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Newcomb's Paradox Needs a Demon

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Re: Newcomb's Paradox Needs a Demon

#21

Post by mcphage »

genshii wrote: post #18

I've been presented with this thought experiment before and I always feel like I'm missing something when other people talk about it. Why would you ever take both boxes? The premise is that the predictor is always right. So whether you take one or both boxes, the predictor would have predicted that choice. We know from the setup that if the predictor said you would take the one box, it will have a million dollars. Th…

> Why would you ever take both boxes?

As near as I can tell, it boils down to this: no matter what the predictor has chosen, one you walk into that room, there's more money in both boxes, then there is in one box.

But it feels like half an analysis—focusing solely on what you decide, while ignoring the fact that the other side is deciding based on what you think they'll decide.

Maybe that's me being unfair, because I'm a solid one boxer.

I also disagree with the linked article—I don't think it matters at all how the predictor makes their decision, because the outcome really doesn't matter if it's 100% accurate or 99% accurate. Or even like, 80% accurate. There's no magic required for the experiment to work.

Re: Newcomb's Paradox Needs a Demon

#22

Post by bennettnate5 »

Here's a potential winning strategy: take a coin out of your pocket and flip it 100 times. If it lands heads 51 or more times, take both boxes; otherwise, just take the one. Provided the computer had anticipated you being the kind of person that would do this, it would anticipate you are probabilistically more likely to take the single box exclusively and put the million dollars in it. Regardless of the outcome of the coin tosses, you get that million dollar box, and you still get the added $1000 in the first box 49% of the time.

Re: Newcomb's Paradox Needs a Demon

#23

Post by vidarh »

malfist wrote: post #12
vidarh wrote: post #9

Assuming I have no way of testing the predictor, my decision would be to pick both boxes on the basis that $1000 is not a lot of money to me, but $1000000 is, and I wouldn't worry about the odds, because without knowing the nature of the specific predictor we're down to Pascal's Wager married to the Halting Problem: We don't know whether or how our actions and thought processes processes might affect the outcome, and…

Two boxes is the only choice that makes sense. It is always better than one box. No matter what you do after you enter the room, the predictor has already made their move, nothing you do now will change it. The only logical thing to do is to take both boxes because whatever the value in the second box is it will be added to the first box. If you only take the second box you are objectively always giving up $1,000 and…

Too late to edit my original comment now, but my intent was actually to make the argument for picking one, hence my comment on not caring much about the $1000.

If the predictor is indeed flawless, or almost flawless, if I were to be the type of person likely to pick both boxes, the opaque box would almost certainly be empty. So the winning strategy is not just picking the opaque box, but being the kind of person likely to pick the opaque box only.

You're right that what I do after I enter the room is irrelevant if it is somehow independent of what I have done before. But it can't be independent of what I did before if the predictor is flawless. If the predictor is flawless, then either my actions needs to be deterministic so that it can in fact know what I will do when in the room, or the predictor is supernatural and can know or cause me to act in a certain way for that reason.

Either way, giving any indication that you'd pick both boxes would be a bad idea (so I guess my typo above might screw me over if ever presented with this choice).

Re: Newcomb's Paradox Needs a Demon

#24

Post by vidarh »

arethuza wrote: post #11
vidarh wrote: post #7

Earlier quoted context omitted.

I agree with you that it doesn't require that you are in a simulation, but a flawless predictor would be a strong indication that a simulation is possible , and that should raise our assumed probability that we're in a simulation.

I would think that the existence of a flawless predictor is probably more likely to indicate that memories of predictions, and any associated records, have been modified to make the predictor appear flawless.

I would say that if we presume memories of everyone involved have been modified, that is an equally strong predictor that we are in a simulation.

