Fuzzy preferences and social choice

Abstract The traditional Arrowian framework assumes that the aggregation rule maps n -tuples of exact individual preferences into an exact social preferences relation. In this paper, both individual and social preferences are permitted to be fuzzy . Under a relatively strong transitivity condition, the fuzzy counterparts of Arrow's conditions result in oligarchic and not dictatorial aggregation rules. The disctatorship result is restored if these conditions are supplemented by Positive Responsiveness. Under a weaker transitivity condition, these impossibilities disappear. However, if the social preferences relation is constrained to generate exact social choice, new impossibilities may emerge.