The Bell Curve by Richard J. Herrnstein

Intelligence and Class Structure in American Life

The book presents a controversial argument that individual differences in intelligence, as measured by IQ, play a central role in shaping socioeconomic outcomes—education, employment, income, and social mobility—claims substantial heritability for cognitive ability, and uses statistical analyses of survey data to link IQ with poverty, welfare dependence, and crime; it also discusses group differences and the policy implications of these findings, provoking intense debate over its methods, interpretations, and ethical consequences.