History of the race and intelligence controversy

The history of the race and intelligence controversy concerns the historical development of a debate, concerning possible explanations of group differences encountered in the study of race and intelligence. Since the beginning of IQ testing around the time of World War I there have been observed differences between average scores of different population groups, but there has been no agreement about whether this is mainly due to environmental and cultural factors, or mainly due to some genetic factor, or even if the dichotomy between environmental and genetic factors is a correct approach to the debate.In the late nineteenth and early twentieth century, group differences in intelligence were assumed to be due to race and, apart from intelligence tests, research relied on measurements such as brain size or reaction times. By the mid-1930s most psychologists had adopted the view that environmental and cultural factors predominated. In the mid-1960s, physicist William Shockley sparked controversy by claiming there might be genetic reasons that black persons in America tended to score lower on IQ tests than whites. In 1969 the educational psychologist Arthur Jensen published a long article with the suggestion that compensatory education had failed to that date because of genetic group differences. A similar debate among academics followed the publication in 1994 of The Bell Curve by Richard Herrnstein and Charles Murray. Their book prompted a renewal of debate on the issue and the publication of several interdisciplinary books on the issue. One contemporary response was a report from the American Psychological Association that found no conclusive explanation for the observed differences between average IQ scores of racial groups. A 2012 review article in the journal American Psychologist and a rejoinder to a reply to that article are some of the latest publications prompted by the debate.