in the 1980s, four researchers: "Gottfredson, Gordon, Cattell, and [Richard J.] Herrnstein [of The Bell Curve fame] were part of a small community of intelligence researchers who clung to the overwhelming importance of a single version of general intelligence, or [Charles] Spearman's 'g,' as the predictor of life outcomes at a time when mainstream psychology had moved away from this position. In their work, intelligence became a master key to understanding the success and failure of populations."