Human abilities.

This chapter reviews recent literature, primarily from the 1990s, on human abilities. The review opens with a consideration of the question of what intelligence is, and then considers some of the major definitions of intelligence, as well as implicit theories of intelligence around the world. Next, the chapter considers cognitive approaches to intelligence, and then biological approaches. It proceeds to psychometric or traditional approaches to intelligence, and then to broad, recent approaches. The different approaches raise somewhat different questions, and hence produce somewhat different answers. They have in common, however, the attempt to understand what kinds of mechanisms lead some people to adapt to, select, and shape environments in ways that match particularly well the demands of those environments.