The construct of general intelligence

Abstract

The construct of general intelligence is discussed in a number of different contexts. The fundamental empirical basis for it is the positive trend among the smallest correlations among cognitive measures. Differences among factor models which recognize this in different ways are discussed. Evidence for the general factor in intelligence is also found in the difficulty in finding evidence for differential validity of tests from one criterion to another. Performance on Piagetian tasks reflects mainly general intelligence. Individual differences in aural comprehension of language anticipate later individual differences in intellectual development. Selective forces which produce differences among schools operate largely on the general factor. To the extent that there is a genetic contribution to individual differences on cognitive tests, it appears to be to the general factor variance. Social class differences among whites appear to be largely on the general factor, but black-white differences require other dimensions. Although the general factor is, in a sense, real, it is not interpreted as an entity within the organism. Instead it is an abstraction resulting from the many genes, the many environmental pressures, and the many neural structures involved in the wide variety of human behaviors which can be labelled cognitive or intellectual.