You are asked to choose between taking box A and taking both A and B, where B contains $1000, and A contains either $1 million (if a reliable predictor thought you would take only A) or $0 (if the predictor thought you would take both). Dominance reasoning supports taking both boxes, but expected utility maximization seemingly supports taking only A. The correct choice is both boxes. Expected utility should be calculated using a weighted average of the expected utility conditional on each possible assumption about how the unalterable parts of the external world are. This is because rational individuals seek to cause good outcomes, not produce evidence of good outcomes. This reconciles the expected utility principle with the dominance principle.
- Lewis, David. 1979. “Prisoners’ Dilemma Is a Newcomb Problem”, Philosophy & Public Affairs 8: 235–40.Google Scholar