prisoners dilemma


prisoners’ dilemma

a paradigm case in the THEORY OF GAMES, in which two prisoners, against whom there is some evidence of a crime but not enough to convict and who cannot communicate with each other, are each promised a light sentence if one of them confesses and the other, who would then be given a severe sentence, does not. If both confess they are promised a moderate sentence, but if neither confesses then both will receive a light sentence. The case this illustrates is the non-ZERO-SUM GAME, since there is no single ‘rational’ outcome. If neither confesses, both gain more than if both confess, but by not confessing they risk the most severe of the three possible penalties which will be imposed if only one confesses. Like all such hypothetical examples in game theory, the suggestion is that such models illuminate situations in the real world (even if they do not exactly match them). see also FREE RIDER.