The Bell Curve

The Bell Curve: Intelligence and Class Structure in American Life is a 1994 book by psychologist Richard J. Herrnstein and political scientist Charles Murray, in which the authors argue that human intelligence is substantially influenced by both inherited and environmental factors and that it is a better predictor of many personal outcomes, including financial income, job performance, birth out of wedlock, and involvement in crime than are an individual's parental socioeconomic status. They also argue that those with high intelligence, the "cognitive elite", are becoming separated from those of average and below-average intelligence, and that this separation is a source of social division within the United States.

The book has been, and remains, highly controversial, especially where the authors discussed purported connections between race and intelligence and suggested policy implications based on these purported connections. The authors claimed that average intelligence quotient (IQ) differences between racial and ethnic groups are at least partly genetic in origin, a view that is now considered discredited by mainstream science. Many of the references and sources used in the book were advocates for racial hygiene, whose research was funded by the white supremacist organization Pioneer Fund.

Shortly after its publication, many people rallied both in criticism and in defense of the book. A number of critical texts were written in response to it. Several criticisms were collected in the book The Bell Curve Debate.