When 3-year-olds pass the appearance--reality test

Sixty-eight 3-year-olds received a standard appearance-reality task along with either a trick task, in which the appearance question was placed in the context of a deceptive game, or a reduced information processing task, in which a dual object (e.g., a sponge-rock) was presented along with an object that matched the dual object's identity (a sponge) and one that matched the dual object's appearance (a rock). Children were more likely to pass either the trick or reduced information processing task and fail the standard than the reverse. Thus, 3-year-olds can grasp the distinction between appearance and reality (a) when their goal is to trick someone, which may prime them to think about the other's mental state, and (b) when they do not need to held conflicting object identities in mind at the same time.