Facts We Can Never Un-Know : THE EVOLUTION OF RACISM; Human Differences and the Use and Abuse of Science <i> By Pat Shipman (Simon & Schuster: $23; 318 pp.)</i>

Suppose, implausibly, that Charles Darwin had never lived and nobody else had made his discoveries. Suppose that throughout the past century and a half we had remained ignorant of evolution, natural selection and the common descent of human beings and apes. Is it conceivable that the forced sterilization of 36,000 Americans in the name of racism and the discrimination toward and oppression of black people in South Africa and elsewhere might not have happened?

“What if?” history is rarely illuminating, but in this case it is pertinent because some of the most murderous racists of our century explicitly appealed to scientific authority for their actions. Hitler’s “Mein Kampf” in places paraphrases and plagiarizes the work of the biologist Ernst Haeckel, the man who championed Darwin in Germany and enjoyed great success as a popularizer of his own somewhat mystical and racist version of evolutionary theory. Nor, to quote Pat Shipman, was Nazi thinking “simply foisted on innocent and reluctant scientists by evil politicians.” Most German scientists were enthusiastic eugenicists long before the Nazis came to power.

The discovery that evolution works by the selective survival of superior strains in competition with each other had direct, vast and terrible political implications. It cannot claim to be free of responsibility for the political abuse of those implications. And yet it is also a truth. Like nuclear fission, natural selection and genetic variation are powerful but morally neutral facts that we can never un-know.

Yet it was precisely to un-know these facts that became the fashion in the late 1940s. Pat Shipman’s book, after exploring the way racism and eugenics drew on far-from-innocent biology in the 1920s and 1930s, then investigates how liberal political assumptions drove biology into a bizarre attempt to deny genetic differences among people after World War II. Beginning with the vicious arguments over UNESCO’s Statement on Race, in which the anthropologist Ashley Montagu argued that race is “not so much a biological phenomenon as a social myth” (why can’t it be both?), this trend continued with the brutal ostracizing of the distinguished, if old-fashioned, anthropologist Carleton Coon in the 1960s for writing a book that investigated the biology, rather than the sociology, of race.

Coon’s book sounds not just insensitive, but wrong as well, to my ears. But Shipman defends his right to be wrong; his motives were plainly above reproach. This leads into some difficult territory. In May 1962, for example, Coon refused to allow the American Assn. of Physical Anthropologists, of which he was president, to vote on a resolution that all races were of equal intelligence--not because he believed it was untrue, but because nobody knew if it was true or not and, in Shipman’s paraphrase of his view, “The truth was the truth and would remain so, silly resolutions notwithstanding.”

Wishful thinking will not make scientific truths more congenial to political virtue. Eugenics works--dog breeding proves it. In the 1920s there was nothing logically wrong with the idea that sterilizing the mentally retarded would (eventually and partially) reduce the rate of mental retardation, although there was a lot that was morally wrong with it. There is nothing logically wrong with the idea that human races differ genetically from one another--they do. It is racism, not race, that is wrong; eugenics, not genetic differences.

Shipman is uncompromising in her criticism of those who would prefer not to know what genetic differences among human groups are: “Rather than face the monster, we have played instead at politicizing first evolutionary theory and then genetics. . . . We have fought each other . . . instead of fighting ignorance. In so doing we have given hate-mongers time to feed the monster. It has swelled on a steady diet of racial divisiveness, lies and half truths until it is strong enough now to destroy us all.”

A physical anthropologist herself, Shipman has written a courageous, thought-provoking and elegant book. To tell the stories of both prewar eugenics and the postwar taboo on letting the insights of genetics and evolution into the study of humanity, she examines the lives of participants in the debate, starting with Charles Darwin himself. Extraordinary figures come alive, such as Rudolf Virchow, the formidable and brilliant mentor and opponent of Haeckel, and Ashley Montagu, the humble London Jew who renamed himself first as a British aristocrat and then as an American academic. It is a successful formula for such a book, and brings the dilemmas of politicized science naturally to the surface.

Shipman ends her book with the story of legal scholar David Wasserman’s innocent attempt in 1992 to hold a conference to discuss the legal implications of impending discoveries about the genetic basis of criminality: an admirable attempt to address a thorny issue before it arose. The conference was ambushed by political activists who saw it as part of a sinister campaign within the Bush Administration to justify the forced sedation or sterilization of black youths. They argued that, however innocent Wasserman’s intentions might be, he could not discuss the genetics of criminality without meaning the racial aspects of criminality, and that scientists must bear responsibility for the abuse of such discussions.

Yet here, for the first time, Shipman’s touch fails her. For, in making the argument that “ignorance is never a solution,” she misses a chance to go even further, and take up the arguments of Wasserman’s critics. Those who belong to races that have been subject to racism have a justifiable complaint to make against evolutionary biology, in my view. Evolutionary biologists have studied race, which is not a human failing, but they have not studied racism, which is.

Human beings are plainly equipped with an instinct to fear, dislike, denigrate and be violent toward people who appear to be from other tribes, bands or out-groups. Latent racism (rendered patent by certain external circumstances) is therefore part of our nature, just as it is part of chimpanzee nature. To argue thus does not for a moment justify prejudice, any more than arguing that homicidal behavior in certain circumstances is part of human nature justifies murder. To design social brakes upon racism, as upon murder, we need to understand better what triggers the expression of the instinct. That requires biology as well as sociology. Let racists, for a change, be the laboratory rats.