ABSTRACT
This chapter examines the scientific theory of human intelligence. It discusses current knowledge as a basis for indicating where further empirical research is needed. It has become clear that the phenomena referred to as human intelligence is a mosaic of many cognitive capabilities. This mosaic can be partitioned into a finite set of dimensions that fairly completely account for individual differences among a large number of such capabilities. The abilities that psychologists have become able to measure probably do not represent the entire range of capabilities that constitute human intelligence, but they are a good sample. Thousands of different tests have been designed to measure hundreds of features of intelligence. Different tests indicate that what these thousands of tests measure in common are actually fewer than 100 dimensions called primary mental abilities. Further analyses and descriptions of links to developmental and physiological variables indicate that fewer than a dozen broad dimensions describe all major kinds of cognitive capability.
