Three studies (N = 171) examined preschool children's tendency to use category information to make inferences about ambiguous behavior. Children heard stories in which category information about story characters was manipulated and behavioral information was held constant. Participants were asked to evaluate, explain, and determine the significance of the behavior in question. Children tended to be harsher judges of the same ambiguous behaviors when performed by (a) humans as compared to animals, (b) boys compared to girls, and (c) older children compared to younger children. Results suggest that young children hold differentiated notions of the mental states and dispositions that underlie behavior and that these notions vary as a function of category membership. These findings support the conclusion that even young children can hold and use multiple folk psychologies. (Contains 3 tables.)