The prisoner’s dilemma
In each round, choose to cooperate or to defect. What you win also depends on your opponent’s choice.
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Try the experiment: your result will appear here, next to what most people do.
What just happened (read it after the experiment)
What most people do: In experiments, most people cooperate at first, then copy their opponent.
If you defect against a cooperator, you win big; if you both cooperate, you both do well; if you both defect, you both get little. In a single round, defecting always seems rational.
But when you play several times, everything changes. In 1980, Robert Axelrod organized a tournament between computer programs: the winning strategy was the simplest one, “tit for tat”: cooperate first, then copy the other player’s last move.
Cooperation doesn’t require kindness: it’s enough to meet again.
More experiments
Sources
- Robert Axelrod, The Evolution of Cooperation, 1984.