SOCIAL CHOICE THEORY

Social choice theory studies the aggregation of individual preferences, utilities, or other attributes into a social preference or choice function. This chapter provides an overview of social choice theory and its applications to moral, social, and political philosophy. Topics include Arrow’s impossibility theorem, Sen’s framework of social welfare functionals, Harsanyi’s arguments for utilitarianism, non-welfarist criteria such as liberty and fairness, the doctrinal paradox of judgment aggregation, the strategic manipulability of voting procedures, and the properties of majority rule. We also examine the philosophical assumptions of Arrow’s framework and the implications of social choice theory for fundamental questions in democratic theory.