Categories influence predictions about individual consistency.

Predicting how people will behave in the future is a critical social-cognitive task. In four studies (N = 150, ages preschool to adult), young children (ages 4-5) used category information to guide their expectations about individual consistency. They predicted that psychological properties (preferences and fears) would remain consistent over time after hearing one example in which properties followed a category-linked distribution (e.g., children of different genders had different properties) but not when properties varied within a category (e.g., children of the same gender had different properties). The developmental course of these findings is examined. Results suggest the importance of considering how children's emerging theories of behavior and of social groups operate together to inform their expectations about the social world.