Jean Piaget : Children and the Inclusion Problem

Jean Piaget, renowned Swiss developmental psychologist and epistemologist, is best known for his groundbreaking studies with children, which led him to develop a landmark theory of cognitive development. Geldolph A. Kohnstamm's Jean Piaget: Children and the Inclusion Problem is a critical study of a cornerstone of Piaget's theory. This theory holds that being able to solve problems of class inclusion marks the beginning of the period of concrete (logical) operations at about seven or eight years of age.