The Rational Analysis of Human Cognition*

Abstract Rationality appears basic to the understanding of mind and behaviour. In practical decisions, such as whether a person is morally responsible for his or her actions, to whether a person can be hospitalized without consent, it seems crucial to be able to draw a boundary between sanity and madness, between rationality and irrationality. In economics, and increasingly, other areas of social science, human behaviour is explained as the outcome of ‘rational choice’, concerning which products to buy, whom to marry, or how many children to have (Becker 1975, 1981; Elster 1986). But rationality assumptions go deeper still—they are embodied in the folk psychological style of explanation in which we describe each other’s minds and behaviour (Fodor 1987; Stich 1983).