Re: Newcomb's Paradox Needs a Demon

#25

Post by vidarh »

mcphage wrote: post #21
genshii wrote: post #18

I've been presented with this thought experiment before and I always feel like I'm missing something when other people talk about it. Why would you ever take both boxes? The premise is that the predictor is always right. So whether you take one or both boxes, the predictor would have predicted that choice. We know from the setup that if the predictor said you would take the one box, it will have a million dollars. Th…

> Why would you ever take both boxes? As near as I can tell, it boils down to this: no matter what the predictor has chosen, one you walk into that room, there's more money in both boxes, then there is in one box. But it feels like half an analysis—focusing solely on what you decide, while ignoring the fact that the other side is deciding based on what you think they'll decide. Maybe that's me being unfair, because I…

Even if it's 50% accurate the benefit of picking both is marginal. If it's 50% accurate and you pick both boxes, 50% of the time you get nothing, 50% of the time you get 0.1% more. So unless you know that the predictor is worse than chance, you at worst suffer a meaningless loss if you pick one box.

Re: Newcomb's Paradox Needs a Demon

#26

Post by vidarh »

ordu wrote: post #6
danbruc wrote: post #2

The existence of a flawless predictor means that you do not have a choice after the predictor made its prediction, the decision must already be baked into the state of the universe accessible to the predictor. It also precludes that any true randomness is affecting the choice as that could not be predicted ahead of time. I do not think that allowing some prediction error fundamentally changes this, it only means that…

> Which also renders the entire paradox somewhat moot because there is no choice for you to be made. Not quite. You did choose your decision making methods at some point in your life, and you could change them multiple times till you came to the setup of Newcomb's paradox. If we look at your past life as a variable in the problem, then changing this variable changes the outcome, it changes the prediction made by the…

This is a compatibilist view. However, we can tell that most people don't adhere to a compatibilist view of free will because it tends to make people very upset if you suggest they have no "genuine" free will or agency, and the moral implications behind the assumption of genuine agency are e.g. baked into everything from our welfare systems to our justice systems, that assumes people have an actual choice in what they do.

For that reason I strongly disagree with the compatibilist view - language is defined by use, and most people act in ways that clearly signal a non-compatibilist view of free will.

Re: Newcomb's Paradox Needs a Demon

#27

Post by GaelFG »

xigoi wrote: post #20
GaelFG wrote: post #14

I don't get the 'choice' : the content of the box is aldready defined when you take your decision so taking it won't change the content of the black box and the open/transparent box have no drawback. What am I missing ?

Assuming that the predictor is always right, there are only two possible scenarios: • You take one box and get $1000000 • You take two boxes and get $1000 The choice seems quite clear to me.

Not from the article : Before you walk in, a supercomputer predicted which choice you'd make, and put $1000000 in the opaque box if it predicted you'd take just the one, or $0 if it predicted you'd take both.

So the amount of money in the black box don't change whatever you REALLY pick. Either the predicator would have guessed you'd pick both and there is 0$ in black box, in that case you have interest to take both boxes and win $1000 which is better than zero.

Or it predicted you would only take the black box, put $1000000 in it and then again you win more by taking the two boxes.

Re: Newcomb's Paradox Needs a Demon

#28

Post by ordu »

vidarh wrote: post #26
ordu wrote: post #6

Earlier quoted context omitted.

> Which also renders the entire paradox somewhat moot because there is no choice for you to be made. Not quite. You did choose your decision making methods at some point in your life, and you could change them multiple times till you came to the setup of Newcomb's paradox. If we look at your past life as a variable in the problem, then changing this variable changes the outcome, it changes the prediction made by the…

This is a compatibilist view. However, we can tell that most people don't adhere to a compatibilist view of free will because it tends to make people very upset if you suggest they have no "genuine" free will or agency, and the moral implications behind the assumption of genuine agency are e.g. baked into everything from our welfare systems to our justice systems, that assumes people have an actual choice in what the…

I personally don't see any problems with this. For example, in most cases we can agree if someone had free will or no when they committed a crime. Even if I prefer compatibilist view and you are not, we'll agree in the most cases. In the cases when we may not agree the reasons of disagreement will not stem from this fundamental disagreements, but from things like should we treat state of affect as a state when a human has no free will.

