During the twentieth century, the ideas of Mandeville, Smith, and many others have been developed and systematized into what is now known as “the theory of rational choice.” The core of the theory is the postulate that people—“agents”—behave in such a way as to maximize their “utility function.” In principle, the utility function could be almost anything, but in practice almost all applications of the theory in the mainstream economics equate utility with material self-interest. In the most basic
