The Bell Curve: Intelligence and Class Structure in American Life (5 page)

Psychometricians of the 1930s had debated whether intelligence is almost entirely produced by genes or whether the environment also plays a role. By the 1960s and 1970s the point of contention had shifted dramatically. It had somehow become controversial to claim, especially in public, that genes had any effect at all on intelligence. Ironically, the evidence for genetic factors in intelligence had greatly strengthened during the very period when the terms of the debate were moving in the other direction.

In the psychological laboratory, there was a similar shift. Psychological experimenters early in the century were, if anything, more likely to concentrate on the inborn patterns of human and animal behavior than on how the learning process could change behavior.
¹⁸
But from the 1930s to the 1960s, the leading behaviorists, as they were called, and their students and disciples were almost all specialists in learning theory. They filled the technical journals with the results of learning experiments on rats and pigeons, the tacit implication being that genetic endowment mattered so little that we could ignore the differences among species, let alone among human individuals, and still discover enough about the learning process to make it useful and relevant to human concerns.
¹⁹
There are, indeed, aspects of the learning process that cross the lines between species, but there are also enormous differences, and these differences were sometimes ignored or minimized when psychologists explained their findings to the lay public. B. F. Skinner, at Harvard University, more than any other of the leading behaviorists, broke out of the academic world into public attention with books that applied the findings of laboratory research on animals to human society at large.
²⁰

To those who held the behaviorist view, human potential was almost perfectly malleable, shaped by the environment. The causes of human deficiencies in intelligence—or parenting, or social behavior, or work behavior—lay outside the individual. They were caused by flaws in society. Sometimes capitalism was blamed, sometimes an uncaring or incompetent
government. Further, the causes of these deficiencies could be fixed by the right public policies—redistribution of wealth, better education, better housing and medical care. Once these environmental causes were removed, the deficiencies should vanish as well, it was argued.

The contrary notion—that individual differences could not easily be diminished by government intervention—collided head-on with the enthusiasm for egalitarianism, which itself collided head-on with a halfcentury of IQ data indicating that differences in intelligence are intractable and significantly heritable and that the average IQ of various socioeconomic and ethnic groups differs.

In 1969, Arthur Jensen, an educational psychologist and expert on testing from the University of California at Berkeley, put a match to this volatile mix of science and ideology with an article in the
Harvard Educational Review.
²¹
Asked by the
Review’
s editors to consider why compensatory and remedial education programs begun with such high hopes during the War on Poverty had yielded such disappointing results, Jensen concluded that the programs were bound to have little success because they were aimed at populations of youngsters with relatively low IQs, and success in school depended to a considerable degree on IQ. IQ had a large heritable component, Jensen also noted. The article further disclosed that the youngsters in the targeted populations were disproportionately black and that historically blacks as a population had exhibited average IQs substantially below those of whites.

The reaction to Jensen’s article was immediate and violent. From 1969 through the mid-1970s, dozens of books and hundreds of articles appeared denouncing the use of IQ tests and arguing that mental abilities are determined by environment, with the genes playing a minor role and race none at all. Jensen’s name became synonymous with a constellation of hateful ways of thinking. “It perhaps is impossible to exaggerate the importance of the Jensen disgrace,” wrote Jerry Hirsch, a psychologist specializing in the genetics of animal behavior who was among Jensen’s more vehement critics. “It has permeated both science and the universities and hoodwinked large segments of government and society. Like Vietnam and Watergate, it is a contemporary symptom of serious affliction.”
²²
The title of Hirsch’s article was “The Bankruptcy of ‘Science’ Without Scholarship.” During the first few years after the
Harvard Educational Review
article was published, Jensen could appear in no public forum in the United States without triggering something perilously close to a riot.

The uproar was exacerbated by William Shockley, who had won the Nobel Prize in physics for his contributions to the invention of the transistor but had turned his attention to human variation toward the end of his career. As eccentric as he was brilliant, he often recalled the eugenicists of the early decades of the century. He proposed, as a “thought exercise,” a scheme for paying people with low IQs to be sterilized.
²³
He supported (and contributed to) a sperm bank for geniuses. He seemed to relish expressing sensitive scientific findings in a way that would outrage or disturb as many people as possible. Jensen and Shockley, utterly unlike as they were in most respects, soon came to be classed together as a pair of racist intellectual cranks.

Then one of us, Richard Herrnstein, an experimental psychologist at Harvard, strayed into forbidden territory with an article in the September 1971
Atlantic Monthly.
²⁴
Herrnstein barely mentioned race, but he did talk about heritability of IQ. His proposition, put in the form of a syllogism, was that because IQ is substantially heritable, because economic success in life depends in part on the talents measured by IQ tests, and because social standing depends in part on economic success, it follows that social standing is bound to be based to some extent on inherited differences. By 1971, this had become a controversial thing to say. In media accounts of intelligence, the names Jensen, Shockley, and Herrnstein became roughly interchangeable.

