theory of mind

n. The understanding each person has about his or her own and other people’s experience and mental processes, which is usually intuitive and some of which is explicit and some of which is implicit. Inferences and predictions based on this make mutual understanding possible and enable our complex social interactions. Most people begin to exhibit some understanding of their own and others' mental workings around age 4, but it appears markedly lacking in individuals with autism and in some cases of mental retardation and psychosis. There is no agreement about which, if any, nonhuman animals have a theory of mind.