A Problem You'll Never Solve

Newcomb’s Paradox has confounded philosophers, mathematicians, and game players for over 50 years. The problem is simple: You can take Box A, which contains $1,000, *and* Box B, which contains either $0 or $1,000,000, or you can just take Box B. The right choice seems obvious -- but there’s a catch.

Before you play, an omniscient being has predicted whether you’d take both Box A and Box B or *only* Box B. If he’s predicted that you’ll take both, he’s put $0 in Box B. If he predicts that you’ll only take Box B, he’s put $1,000,000 inside. So… what do you do?

I explore the two approaches to this problem, one based on the math of expected utility and the other based on a logical dominance principle. Newcomb’s Paradox raises questions about free will and determinism as it explores whether a problem with no solution might be easier than a problem with two perfectly valid contradictory solutions.

*** SOURCES ***

“Newcomb's Problem And Two Principles Of Choice,” by Robert Nozick

Newcomb’s Paradox poll results from The Guardian:

*** LINKS ***

Grandayy Links

Vsauce2 Links

Hosted, Produced, And Edited by Kevin Lieber

Research And Writing by Matthew Tabor

Huge Thanks To Paula Lieber

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MY PODCAST -- THE CREATE UNKNOWN

[evancunningham]

Me: Yes, obviously both
Kevin: A magical genie predicted that and makes B worth 0
Me: That seems like it was an important part of the setup

[Henchman]

I choose box A. I'm not interested in the Genie's bullsh1t.

[thepurityofchaos]

*Chooses only box A*

Genie: Wait, that's illegal

[NA-nzlv]

it's kind of a flawed question though, right? It really depends on how smart the genie is, if he is omniscient then choosing the second box is always the best choice.

[yonatanmoritz]

Kevin the type of guy to actually count out 1000 candies.

[that_random_dude]

I choose only box A. There is clearly not enough room for 1, 000, 000 candy in box B!

[AngeK]

Kevin: Will you choose box B or both boxes?
Me: Both
Kevin: Now let me introduce the genie
Me: well fu too then

[BainesMkII]

The only reason there is a question of which to take is because the presenter keeps changing the rule for how the contents of the mystery box are determined. At first, it is implied to just be independent of the player. Then it is change to be a genie that bases the contents off of what he believes the player will pick, which is no longer truly independent. But when the viewer gets pushed towards the idea that it is best to take only the mystery box, the presenter starts pushing that the mystery box was determined long ago. Then out of nowhere the presenter introduces the idea that the genie is only right 90% of the time. If you keep changing the rules to suit your purpose, you can make any problem into "a problem you'll never solve".

[sherryy]

The problem is that original question contains no information about a genie.

[jwmmitch]

"B only" seems based on trusting the genie can make an accurate prediction while "both" seems based on trusting the genie can't actually predict the future.

[wilsonleddy]

The real question is, why would I really need 1, 000, 000 candies.

[ChristophelusPulps]

"This question is actually a lot less simple than it seems... because here are completely game-changing additional parameters I didn't mention before." Eye roll.

[stevehouser]

How can we make the right choice when you keep adding new conditions

[VoxSpark]

Kevin: you will take both boxes right?

Me: *knowing kevin* WRONG
Kevin: RIGHT
Me: right?
Kevin: Wrong

[oranjethefox]

The issue with strategic dominance in this scenario is that it has a fixed view of time, whereas in this situation, your choice has some effect on what is in the mystery box despite the contents already being decided.

[politicallycorrect]

Both. Choosing only box B has a possible outcome of $0. Taking both has a minimum outcome of $1000. I'm not gonna deal with a Genie for free.

[polygondwanaland]

Take only box A. Confuse and disturb the Basilisk.

[HisWattson]

I'm taking both boxes literally every time

[deedevon]

The problem is also that it’s never really made clear if the participant *knows* about the genie’s powers, or if the scenario is presents as it was in the first bit of the video. And if you know, can you outsmart the genie by thinking really hard about choosing one option and then switching suddenly? Can you mind-battle the genie? Or are you unaware of the genie the whole time?

[blackbull]

11:00 Genie's a freakin' liar, he put 18 candies inside the mystery box