Rational Choice Epistemology and Belief Formation in Mass Politics

This paper begins with a general discussion of the epistemology of rational choice, and argues that there are important questions in political science for which rational choice theory is not a particularly useful epistemic tool. It is further argued that part of the problem lies with the particular vision of methodological individualism that is inherent in the use of classical rational choice assumptions in game theoretic models. An alternative approach that endogenizes the way in which people form beliefs is then advocated as a potential solution to this problem, both as a means to expand the substantive reach of optimizing theories in political science, as well as a way of incorporating more psychological realism into models of political behavior. Two novel models allowing actors within political contexts to form beliefs in endogenous ways are then presented and discussed. ERIC DICKSON is Assistant Professor in the Department of Politics at New York University. His main research interests include the behavioral foundations of game theory, mass political behavior, and social science experiments. ADDRESS: Department of Politics, New York University, 726 Broadway, Room 744, New York, NY 10003-9580, USA [email: [email protected]] ∗I wish to thank Jim Alt, Bob Bates, Ethan Bueno de Mesquita, James Fowler, Catherine Hafer, Dimitri Landa, Becky Morton, Ken Scheve, and Ken Shepsle, as well as participants at the Epistemologies of Rational Choice conference, for useful and stimulating conversations related to the ideas contained in the paper. I also thank the anonymous reviewers for their helpful suggestions. Earlier drafts of this paper were under the title “Methodological Individualism, Mass Politics, and Rational Choice Epistemology.” 1 Rational Choice Epistemology and the Study of Beliefs When asked to describe the methodology of his field, a nuclear physicist once said, “we learn about the structure of nuclei by smashing them together and seeing what happens.” In this spirit, the study of politics might reasonably be deemed the nuclear physics of the social sciences – politics is much of “what happens” when individuals with divergent interests are thrown together and compelled to make collective decisions about the allocation of power and the distribution of scarce resources in their societies. But there are, of course, many differences between nuclear physics and rational choice political science; one important difference is an epistemological one, concerning the types of inference typically made in the two fields. The epistemology of experimental nuclear physics generally involves learning about the structure of nuclei based on observations made in the aftermath of nuclear collisions. Such learning takes place by deducing the different macro-level consequences of alternative, and distinguishable, micro-level possibilities, and then observing which macro-level consequences are actually realized when the objects of study (nuclei) are exposed to different experimental treatments (smashed together in various combinations and in different ways). Various inferences about the structure of nuclei are then made based on which macro-level consequences have been observed. In short, the fundamental goal is to further understanding of the subject’s microfoundations. The epistemology of rational choice in positive political theory involves learning of a very different kind. Typically, positive rational choice models seek to explain, or at least to provide a mechanism for or an account of, macro-level phenomena.1 What might be considered the microfoundations of political science – the cognitive pathways through which individual members of society form political judgments, learn about political questions, or come to make political choices – are generally not the objects of interest for rational choice political theorists. Instead, these aspects of human nature are stipulated by assumption, almost always in the form of standard decision theoretic axioms. Investigation of these microfoundational questions is generally left as an exercise for another field – psychology, perhaps, or the behavioral branch of political science – to the extent that rational choice theorists conceptualize it as a task at all. Indeed, substantial