In contrast to earlier notions, a systems view of an organism's development sees genes as only one component in a hierarchy of influences that produces finished traits and differentiation. Developmental canalization proceeds from genes, behavior, and environment as well as from the coaction of these factors. (BC)

In all of his published work, Jean Piaget never abandoned his original theoretical framework for the understanding of human development. This framework insists that intelligence is essentially a biological phenomenon; its development is best understood as the development of a sophisticated and highly successful adaptation device. This device…