In 1969, the game theorist John Harsanyi wrote an article criticizing the two main postulates of the general theory of social behavior prevalent at the time: the functionalist approach to the explanation of social institutions and the conformist approach to the explanation of individual behavior. According to Harsanyi, functionalist and conformist theories overstated the degree of consensus in societies, could not account for change, and described observed behavior without explaining it. Harsanyi proposed an alternative approach provided by theories based on the concept of rational choice (rational behavior, or rational decision-making). His goal was to develop a hypothetico-deductive theory explaining (and possibly predicting) a large number of empirical facts from a few relatively simple theoretical assumptions or axioms. Among students of international politics, Harsanyi’s approach sparked a controversy about rationalism. However, some critics of rationalism do not distinguish clearly between the interest-based theories Harsanyi criticized and the rational choice methods he advocated, and some even confuse both with neoclassical economics. In order to understand the issues raised in the controversy about rationalism, it is helpful to look at interest-based theories of politics and their relation to neoclassical economics. Game theory has provided a useful framework for the intellectual agenda outlined by Harsanyi, especially in the area of international security.
Justice as a Natural Phenomenon