Dr. Jensen, who spent much of his career at the University of California at Berkeley, was one of the most provocative figures in 20th century psychology.
In 1969, Dr. Jensen reignited a long-simmering debate over race and intelligence with an article in the Harvard Educational Review defending studies showing whites scored an average of 15 points higher than blacks on standard IQ tests. He argued that the gap was largely because of genetic differences between the two groups and not, as he had previously believed, attributable to cultural and environmental factors.
His assertions, which came amid the social and political turmoil of the late 1960s, stirred critics to call him a racist. His lectures were disrupted by angry mobs, bomb squads handled his mail, and irate colleagues mounted a campaign to formally censure him.
The effort failed, and the tenured professor continued to teach at Berkeley until his retirement in 1994, but controversy dogged him for years. In 1977, Margaret Mead, the eminent anthropologist, attempted to block his nomination as a fellow of the American Association for the Advancement of Science, arguing that his selection would amount to an endorsement of racist theories.
She lost, but his notoriety endured. In the 1990s protesters in London pelted him with tomatoes at a lecture hall. “Jensenism” became a term of rebuke, used against those who championed theories about whites’ superiority. “Jensenism,” evolutionary biologist Stephen Jay Gould once declared, rested “on a rotten edifice.”
Dr. Jensen “took incredible abuse,” said Charles Murray, the political scientist whose 1994 bestseller, “The Bell Curve,” co-written with Harvard professor Richard J. Herrnstein, opened the next chapter in the so-called IQ wars with a wide-ranging examination of intelligence and class structure that included a discussion of racial differences in intelligence.
“Although he had this reputation as a very controversial figure, he was actually a pure academic and almost a naive one,” Murray said. “He was . . . devoted to analysis and kind of obtuse about the reaction he would provoke with the findings he came out with.”
James R. Flynn, an authority on IQ tests who gained prominence with his discovery of the worldwide increase in IQ scores known as the “Flynn effect,” said in a recent interview that Dr. Jensen made “landmark contributions” to psychology, most of which had nothing to do with questions of race.
Dr. Jensen asserted that IQ tests were valid measures of intelligence that did not discriminate against blacks or other minorities. This was the subject of his 1980 book, “Bias in Mental Testing,” which Flynn called a classic in the field of psychological measurement.