Abstract
The principal objective of the study was to examine some of the scientific premises of The Bell Curve by Herrnstein and Murray (1996). It was shown that the hypothetical construct referred to as ‘g’ is nothing more than the aggregate of the various cognitive tests contained in the battery of tests that is subjected to factor analysis. The nature of g, therefore, depends on the composition of the test battery. Furthermore, it was shown that the predictive validity of multiple factors is always better than that of g alone. The validity of Spearman’s hypothesis was investigated and found wanting. The critical role of formal schooling in the development of intellect (both fluid and crystallised) was discussed with reference to illiterate adults in South Africa. The importance of the interaction of heredity and environment was stressed. The best genetic endowment can only come to fruition in a stimulating environment. The relationship between locus of control and intelligence was discussed.