Homo Economicus and Zoon Politikon: Behavioral Game Theory and Political Behavior

The rational choice model pioneered by economists is rapidly becoming the standard approach throughout the behavioral sciences. The model is attractive as it allows the mathematical formalization of an essential truth, namely that when people act, they are generally trying to accomplish something, and their efforts are more or less effectively oriented to this end. However, its acceptance in other disciplines coincides with an increasing recognition in economics of the limitations of the behavioral assumptions sometimes summarized by the term Homo economicus. While Homo economicus is not entailed by any of the axioms of the rational choice model, in both teaching and research three assumptions embracing this behavioral model are commonly treated as integral to the approach. First, preferences are assumed to be outcome-regarding; i.e., agents care about only the quantity and quality of goods and services that they possess and consume, not about the social process through which their economic opportunities are determined. In fact, preferences are also in part process-regarding; agents care about how they treat and are treated by others. In evaluating states, people care how those states come to be available. In particular, people care about fairness and reciprocity. Second, preferences are assumed to be self-regarding: agent are assumed to care only about states experienced by themselves, not by others. In fact, however, preferences are in part other-regarding; agents care about the well-being of others, both positively and negatively. In particular, people reward and punish the behavior of others even at a net cost to themselves. ∗Affiliations: Bowles, University of Siena and Santa Fe Institute; Gintis, Santa Fe Institute and Central European University, Budapest. We would like to thank Robert Goodin, Charles Tilly, and Elisabeth Wood for comments, as well as the John D. and Catherine T. MacArthur Foundation and the Behavioral Sciences Program of the Santa Fe Institute for financial support.