Correction appended.

One Saturday in November of 1984, James Flynn, a social scientist at the University of Otago, in New Zealand, received a large package in the mail. It was from a colleague in Utrecht, and it contained the results of I.Q. tests given to two generations of Dutch eighteen-year-olds. When Flynn looked through the data, he found something puzzling. The Dutch eighteen-year-olds from the nineteen-eighties scored better than those who took the same tests in the nineteen-fifties—and not just slightly better, much better.


Flynn has been writing about the implications of his findings—now known as the Flynn effect—for almost twenty-five years. His books consist of a series of plainly stated statistical observations, in support of deceptively modest conclusions, and the evidence in support of his original observation is now so overwhelming that the Flynn effect has moved from theory to fact. What remains uncertain is how to make sense of the Flynn effect. If an American born in the nineteen-thirties has an I.Q. of 100, the Flynn effect says that his children will have I.Q.s of 108, and his grandchildren I.Q.s of close to 120—more than a standard deviation higher. If we work in the opposite direction, the typical teen-ager of today, with an I.Q. of 100, would have had grandparents with average I.Q.s of 82—seemingly below the threshold necessary to graduate from high school. And, if we go back even farther, the Flynn effect puts the average I.Q.s of the schoolchildren of 1900 at around 70, which is to suggest, bizarrely, that a century ago the United States was populated largely by people who today would be considered mentally retarded.

For almost as long as there have been I.Q. tests, there have been I.Q. fundamentalists. H. H. Goddard, in the early years of the past century, established the idea that intelligence could be measured along a single, linear scale. One of his particular contributions was to coin the word “moron.” “The people who are doing the drudgery are, as a rule, in their proper places,” he wrote. Goddard was followed by Lewis Terman, in the nineteen-twenties, who rounded up the California children with the highest I.Q.s, and confidently predicted that they would sit at the top of every profession. In 1969, the psychometrician Arthur Jensen argued that programs like Head Start, which tried to boost the academic performance of minority children, were doomed to failure, because I.Q. was so heavily genetic; and in 1994 Richard Herrnstein and Charles Murray, in “The Bell Curve,” notoriously proposed that Americans with the lowest I.Q.s be sequestered in a “high-tech” version of an Indian reservation, “while the rest of America tries to go about its business.” To the I.Q. fundamentalist, two things are beyond dispute: first, that I.Q. tests measure some hard and identifiable trait that predicts the quality of our thinking; and, second, that this trait is stable—that is, it is determined by our genes and largely impervious to environmental influences.

This is what James Watson, the co-discoverer of DNA, meant when he told an English newspaper recently that he was “inherently gloomy” about the prospects for Africa. From the perspective of an I.Q. fundamentalist, the fact that Africans score lower than Europeans on I.Q. tests suggests an ineradicable cognitive disability. In the controversy that followed, Watson was defended by the journalist William Saletan, in a three-part series for the online magazine Slate. Drawing heavily on the work of J. Philippe Rushton—a psychologist who specializes in comparing the circumference of what he calls the Negroid brain with the length of the Negroid penis—Saletan took the fundamentalist position to its logical conclusion. To erase the difference between blacks and whites, Saletan wrote, would probably require vigorous interbreeding between the races, or some kind of corrective genetic engineering aimed at upgrading African stock. “Economic and cultural theories have failed to explain most of the pattern,” Saletan declared, claiming to have been “soaking [his] head in each side’s computations and arguments.” One argument that Saletan never soaked his head in, however, was Flynn’s, because what Flynn discovered in his mailbox upsets the certainties upon which I.Q. fundamentalism rests. If whatever the thing is that I.Q. tests measure can jump so much in a generation, it can’t be all that immutable and it doesn’t look all that innate.









This is not a trivial issue. I.Q. tests are used to diagnose people as mentally retarded, with a score of 70 generally taken to be the cutoff. You can imagine how the Flynn effect plays havoc with that system. In the nineteen-seventies and eighties, most states used the WISC-R to make their mental-retardation diagnoses. But since kids—even kids with disabilities—score a little higher every year, the number of children whose scores fell below 70 declined steadily through the end of the eighties. Then, in 1991, the WISC III was introduced, and suddenly the percentage of kids labelled retarded went up. The psychologists Tomoe Kanaya, Matthew Scullin, and Stephen Ceci estimated that, if every state had switched to the WISC III right away, the number of Americans labelled mentally retarded should have doubled.

