Is rational choice humanity’s most distinctive trait?

The Greeks and the thinkers of the Enlightenment regarded reason as the defining quality of humankind. The Utilitarians limited it to the selection of means to any given end for action excluding the determination of moral values and social institutions. This became a postulate of classical and neoclassical economics borrowed by rational choice theory in sociology. James Coleman accepted as rational any action based on the actor's belief in its rationality, which would not rule out the delusions of psychotics. Despite this and other concessions that treat almost any explicable action as rational, sociologists have correctly criticized rational choice theory for ignoring the pervasive effects of socialization in achieving the internalization of norms and values. Rational choice theory also fails to illuminate human emotions and motivations, pictured in their full complexity in great literature.