Arthur Jensen (born August 24 1923) is a Professor Emeritus of educational psychology at the University of California, Berkeley. Jensen is known for his work in psychometrics and differential psychology, which is concerned with how and why individuals differ behaviorally from one another. He is a major proponent of the hereditarian position in the nature versus nurture debate, the position that concludes genetics play a significant role in behavioral traits, such as intelligence and personality. He is the author of over 400 scientific papers published in refereed journals and currently sits on the editorial boards of the scientific journals Intelligence and ''Personality and Individual Differences.
While he has been rated an eminent psychologist, Jensen remains a controversial figure, largely for his opinions on race-based differences in intelligence.
Jensen was born August 24, 1923, to a father of Danish ancestry and a mother who was half Polish Jewish and half German (non-Jewish).. Jensen studied at University of California, Berkeley (B.A. 1945), San Diego State College (M.A., 1952) and Columbia University (Ph.D., 1956). Jensen did his doctoral thesis on the Thematic Apperception Test. From 1956 through 1958, Jensen did his postdoctoral research at the University of London, Institute of Psychiatry. Upon returning to the United States, Jensen became a researcher and professor at the University of California, Berkeley, where he focused on individual differences in learning, especially the influences of culture, development, and genetics on intelligence and learning. Jensen received tenure at Berkeley in 1962 and was given his first sabbatical in 1964. He has concentrated much of his work on the learning difficulties of culturally disadvantaged students. In 2003, Jensen was awarded the Kistler Prize for original contributions to the understanding of the connection between the human genome and human society.
Jensen has had a lifelong interest in classical music and was, early in his life, attracted by the idea of becoming a conductor himself. At fourteen, Jensen conducted a band that won a nationwide contest held in San Francisco. Later, Jensen conducted orchestras and attended a seminar given by Nikolai Sokoloff. Soon after graduating from Berkeley, Jensen moved to New York, mainly to be near the conductor Arturo Toscanini. Jensen was also deeply interested in the life and example of Gandhi, producing an unpublished book-length manuscript on his life. During Jensen's period in San Diego he spent time working as a social worker with the San Diego Department of Public Welfare.
Jensen's interest in learning differences directed him to the extensive testing of black, Mexican-American, and other minority-group school children. The results led him to distinguish between two separate types of learning ability. Level I, or associative learning, may be defined as retention of input and rote memorization of simple facts and skills. Level II, or conceptual learning, is roughly equivalent to the ability to manipulate and transform inputs, that is, the ability to solve problems. Statistical analysis of his findings led Jensen to conclude that Level I abilities were distributed equally among members of all races, but that Level II occurred with significantly greater frequency among whites and Asian-Americans than among African-Americans and Mexican-Americans.
Later, Jensen was an important advocate in the mainstream acceptance of general intelligence factor, a concept which was essentially synonymous with his Level II conceptual learning. General intelligence factor, or g, is an abstraction that stems from the observation that scores on all forms of cognitive tests correlate positively with one another. Jensen claimed, on the basis of his research, that general cognitive ability is essentially an inherited trait, determined predominantly by genetic factors rather than by environmental conditions. He also contended that while associative learning, or memorizing ability, is equally distributed among the races, conceptual learning, or synthesizing ability, occurs with significantly greater frequency in whites than in blacks. He suggested that from the data, one might conclude that on average, white Americans are more intelligent than African-Americans.
Jensen's most controversial work, published in February 1969 in the Harvard Educational Review, was titled "How Much Can We Boost I.Q. and Scholastic Achievement?" It concluded, among other things, that Head Start programs designed to boost African-American IQ scores had failed, and that this was likely never to be remedied, largely because, in Jensen's estimation, heritability of IQ was over 0.7 of the within-race IQ variability, and the 0.3 left over was due to non-shared environmental influences.
The work became one of - if not the most - cited papers in the history of psychological testing and intelligence research. The release of Jensen's paper, How Much Can We Boost I.Q. and Scholastic Achievement?, sparked a huge academic controversy. Although his paper was widely cited, a random selection of 60 of these citations revealed that 29 of the papers were direct rebuttals or criticisms of Jensen's arguments, 8 cited the paper as an "example of controversy," 8 used it as a background reference. Only 15 citations of Jensen's paper were in any way supportive of his theories, and 7 of these 15 were only in relation to minor points.
After the paper was released, students and faculty staged large protests outside Jensen's U.C. Berkeley office. There may have been death threats against him. Jensen was denied reprints of his work by his publisher and was not permitted to reply in response to letters of criticism -- both extremely unusual policies for their day. Many colleagues at the time felt that even if Jensen's work contained no scientific merit, his treatment was itself against the spirit of science and the free exchange of ideas. In a later article, Jensen argued that his claims had been misunderstood:
Thomas Sowell wrote:
However, Jensen's 1998 The g Factor: The Science of Mental Ability gives his position suggesting a genetic component is implicated in the white-black difference in IQ:
In 1994 he was one of 52 signatories on "Mainstream Science on Intelligence," an editorial written by Linda Gottfredson and published in the Wall Street Journal, which defended the findings on race and intelligence in The Bell Curve.
In 1995 an American Psychological Association task force published a paper titled "Intelligence: Knowns and Unknowns" which concluded that within the white population the heritability of IQ is "around .75" but also "It is sometimes suggested that the Black/White differential in psychometric intelligence is partly due to genetic differences (Jensen, 1972) There is not much direct evidence on this point, but what little there is fails to support the genetic hypothesis."
Melvin Konner wrote in the notes to his book The Tangled Wing: Biological Constraints on the Human Spirit:
Many studies that purport to be both science-based and attempt to influence public policy have been accused of scientific racism. Konner wrote:
Lisa Suzuki and Joshua Aronson of New York University wrote in 2005 that Jensen has largely ignored evidence that fails to support his position that IQ test score gaps represent a genetic racial hierarchy unwaveringly for over 30 years. During this time Jensen has received more than a million dollars from the often-criticized Pioneer fund.
Paleontologist and evolutionary biologist Stephen Jay Gould, attacked Jensen's work in his 1981 book The Mismeasure of Man. Gould writes that Jensen misapplies the concept of "heritability", which is defined as a measure of the variation of a trait due to inheritance within a population (Gould 1981: 127; 156-157). Jensen uses heritability to measure differences between populations. Gould also disagrees with Jensen's belief that IQ tests measure a real variable, g, or "the general factor common to a large number of cognitive abilities" which can be measured along a unilinear scale. This is a claim most closely identified with Charles Spearman. According to Gould, Jensen misunderstood the research of L. L. Thurstone to ultimately support this claim; Gould, however, argues that Thurstone's factor analysis of intelligence revealed g to be an illusion (1981: 159; 13-314). Gould criticizes Jensen's sources including his use of Catharine Cox's 1926 Genetic Studies of Genius, which examines historiometrically the IQs of historic intellectuals after their deaths (Gould 1981: 153-154).
In a 1982 review of The Mismeasure of Man, Jensen gives point-by-point rebuttals to much of Gould's critique, including Gould's treatment of heritability, the "reification" of g, and the use of Thurstone's analysis. Gould responded to Jensen's rebuttals in a revised edition of the book, published in 1996.
While Jensen recognizes the validity of some of Gould's claims, in many places, he criticizes Gould's general approach
Jensen adds that Gould made a number of misrepresentations, whether intentional or unintentional, while purporting to present Jensen's own positions