re: Does quantum theory imply the universe is preordained?

#172

Post by nwiswell »

dotsam wrote: post #86
nwiswell wrote: post #81

Earlier quoted context omitted.

> If there is any guiding light to the randomness, any pattern to how the random choices come out, then it's not really random, is it? Well, yeah, that's the point. By definition, a deterministic model of reality means there is no room for a free agent to make decisions: things couldn't have worked out another way. But a mechanism that appears random provides at least the potential for a free agent, since randomness…

I find the idea of computational irreducibility useful for rescuing a type of free will in a fully determined world. Computationally irreducible programs are perfectly deterministic, yet you can't predict the output before you run them, and nor are there any shortcuts to get there before running them for the first time. The program running in our brains for 'free will' can be computationally irreducible in this way.…

I don't think this concept is helpful, honestly. If the brain is deterministic, then you would be able to fully simulate it in a regular von Neumann computer, and as a result you'd be able to predict someone's actions and choices with perfect accuracy, which leaves no space for any agency or "ghost in the machine".

Re: Does quantum theory imply the universe is preordained?

#173

Post by dotsam »

nwiswell wrote: post #172
dotsam wrote: post #86

Earlier quoted context omitted.

I find the idea of computational irreducibility useful for rescuing a type of free will in a fully determined world. Computationally irreducible programs are perfectly deterministic, yet you can't predict the output before you run them, and nor are there any shortcuts to get there before running them for the first time. The program running in our brains for 'free will' can be computationally irreducible in this way.…

I don't think this concept is helpful, honestly. If the brain is deterministic, then you would be able to fully simulate it in a regular von Neumann computer, and as a result you'd be able to predict someone's actions and choices with perfect accuracy, which leaves no space for any agency or "ghost in the machine".

How do you predict what the full simulation will do, before you run it for the first time? If it is computationally irreducible, then you can't predict the outcome - the only way to know what will happen is to run the computation and see what happens. And this computation, this full simulation, is a person with free agency. They are just running on a non-biological computational substrate.

Re: Does quantum theory imply the universe is preordained?

#174

Post by apatil »

FredPret wrote: post #96

I always see references to free will when certain people start talking about quantum mechanics. Why do people care if free will exists or not? It doesn't seem to affect anything I can think of. - It feels like it exists; it feels like I'm making my decisions. Even if my whole life is a series of decisions calculated by me in some inevitable way, the calculations still had to happen in my head, and the experience of d…

Penalizing a crime might make sense for the purpose of deterrence even if there is no conscious free will. The size of the deterrent effect is a scientific question, and how to weigh the benefits of deterrence to society vs. the harm the punishment inflicts on the criminal is a moral question (where by moral I mean "should we do this").

However, penalizing a crime for the purpose of retribution makes no sense if there is no conscious free will. The criminal's consciousness experiences the harm of the punishment, but didn't cause the actions that constituted the crime. This is patently unfair.

I don't think conscious free will exists. One of the reasons I care is that, if most people shared that belief, we would talk and think about crime so differently that our approach to crime would change in the direction of becoming more humane.

For example, given the news of SBF's conviction for fraud, no one would be happy about the fact that he will likely experience many years in prison. We might be happy that the harm his actions caused has been stopped, and we may feel a kind of dutiful satisfaction in the knowledge that the system is working to deter and prevent this kind of harm. However, these emotions would be tempered by regret that a young man is going to lose part of his life, and we would be questioning whether there's any way to achieve the same level of harm prevention without inflicting such serious harm on one person.

Re: Does quantum theory imply the universe is preordained?

#175

Post by nwiswell »

dotsam wrote: post #173
nwiswell wrote: post #172

Earlier quoted context omitted.

I don't think this concept is helpful, honestly. If the brain is deterministic, then you would be able to fully simulate it in a regular von Neumann computer, and as a result you'd be able to predict someone's actions and choices with perfect accuracy, which leaves no space for any agency or "ghost in the machine".

How do you predict what the full simulation will do, before you run it for the first time? If it is computationally irreducible, then you can't predict the outcome - the only way to know what will happen is to run the computation and see what happens. And this computation, this full simulation, is a person with free agency. They are just running on a non-biological computational substrate.

How can you have two persons with free agency that always make the same decision?

Or a hundred such persons?

The calculation itself may be irreducible, but what is the implication for consciousness and agency if, midway through the calculation, you fork the process? What about a quarter of the way, or three quarters?

Re: Does quantum theory imply the universe is preordained?

#176

Post by dotsam »

nwiswell wrote: post #175
dotsam wrote: post #173

Earlier quoted context omitted.

