Reviews current research on children's concepts and categories that reflects a growing consensus that nonperceptual knowledge is central to concepts and determines category membership, whereas perceptual knowledge is peripheral in concepts and only a rough guide to category membership. Argues that there is no compelling basis in theory or in data…

A review is presented of research findings on the operation and functions of the two hemispheres of the brain. In tracing discoveries on hemispheric specialization (the left processing information objectively, linguistically, and linearly; the right, spacially, intuitively, and creatively) the importance of achieving a balance between the…