Introduction Individual Differences in Theory of Mind: What Are We Investigating?
Since the early 1980s, the acquisition of a theory of mind, defined as the ability to predict and explain people’s behavior with reference to mental states, has been seen as a crucial watershed in social-cognitive development: one that changes the toddler from a literal observer of human behavior to a folk psychologist, capable of making complex mental-state attributions, engaging in elaborate social and communicative games, and even deception. Theory of mind ability, variously referred to as mentalizing, mind reading, or belief-desire psychology, has traditionally been viewed as the foundation for our adultlike understanding of the social world. As Wellman (1990) expressed it:
Why is achievement of a theory of mind important?…belief-desire psychology is our framework theory of persons. As a framework theory it dictates our basic ontology, our parsing of personal action and thought into its most basic categories. And it dictates our causal-explanatory infrastructure, our basic grasp of how to go about making sense of ourselves and others. In short, belief-desire psychology frames our worldview. (p. 328)
Thus, individual differences in theory of mind ability presumably have important implications for children’s and adults’ everyday social interactions. This view is most strongly stated in the theory of mind deficit account of autism (e.g., Baron-Cohen, Leslie, & Frith, 1985; Baron-Cohen, Tager-Flusberg, & Cohen, 1993), where it is argued that the atypical social and communicative behavior of individuals with autism results from their failure to acquire a theory of mind.