That same year, 1971, the U.S. Supreme Court outlawed the use of standardized ability tests by employers unless they had a “manifest relationship” to the specific job in question because, the Supreme Court held, standardized tests acted as “built-in headwinds” for minority groups, even in the absence of discriminatory intent.
²⁵
A year later, the National Education Association called upon the nation’s schools to impose a moratorium on all standardized intelligence testing, hypothesizing that “a third or more of American citizens are intellectually folded, mutilated or spindled before they have a chance to get through elementary school because of linguistically or culturally biased standardized tests.”
²⁶
A movement that had begun in the 1960s gained momentum in the early 1970s, as major school systems throughout the country, including those of Chicago, New York, and Los Angeles, limited or banned the use of group-administered standardized tests in public schools. A number of colleges announced that they would no longer require the Scholastic Aptitude Test as part of the admissions process. The legal movement against
tests reached its apogee in 1978 in the case of
Larry P.
Judge Robert Peckham of the U.S. District Court in San Francisco ruled that it was unconstitutional to use IQ tests for placement of children in classes for the educably mentally retarded if the use of those tests resulted in placement of “grossly disproportionate” numbers of black children.
²⁷

Meanwhile, the intellectual debate had taken a new and personalized turn. Those who claimed that intelligence was substantially inherited were not just wrong, the critics now discovered, they were charlatans as well. Leon Kamin, a psychologist then at Princeton, opened this phase of the debate with a 1974 book,
The Science and Politics of IQ.
“Patriotism, we have been told, is the last refuge of scoundrels,” Kamin wrote in the opening pages. “Psychologists and biologists might consider the possibility that heritability is the first.”
²⁸
Kamin went on to charge that mental testing and belief in the heritability of IQ in particular had been fostered by people with right-wing political views and racist social views. They had engaged in pseudoscience, he wrote, suppressing the data they did not like and exaggerating the data that agreed with their preconceptions. Examined carefully, the case for the heritability of IQ was nil, concluded Kamin.

In 1976, a British journalist, Oliver Gillie, published an article in the
London Sunday Times
that seemed to confirm Kamin’s thesis with a sensational revelation: The recently deceased Cyril Burt, Britain’s most eminent psychometrician, author of the largest and most famous study of the intelligence of identical twins who grew up apart, was charged with fraud.
²⁹
He had made up data, fudged his results, and invented coauthors, the
Sunday Times
declared. The subsequent scandal was as big as the Piltdown Man hoax. Cyril Burt had not been just another researcher but one of the giants of twentieth-century psychology. Nor could his colleagues find a ready defense (the defense came later, as described in the box). They protested that the revelations did not compromise the great bulk of the work that bore on the issue of heritability, but their defenses sounded feeble in the light of the suspicions that had preceded Burt’s exposure.

For the public observing the uproar in the academy from the sidelines, the capstone of the assault on the integrity of the discipline occurred in 1981 when Harvard paleobiologist Stephen Jay Gould, author of several popular books on biology, published
The Mismeasure of Man.
³²
Gould examined the history of intelligence testing, found that it was peopled by charlatans, racists, and self-deluded fools, and concluded that “determinist arguments for ranking people according to a single scale of intelligence, no matter how numerically sophisticated, have recorded little more than social prejudice.”
³³
The Mismeasure of Man
became a best-seller and won the National Book Critics Circle Award.

The Burt Affair

It would be more than a decade before the Burt affair was subjected to detailed reexamination. In 1989 and 1991, two accounts of the Burt allegations, by psychologist Robert Joynson and sociologist Ronald Fletcher, written independently, concluded that the attacks against Burt had been motivated by a mixture of professional and ideological antagonism and that no credible case of data falsification or fictitious research or researchers had ever been presented.
³⁰
Both authors also concluded that some of Burt’s leading critics were aware that their accusations were inaccurate even at the time they made them. An ironic afterword centers on Burt’s claim that the correlation between the IQs of identical twins reared apart is +.77. A correlation this large almost irrefutably supports a large genetic influence on IQ. Since the attacks on Burt began, it had been savagely derided as fraudulent, the product of Burt’s fiddling with the data to make his case. In 1990, the Minnesota twin study, accepted by most scholars as a model of its kind, produced its most detailed estimates of the correlation of IQ between identical twins reared apart. The procedure that most closely paralleled Burt’s yielded a correlation of +.78.
³¹

Gould and his allies had won the visible battle. By the early 1980s, a new received wisdom about intelligence had been formed that went roughly as follows:

As far as public discussion is concerned, this collection of beliefs, with some variations, remains the state of wisdom about cognitive abilities and IQ tests. It bears almost no relation to the current state of knowledge among scholars in the field, however, and therein lies a tale. The dialogue about testing has been conducted at two levels during the last two decades—the visible one played out in the press and the subterranean one played out in the technical journals and books.

The case of Arthur Jensen is illustrative. To the public, he surfaced briefly, published an article that was discredited, and fell back into obscurity. Within the world of psychometrics, however, he continued to be one of the profession’s most prolific scholars, respected for his meticulous research by colleagues of every theoretical stripe. Jensen had not recanted. He continued to build on the same empirical findings that had gotten him into such trouble in the 1960s, but primarily in technical publications, where no one outside the profession had to notice. The same thing was happening throughout psychometrics. In the 1970s, scholars observed that colleagues who tried to say publicly that IQ tests had merit, or that intelligence was substantially inherited, or even that intelligence existed as a definable and measurable human quality, paid too high a price. Their careers, family lives, relationships with colleagues, and even physical safety could be jeopardized by speaking out. Why speak out when there was no compelling reason to do so? Research on cognitive abilities continued to flourish, but only in the sanctuary of the ivory tower.