A fundamental ontological distinction that governs much of human behavior is that between the realms of the mental and the physical. An awareness of this distinction informs most, if not all, of adults' predictions for and explanations of events in the world. Thus, an important developmental question arises: When do children become aware of this distinction? Recent research has documented that, in their early years, children in Western cultures are acquiring considerable knowledge about how the mind and reality are both distinct and related. For example, children know that mental entities have very different properties from physical things (Estes, Wellman, & Woolley, 1989; Wellman & Estes, 1986). They also understand that mental states are related to the world in important ways, in particular in the form of beliefs and knowledge (Astington, 1993; Bartsch & Wellman, 1995; Perner, 1991; Astington, 1993). These pieces of knowledge are part of what many have called a “theory of mind” and arguably represent one of children's earliest bodies of knowledge to be used in understanding the world (Wellman, 1990).

Yet a consideration of certain cultural practices in Western society highlights a potential developmental oddity. At about the same age at which children begin to demonstrate that they have the basic components of a theory of mind, they are introduced by our culture to concepts that seem to contradict the knowledge that they are in the process of mastering.