That is an extraordinary number. The diagnosis of mental disability is one of the most stigmatizing of all educational and occupational classifications—and yet, apparently, the chances of being burdened with that label are in no small degree a function of the point, in the life cycle of the WISC, at which a child happens to sit for his evaluation. “As far as I can determine, no clinical or school psychologists using the WISC over the relevant 25 years noticed that its criterion of mental retardation became more lenient over time,” Flynn wrote, in a 2000 paper. “Yet no one drew the obvious moral about psychologists in the field: They simply were not making any systematic assessment of the I.Q. criterion for mental retardation.”

Flynn brings a similar precision to the question of whether Asians have a genetic advantage in I.Q., a possibility that has led to great excitement among I.Q. fundamentalists in recent years. Data showing that the Japanese had higher I.Q.s than people of European descent, for example, prompted the British psychometrician and eugenicist Richard Lynn to concoct an elaborate evolutionary explanation involving the Himalayas, really cold weather, premodern hunting practices, brain size, and specialized vowel sounds. The fact that the I.Q.s of Chinese-Americans also seemed to be elevated has led I.Q. fundamentalists to posit the existence of an international I.Q. pyramid, with Asians at the top, European whites next, and Hispanics and blacks at the bottom.

Here was a question tailor-made for James Flynn’s accounting skills. He looked first at Lynn’s data, and realized that the comparison was skewed. Lynn was comparing American I.Q. estimates based on a representative sample of schoolchildren with Japanese estimates based on an upper-income, heavily urban sample. Recalculated, the Japanese average came in not at 106.6 but at 99.2. Then Flynn turned his attention to the Chinese-American estimates. They turned out to be based on a 1975 study in San Francisco’s Chinatown using something called the Lorge-Thorndike Intelligence Test. But the Lorge-Thorndike test was normed in the nineteen-fifties. For children in the nineteen-seventies, it would have been a piece of cake. When the Chinese-American scores were reassessed using up-to-date intelligence metrics, Flynn found, they came in at 97 verbal and 100 nonverbal. Chinese-Americans had slightly lower I.Q.s than white Americans.

The Asian-American success story had suddenly been turned on its head. The numbers now suggested, Flynn said, that they had succeeded not because of their higher I.Q.s. but despite their lower I.Q.s. Asians were overachievers. In a nifty piece of statistical analysis, Flynn then worked out just how great that overachievement was. Among whites, virtually everyone who joins the ranks of the managerial, professional, and technical occupations has an I.Q. of 97 or above. Among Chinese-Americans, that threshold is 90. A Chinese-American with an I.Q. of 90, it would appear, does as much with it as a white American with an I.Q. of 97.

There should be no great mystery about Asian achievement. It has to do with hard work and dedication to higher education, and belonging to a culture that stresses professional success. But Flynn makes one more observation. The children of that first successful wave of Asian-Americans really did have I.Q.s that were higher than everyone else’s—coming in somewhere around 103. Having worked their way into the upper reaches of the occupational scale, and taken note of how much the professions value abstract thinking, Asian-American parents have evidently made sure that their own children wore scientific spectacles. “Chinese Americans are an ethnic group for whom high achievement preceded high I.Q. rather than the reverse,” Flynn concludes, reminding us that in our discussions of the relationship between I.Q. and success we often confuse causes and effects. “It is not easy to view the history of their achievements without emotion,” he writes. That is exactly right. To ascribe Asian success to some abstract number is to trivialize it.





Flynn then talked about what we’ve learned from studies of adoption and mixed-race children—and that evidence didn’t fit a genetic model, either. If I.Q. is innate, it shouldn’t make a difference whether it’s a mixed-race child’s mother or father who is black. But it does: children with a white mother and a black father have an eight-point I.Q. advantage over those with a black mother and a white father. And it shouldn’t make much of a difference where a mixed-race child is born. But, again, it does: the children fathered by black American G.I.s in postwar Germany and brought up by their German mothers have the same I.Q.s as the children of white American G.I.s and German mothers. The difference, in that case, was not the fact of the children’s blackness, as a fundamentalist would say. It was the fact of their Germanness—of their being brought up in a different culture, under different circumstances. “The mind is much more like a muscle than we’ve ever realized,” Flynn said. “It needs to get cognitive exercise. It’s not some piece of clay on which you put an indelible mark.” The lesson to be drawn from black and white differences was the same as the lesson from the Netherlands years ago: I.Q. measures not just the quality of a person’s mind but the quality of the world that person lives in.

CORRECTION: In his December 17th piece, “None of the Above,” Malcolm Gladwell states that Richard Herrnstein and Charles Murray, in their 1994 book “The Bell Curve,” proposed that Americans with low I.Q.s be “sequestered in a ‘high-tech’ version of an Indian reservation.” In fact, Herrnstein and Murray deplored the prospect of such “custodialism” and recommended that steps be taken to avert it. We regret the error.