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In Search of Human Nature:
The Decline and Revival of Darwinism in American Social Thought

by carl degler
oxford university press, 400 pages, $24.95

In the beginning, Charles Darwin explained how human beings evolved from animals by natural selection. One might have expected that this revelation would have a profound effect on disciplines like psychology and anthropology, and that the newly established link to animals would become the foundation for the scientific study of human behavior. Carl Degler tells us that, at first, the Darwinian agenda actually did dominate the human sciences. Darwin himself filled three chapters of The Descent of Man with arguments that the mental and moral faculties of human beings were derived from similar features of animals.

This explanatory project carried some extremely racist implications, however. Because he was determined to establish human continuity with animals, Darwin frequently wrote of “savages and lower races” as intermediate between animals and civilized people. Thus Degler observes that it was as much Darwin himself as any of the so-called “social Darwinists” who set the evolutionary approach to human behavior on a politically unacceptable course. “Thanks to Darwin’s acceptance of the idea of hierarchy among human societies,” he tells us, “the spread and endurance of a racist form of social Darwinism owes more to Charles Darwin than to Herbert Spencer.”

Nor is a scientific grounding for racism the only unsavory heritage of nineteenth-century Darwinism. Degler also cites Darwin’s theories about the intellectual inferiority of women, and describes how Darwin’s cousin, Francis Galton, employed Darwinian logic in favor of an ambitious eugenics program to improve the breed. It is not surprising that such doctrines were unpopular with influential social scientists like the Columbia University anthropologist Franz Boas”and his famous pupils Margaret Mead and Ruth Benedict”who were dedicated to egalitarianism and cultural relativism. Degler rightly emphasizes, however, that the conflict of social science with Darwin involved more than just the use of Darwinism to support specific social prejudices.

A foundational aspect of Darwinian biological theory conflicted with optimistic views about how the human condition might be improved. As Darwinism became neo-Darwinism, it became increasingly clear that the theory ruled out the Lamarckian notion of the heritability of acquired characteristics. At first, reform-minded social scientists had thought that “evolution” would allow improvements in races or groups resulting from a better social environment to be made permanent through inheritance. These hopes were dashed, however, when August Weissman cut off the tails of many generations of mice, thus proving to the satisfaction of biologists that changes affecting an animal’s body or behavior during its lifetime are not passed on to its offspring. Sigmund Freud, a law unto himself, continued to embrace the theory that acquired characteristics are heritable, but reformers of lesser stature were constrained by the facts. As Degler puts it, they had to choose “between biology”which no longer could be seen as experientially cumulative”and culture, which was.”

Of course, the reformers chose the alternative that fitted their social vision. Degler makes clear that the choice was primarily based on ideological rather than scientific considerations. “The main impetus [for the shift from biology to culture] came from a wish to establish a social order in which innate and immutable forces of biology played no role in accounting for the behavior of social groups . . . . To the proponents of culture the goal was the elimination of nativity, race, and sex, and any other biologically based characteristic that might serve as an obstacle to an individual’s self-realization.”

Degler serves up some delightful quotes to illustrate how extreme the rejection of biology was”for example, Berkeley anthropologist Alfred Kroeber’s 1915 declaration that “Heredity cannot be allowed to have acted any part in history.” The main rhetorical weapon employed on behalf of culture was to place an insurmountable burden of proof on anyone offering a biological explanation for some human traits or practice. “As Boas characteristically phrased it, if a biological explanation could not be conclusively proved, then culture must be the causal element.” Behaviorism and egalitarianism were in, eugenics and intelligence testing were out. As the epitome of the transformation, Degler cites Gunnar Myrdal’s immensely influential study of race relations in the United States, An American Dilemma. Myrdal wrote at the end of this book that “We have today in social science a greater trust in the improvability of man and society than we have ever had since the Enlightenment.”

This optimism was purchased at the cost of a certain intellectual incoherence, however. Degler considers it profoundly ironic that social scientists became convinced “that human beings in their social behavior, alone among animals, have succeeded in escaping biology . . . . For that belief is accompanied by another deeply held conviction: that human beings, like all other living things, are products of the evolution that Charles Darwin explained with his theory of natural selection. The irony is almost palpable inasmuch as Darwin entertained no doubt that behavior was as integral a part of human evolution as bodily shape.”