So, a compatibilist view is not incompatible with the world we live in, but moreover, it is needed to keep our world functioning. The world we live in is mostly artificially constructed. Welfare and justice systems are not "genuine", they are artificial constructs. They play a role in our society and the ideas of "free will" and "guilt" are constructed also, and they are tweaked to make our systems to work better. If you assume that free will and guilt are "genuine" or God given, then you can't tune them to better match their purposes. You are losing agency this way, losing part of your free will, you can't consciously and reasonably discuss if state of affect should be an exception from the rule "any person has a free will". You'll be forced either to skip the discussion, or to resort to some kind of theological arguments.

But if you accept, that "free will" is a social construct, then you can easily identify the affected variables: it is all about punishment for crimes or awarding people for their pro-social deeds. You can think of how "state of affect inhibits free will" can influence all these goals, you can think of the possibility of people simulating state of affect (or even nurturing their personal traits that increase the probability of entering state of affect) to avoid a punishment. You can think rationally, logically and to pick a solution that benefits the society the best. Those very society with baked in idea of free will. Or you can choose to believe "free will" is God given, because of an irrelevant linguistic argument, and lose the ability to make our world better.

> most people act in ways that clearly signal a non-compatibilist view of free will.

Of course, we are not living in quantum mechanics we live in a world that is constructed by people. I mean, all this is built on top of QM, but QM laws do not manifest themselves directly for us. We have other explanatory structures to deal with everyday physics. But even physics doesn't matter that much: I turn the switch and voila I have light, and the heck with conservation of energy. I can talk to you, despite we are residing on different continents, 1000s of km don't matter. If I want to eat I do not try to kill some animal to eat it nor do I gather seeds and roots in a wild to eat them. I go to work and do something, get my salary and buy food in a local store. We are living in an artificial world with artificial rules. Free will is part of this world. Of course we talk about it like it exists. We talk about it like it is a universal truth. Relativity I mentioned above doesn't show itself most of the time, because the world is constructed in a way, when we can agree about someone having it. Situations when this is not the case are very strange and can be even punished: manipulation (which is come close to taking people's agency away from them) is deemed amoral.

The world constructed so we can ignore that free will is just an illusion, moreover it is constructed to think about it in terms of free will, so you'll have issues thinking about it in other terms. Like you'll have a lot of issues trying to calculate aerodynamic of a plane relying on equations of quantum mechanics.

Re: Newcomb's Paradox Needs a Demon

#29

Post by malfist »

OskarS wrote: post #15
malfist wrote: post #12

Earlier quoted context omitted.

Two boxes is the only choice that makes sense. It is always better than one box. No matter what you do after you enter the room, the predictor has already made their move, nothing you do now will change it. The only logical thing to do is to take both boxes because whatever the value in the second box is it will be added to the first box. If you only take the second box you are objectively always giving up $1,000 and…

> Two boxes is the only choice that makes sense. It is always better than one box. Congratulations on your $1,000. I'll use some of my $1,000,000 I got by nonsensically picking one box to toast in your honor and dedication to logic.

Or your zero dollars if your predictor wasn't quiet as perfect as billed.

Re: Newcomb's Paradox Needs a Demon

#30

Post by vidarh »

ordu wrote: post #28
vidarh wrote: post #26

Earlier quoted context omitted.

This is a compatibilist view. However, we can tell that most people don't adhere to a compatibilist view of free will because it tends to make people very upset if you suggest they have no "genuine" free will or agency, and the moral implications behind the assumption of genuine agency are e.g. baked into everything from our welfare systems to our justice systems, that assumes people have an actual choice in what the…

I personally don't see any problems with this. For example, in most cases we can agree if someone had free will or no when they committed a crime. Even if I prefer compatibilist view and you are not, we'll agree in the most cases. In the cases when we may not agree the reasons of disagreement will not stem from this fundamental disagreements, but from things like should we treat state of affect as a state when a huma…

A compatibilist view, to me, is usually immoral, because it seems to maintain the pretence of agency while admitting it's an illusion, and so persist in accepting treating people as if they have agency.

People who at least genuinely believe in free will and agency has an excuse if they e.g. support punishment that is not strictly aimed at minimising harm including to the perpetrator. A compatibilist has no excuse.

It is of course possible to hold a compatibilist view and still argue we should restructure society to treat people as if they do not have agency, but then the point on holding onto the illusion drops to near zero.

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