How do you predict what the full simulation will do, before you run it for the first time? If it is computationally irreducible, then you can't predict the outcome - the only way to know what will happen is to run the computation and see what happens. And this computation, this full simulation, is a person with free agency. They are just running on a non-biological computational substrate.

How can you have two persons with free agency that always make the same decision? Or a hundred such persons? The calculation itself may be irreducible, but what is the implication for consciousness and agency if, midway through the calculation, you fork the process? What about a quarter of the way, or three quarters?

Then you have n free and conscious agents! And yes, if their simulated environments were identical, then the copies would all make identical decisions (all the copies would still have the same conscious experiences of free will that you and I have).

Whilst this feels unsatisfactory, it is the only way I can see of talking about agency without invoking decision-making processes that disobey the laws of physics, or rely on randomness. And unless a supernatural version of free will appeals, I think this is the best kind of free will available: governed by rules, but nevertheless fundamentally unpredictable. The only other option would be to rely on complete randomness as a basis for decisions, which seems worse.

Re: Does quantum theory imply the universe is preordained?

#177

Post by nwiswell »

dotsam wrote: post #176
nwiswell wrote: post #175

Earlier quoted context omitted.

How can you have two persons with free agency that always make the same decision? Or a hundred such persons? The calculation itself may be irreducible, but what is the implication for consciousness and agency if, midway through the calculation, you fork the process? What about a quarter of the way, or three quarters?

Then you have n free and conscious agents! And yes, if their simulated environments were identical, then the copies would all make identical decisions (all the copies would still have the same conscious experiences of free will that you and I have). Whilst this feels unsatisfactory, it is the only way I can see of talking about agency without invoking decision-making processes that disobey the laws of physics, or rel…

I think philosophically when we talk about non-causal "free will" it is "not scientifically understood", but that's different than "supernatural".

Just because our perception prevents us from predicting outputs from inputs in a way that appears random does not mean that it is just a chaotic system. This is part of the question posed by the original article: does quantum theory provide certain mechanisms that could permit non-deterministic agents to intervene in causal ways that are not predictable? Or would we have to appeal to the supernatural / mystic / divine in order for such a thing to even be possible?

Certain interpretations (e.g., the "Many Worlds" interpretation of QM) are more conducive to this possibility than others.

Generally, "free will" is simply stated as "the freedom to do otherwise". Returning to the "simulated brain" example -- if the computer simulation is faster than the "squishy brain" agent, then it has already predicted the outcome, and the "squishy brain" agent has no "freedom to do otherwise": the outcome is pre-determined.

Re: Does quantum theory imply the universe is preordained?

#178

Post by dotsam »

nwiswell wrote: post #177
dotsam wrote: post #176

Earlier quoted context omitted.

Then you have n free and conscious agents! And yes, if their simulated environments were identical, then the copies would all make identical decisions (all the copies would still have the same conscious experiences of free will that you and I have). Whilst this feels unsatisfactory, it is the only way I can see of talking about agency without invoking decision-making processes that disobey the laws of physics, or rel…

I think philosophically when we talk about non-causal "free will" it is "not scientifically understood", but that's different than "supernatural". Just because our perception prevents us from predicting outputs from inputs in a way that appears random does not mean that it is just a chaotic system. This is part of the question posed by the original article: does quantum theory provide certain mechanisms that could pe…

> Certain interpretations (e.g., the "Many Worlds" interpretation of QM) are more conducive to this possibility than others.

> Generally, "free will" is simply stated as "the freedom to do otherwise".

In the Many Worlds interpretation, as I understand it, everything that can happen, does happen (as it would in a single universe of infinite extent). So no matter what you choose to do in one universe, the multiverse-wide outcome is predetermined: copies of you always make all choices not forbidden by the laws of physics.

I think this just pushes the problem of determinism out to the multiverse as a whole.

Re: Does quantum theory imply the universe is preordained?

#180

Post by Animats »

GoblinSlayer wrote: post #154
Animats wrote: post #94

No new info. From the article: "So how deterministic is the Universe? The answer will depend on the final theory that bridges the divide between quantum physics and relativity — and that remains a far-off prospect." Unless physics is totally noise-free, with zero randomness, there is indeterminism. There are so many chaotic processes that amplify randomness that any randomness at all will cause wide divergence in out…

Noise doesn't necessarily participate in reasoning, it can be just a factor to ignore or smooth out. You can calculate 1+1 at a random moment of time, but the result will be 2 - deterministic in spite of present randomness.

The reverse, however, is not true. If you have no source of randomness at all, you get the same answer every time.

"Anyone who considers arithmetical methods of producing random digits is, of course, in a state of sin." - Von Neumann

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