Dreier shows how the formal apparatus of decision theory is connected to some abstract issues in moral theory. He begins by explaining how to think about utility and the advice that decision theory gives us, in particular, decision theory does not assume or insist that all rational agents act in their own self-interest. Next he examines decision theory’s contributions to social contract theory, with emphasis on David Gauthier’s rationalist contractualism. Dreier’s third section considers a reinterpretation of the formal theory that decision theorists use: utility might represent goodness rather than preference. His last section discusses Harsanyi’s Theorem.