The Structure and Evolution of Morality in H. Sapiens* Herbert Gintis Santa Fe Institute and Central European University *Adapted from The Bounds of Reason: Game Theory and the Integration of the Behavioral Sciences (Princeton University Press 2009) and (with Samuel Bowles) A Cooperative Species: Human Reciprocity and its Evolution (forthcoming).

Disarray of the Behavioral Sciences The behavioral sciences (biology, economics, sociology, anthropology, psychology, political science) are in profound disarray, with incompatible models of human behavior across disciplines. We now have the analytical and empirical basis for beginning to construct an integrated behavioral science.

Models of Human Choice and Strategic Interaction are Incompatible across Disciplinary Boundaries Economics: Homo economicus, the self-regarding maximizer with unlimited and costless information processing capacity, who acts prosocially when the incentives align with self-regarding motives. Sociology: Homo sociologicus, the prosocial actor.

Morality is an Evolved Human Capacity While there are precursors in other social species, humans are the only known species in which individuals are genetically predisposed to perceive and respond to socially constructed social conventions and norms. Human morality has a broad universal component (see Donald Brown, Human Universals (1991). Human morality is supported by a highly evolved array of universal social emotions, including shame, empathy, taste for reciprocity, pride, jealousy, love, and guilt. The human condition is the result of gene-culture coevolution.

Moral and Linguistic Systems Morality is similar to language: in both moral and linguistic systems (a) there is correct and incorrect behavior; (b) the rules are considered ‘right’ and their violation is considered ‘wrong’; and (c) there is a basic commonality among all moral systems, as among all languages, but there is considerable variation in the content of moral systems and the grammar and vocabulary of languages. Human societies are complex, dynamical, adaptive, nonlinear systems, of which morality is an emergent property. Moral systems have a life and dynamic of their own, and may either support or oppose the reproduction of the dominant social institutions.

Moral Values are Objects of Desire Choice and strategic interaction are best modeled using the rational actor model, also known as the ‘preferences, beliefs, and constraints’ (PBC) model. Moral values are arguments in the individual’s preference function, and hence are traded-off against each other and against non-moral interests in the way depicted in economic consumer theory. We can discover the content and strength of moral values through behavioral game theory, under controlled laboratory and field conditions.