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intelligence for identical twins reared apart remained exactly the same, even to the third decimal point, 0.771. For that matter, so did the heritability for the control group of twins reared together, 0.944. "The data were simply too perfect to be true," said Kamin. The unlikeliness of such astonishing consistencies was immediately apparent to anyone who had worked with statistics. Kamin also pointed out that Burt offered little information about how he collected the data or even such particulars as the age and sex of the children. "It was a fraud linked to policy from the word go,'' Kamin charged. "The data were cooked in order for him to arrive at the conclusions he wanted." It served to prove, Kamin asserted, that the IQ test itself was nothing more than "an instrument of oppression against the poor."
Kamin's investigation demolished Burt's scholarly reputation. Soon after that, a science reporter for the Sunday Times , Oliver Gillie, published a devastating exposé suggesting that two of Burt's associates, Misses Margaret Howard and J. Conway, who had coauthored papers with Burt and had done much of the actual testing of the twins, "never existed, but were the fantasy of

 

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an aging professor who became increasingly lonely and deaf." Burt was no longer alive to respond to these charges, and neither Howard nor Conway stepped forward to provide evidence of her reality. Jensen, who was a friend of Burt's, sought to defend the great man's honor, but when he tabulated the data from Burt's various studies, he came to the same conclusion as Kamin. In a 1974 article in Behavior Genetics , Jensen decreed that Burt's correlations were "useless for hypothesis testing"in effect, reading Burt out of the scientific literature. "It is almost as if Burt regarded the actual data as merely an incidental backdrop for the illustration of the theoretical issues in quantitative genetics, which, to him, seemed always to hold center stage," Jensen wrote. It was a gentler way of saying what Kamin had been charging, that the data were cooked to support Burt's political bias and class prejudice. The loss of Burt's data appeared to have a profound effect on the measure of the heritability of IQ. Christopher Jencks of Harvard recalculated the figures and found that without Burt's data, the correlation of heredity to IQ dropped from about eighty percent to sixty percent.
An authorized biography in 1979 by Leslie Hearnshaw, who had held the Chair of Psychology at Liverpool University until his retirement, largely agreed with Burt's detractors; for one thing, Hearnshaw wrote that only one twin has ever come forward to claim that he had been tested by Burt. That briefly seemed to settle the matter. However, Burt's reputation was at least partially resuscitated by two subsequent biographies, one in 1989 by the psychologist Robert B. Johnson of the University of Nottingham and the other in 1991 by the sociologist Ronald Fletcher of Reading University. The authors concluded that while Burt may have been a careless researcher, he was probably not the complete

 

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fraud that his detractors described. Moreover, they pointed out that the attack on Burt's reputation by critics holding opposing political views was itself full of careless, prejudicial reporting. Burt's raw data, which would settle much of the argument, had been partially destroyed by a bomb during the London blitz, and what remained of it was burned by his housekeeper after Burt's death, on the advice of one of Burt's bitterest opponents. On the other hand, Professor N. J. Mackintosh, who teaches experimental psychology at the University of Cambridge, re-examined Burt's twin data in 1995 and found substantial reasons to believe the charges of fraud. It is unlikely that this controversy will ever be satisfactorily resolved.
The bitterness of the battle over twin studies has rarely been matched in the history of academic warfare. The question of what twins tell us about human