A prominent part of everyday thought is thought about mental states. We ascribe states like desire, belief, intention, hope, thirst, fear, and disgust both to ourselves and to others. We also use these ascribed mental states to predict how others will behave. Ability to use the language of mental states is normally acquired early in childhood, without special training. This naïve use of mental state concepts is variously called folk psychology, theory of mind, mentalizing, or mindreading and is studied in both philosophy and the cognitive sciences, including developmental psychology, social psychology, and cognitive neuroscience. One approach to mindreading holds that mental-state attributors use a naïve psychological "theory" to infer mental states in others from their behavior, the environment, or their other mental states, and to predict their behavior from their mental states. This is called the theory theory (TT). A different approach holds...