Liberty, Preference Satisfaction, and the Case against Categories

This chapter applies a distinction due to Broome between categorical and comparative formulations in ethics to social choice theory, using the Sen result on the 'impossibility of a Paretian Liberal' as a case study. The point of departure is the observation that the normative element within social choice theory is contained in the various criteria that any 'aggregation mechanism' must meet, rather than in terms of measures of the degree to which various desirable attributes (Paretianism, transitivity, non-dictatorship, and the like) are secured. The Sen result is a useful case because preference satisfaction and liberty are concepts that lend themselves to formulation in terms of 'degrees of achievement'. Indeed, Sen himself talks of his 'liberal' criterion as embodying 'minimal liberty'. Reformulating Sen's claims as exposing a possible tension between liberty and preference satisfaction invites comparison with other writers concerned with similar issues-and specifically with the work of Ronald Coase on social cost.