Hard
Genius Level Riddles
13 XP

The Newcomb Problem

24,252 solved 74% solve rate 26% fail rate
A predictor (always right) puts $1000 in box A. Box B has $1M or $0 based on prediction. If it predicts you take only B, B has $1M. If it predicts you take both, B is empty. Do you take just B or both?
Only 74% solve this correctly
24,252 attempts
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Quick Answer & Explanation
One-boxers take only B

The answer to this riddle is One-boxers take only B. Difficulty: Hard · Solved by 24,252 puzzle lovers.

One-boxers take only B ($1M because the predictor is always right). Two-boxers take both (dominance argument). No consensus exists.
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