quarta-feira, 25 de abril de 2012

A Million Dollar Puzzle: The Newcomb Paradox


You are paying a visit to Perfect Predictions, the world's most accurate clairvoyancy agency, in the hope of hearing some good news about the imminent demise of your Great Aunt Maud. However, you arrive to find that your consultation has been cancelled - due to entirely foreseen circumstances, obviously - and instead you're asked to play a game that should net you a very large sum of money. You are told that the game has something to do with Newcomb's Paradox, though you're none the wiser for that.

The Game

The game has the following form. You will be presented with two boxes:

Box A will contain $10,000.
Box B will contain $1,000,000 or nothing.
You will not be able to see inside the boxes, so you won't know whether Box B contains $1,000,000 or nothing. You will then be given the choice between taking home both boxes or just Box B.

There are two crucial things to take into account when making your decision.

The amount of money in Box B will be determined by Perfect Predictions’s most accurate clairvoyant - for all intents and purposes, 100% accurate – on the following basis. If she predicts that you will take home both boxes, then no money will be put into Box B. If she predicts that you will take home only Box B, then $1,000,000 will be placed into the box.
The prediction will already have been made by the time the game starts, and the amount of money in Box B already fixed.

Assuming you want to win as much money as possible, should you take home both boxes or just Box B?

- I should take home both boxes
- I should only take home Box B