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Newcomb's Paradox Needs a Demon

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Re: Newcomb's Paradox Needs a Demon

#11

Post by arethuza »

vidarh wrote: post #7
danbruc wrote: post #5

Earlier quoted context omitted.

A flawless predictor would indicate you’re in a simulation [...] No, it does not. Replace the human with a computer entering the room, the predictor analyzes the computer and the software running on the computer when it enters. If the decision program does not query a hardware random source or some stray cosmic particle changes the choice, the predictor could perfectly predict the choice just by accurately enough emu…

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.

Re: Newcomb's Paradox Needs a Demon

#12

Post by malfist »

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 getting no value in exchange for doing so (since not taking the first box doesn't change what's in the second)

Re: Newcomb's Paradox Needs a Demon

#13

Post by Smaug123 »

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…

And for you, of course, that's true! Because you are the sort of being who two-boxes, and this fact is visible to the predictor. Other types of being can do better.

Re: Newcomb's Paradox Needs a Demon

#14

Post by GaelFG »

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 ?

Re: Newcomb's Paradox Needs a Demon

#15

Post by OskarS »

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…

> 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.

Re: Newcomb's Paradox Needs a Demon

#16

Post by gradschool »

I don't know about y'all, but this paradox was resolved to my complete satisfaction in a blog post some years ago, I believe by Scott Aaronson, though I can't find the link. If the predictor has such a good success rate, then it must be simulating people's brains, but since it's not always right, the simulation isn't perfect. The best strategy for playing this game therefore is to look for indications as to whether I'm the real me or the simulation when the question is posed to me, and choose accordingly. Am I floating in a sensory deprivation tank being asked my choice by a disembodied voice with no recollection of how I got there and no memory of my childhood? In that case maybe I'm the simulation, so my answer is that I'll choose just one box. Is it an ordinary day of my life and a plausible setting with all of my faculties and recollections intact? Then I'll assume simulated me had my back and take both boxes.

Re: Newcomb's Paradox Needs a Demon

#17

Post by djoldman »

For folks reasoning through the "paradox," this may be helpful:

https://arxiv.org/pdf/0904.2540

Abstract:

> ...We show that the conflicting recommendations in Newcomb’s scenario use different Bayes nets to relate your choice and the algorithm’s prediction. These two Bayes nets are incompatible. This resolves the paradox: the reason there appears to be two conflicting recommendations is that the specification of the underlying Bayes net is open to two, conflicting interpretations...

Re: Newcomb's Paradox Needs a Demon

#18

Post by genshii »

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. Therefore, if you take the one box it will have a million dollars in it (because whatever you choose is what the predictor predicted).

As an aside, I think whatever this says about free will or if you're actually making a "choice" is irrelevant in regards to if the million dollars is in the box. The way I see both choices is this:

You "decide" to take both boxes -> the perfect predictor predicted this -> the opaque box has zero dollars -> you get a thousand dollars

You "decide" to take the opaque (one) box -> the perfect predictor predicted this -> the opaque box has a million dollars -> you get a million dollars

If you want to consider the version of this where the predictor is almost perfect instead of truly perfect, I don't think that changes anything. Say it's 99% accurate or even 90% accurate.

You take the opaque box -> the predictor has a 90% chance of predicting this -> it follows that there's a 90% chance that the box has a million dollars -> you have a 90% chance of getting a million dollars

Had you picked both boxes, you have a 90% chance of not getting the million.

Re: Newcomb's Paradox Needs a Demon

#19

Post by imtringued »

I can't get behind this paradox, because the setup is too contrived and complicated.

I'd take the $1000 box without the second box just to mess with the computer.

Free money scenarios are always suspect so why would you ever expect to get a million dollars out of one?

Re: Newcomb's Paradox Needs a Demon

#20

Post by xigoi »

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.

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