Collective,universal, and joint rationality

Rationality’s extension from individuals to groups yields collective rationality. Just as individuals should be rational, groups should be collectively rational. This paper briefly presents collective rationality and then compares it to universal rationality and joint rationality. Universal rationality is the rationality of all members of a group. It directs individualistic evaluation of a collective act. Joint rationality is the rationality of each individual’s part in a collective act given the collective act’s realization. Game theory uses it to characterize solutions to games. Collective rationality is not the same as either universal or joint rationality. However, in certain ideal conditions collective rationality agrees with universal rationality, and in other ideal conditions it agrees with joint rationality. Distinguishing the three types of evaluation and explaining their relations contributes to a general theory of rationality.