Core knowledge.

Compex cognitive skills such as reading and calculation and complex cognitive achievements such as formal science and mathematics may depend on a set of building block systems that emerge early in human ontogeny and phylogeny. These core knowledge systems show characteristic limits of domain and task specificity: Each serves to represent a particular class of entities for a particular set of purposes. By combining representations from these systems, however, human cognition may achieve extraordinary flexibility. Studies of cognition in human infants and in nonhuman primates therefore may contribute to understanding unique features of human knowledge.