... years.¹

Actually, they didn't go to jail. When they were in court, and heard that they had both turned state's witness, they strangled each other. But that's another story.

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... situation.²

Actually, there were two tournaments. Their rules and results are described in Axelrod's book The Evolution of Cooperation.

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... rules:³

Actually, there is no universal definition for the multi-player prisoner's dilemma. The constraints used here represent one possible version of the three-player prisoner's dilemma.

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