Rejection of Darwinism in human behavior furthered the professional independence of social science from biological science at the same time that it encouraged visions of human perfectibility. On the other hand, social scientists have always wanted to be recognized as genuine scientists, an aspiration which requires that they somehow connect their disciplines to the rest of the scientific enterprise. The problem they faced after consolidating the triumph of culture was to find a way to reincorporate a certain amount of biology without allowing it to set the social science agenda or to impose limits on human possibilities. The obvious solution was to readmit biological theories of human behavior up to a point, but to keep them on a short political leash.

The second half of Degler’s book describes a “return of biology” in recent decades that has featured figures such as Edward O. Wilson, Konrad Lorenz, Nicolaus Tinbergen, and William Hamilton. Degler insists that this renewed interest in biology “is not simply a revival of repudiated ideas, like racism, sexism, or eugenics. The evolutionary approach to social science has no more place for them than has the currently dominant cultural interpretation . . . . Rather, the true aim of these social scientists who advocate a ‘return’ is to ask how human beings fit into that which Darwin laid down over a century ago and which very few social scientists consciously repudiate”except when the behavior of human beings is included in it.”

In short, the biologically minded social scientists know better than to repeat the heresies that led to the banishment of their predecessors. If there are any exceptions, they are tactfully ignored. Degler devotes no space to persons who have suggested that there may be inherited group differences in intelligence, for example. (Berkeley’s Arthur Jensen appears only in a footnote, so Degler can explain that his work on race and intelligence testing does not draw upon “either sociobiology or evolutionary theory,” but “is more properly seen as following in the tradition of psychological testing of the 1920s.”) The possible existence of biology”based behavioral differences between men and women is discussed primarily from a feminist perspective, or at least by researchers respectful of feminist sensitivities. No one proposes a revival of the eugenics movement, or even feels the need to explain why a eugenics program is not a good idea from a Darwinian standpoint.

The political leash is so securely fashioned that it hardly ever needs to be jerked. Nonetheless, some voices of the left like Harvard biologists Richard Lewontin and Stephen Jay Gould remain intensely suspicious of sociobiology even when it comes with a liberal spin. Their objection is not to the immediate political agenda of the sociobiologists, but to the inherent potential of biological theories of human behavior to provide comfort for those who think the existing distribution of wealth and power is “natural.” As a result, biological theorizing still occupies only a marginal position in the culture of academic social science.

Degler is always interesting and informative, but it is hard to take seriously a “return to biology” in social science that is so severely constrained by ideology. All that seems to have happened is the spreading of a Darwinian gloss on the ideals of the priesthood of culture. What Degler calls “social science” is less a science than a secularized version of liberation theology. This secular theology can tolerate a biology that is obedient to ideology, but it dare not risk the kind of uncontrolled scientific investigation that might tell us something about human nature and capabilities that we would rather not know.

Darwinism was valuable to anthropologists like Boas, Benedict, Kroeber, and Mead because it did so much to discredit religious authority, and thus seemed to leave humans free to chart their own course in a world without restrictions. The cultural anthropologists, psychologists, and social engineers had to accept Darwinism to explain the history of life up to a point when human culture began, because they regarded theistic religion as so much superstition. But once Darwinism had served to liberate humanity from God, its continuing presence inherently threatened to legitimate restrictions on human possibilities by subjecting human behavior to the all-conquering power of natural selection. The reformers could tolerate Darwinism only if it respected the sacred doctrines of human equality and perfectibility, and paid its way by helping the visionaries to claim the authority of science. If evolutionary biology has indeed returned to social science, it is by way of the servants’ entrance. 

Phillip E. Johnson teaches at Boalt Hall, the law school of the University of California at Berkeley. The author of Darwin on Trial, his article “Creator or Blind Watchmaker?” appeared in the January issue of First Things.

Image by Tim Bryant via Creative Commons. Image cropped.