Despite his outstanding empirical work and his exceptional clarity as a theorist of collective choice, James S. Coleman's program for social science would take it in the wrong direction. Whatever else it does, social science must explain social processes. Coleman: 1) neglected to specify causal mechanisms, 2) promoted an incomplete and therefore misleading psychological reductionism, and 3) advocated a form of general theory—rational choice analysis—that cannot, in principle or in practice, provide adequate explanations for the great bulk of social processes.