Inhelder in her introduction. The reason for this unity is that explanatory adequacy can be attained only by exploring the formative and constructive aspects of

This is Volume XXI of thirty-two in a series of Developmental Psychology. Originally published in 1946, it looks the classification and seriation and the growth

This is Volume XX of thirty-two in the Developmental Psychology series. Initially published in 1954, in Piaget’s words the study of sensorimotor or practical

Cognition and emotions in children.