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Is Aggression Imprinted In Human Nature?

Is there a killer instinct, and if so, can it be controlled?

This post is a review of Killer Instinct: The Popular Science Of Human Nature In Twentieth Century America. By Nadine Weidman. Harvard University Press. 360 pp. $45.

With the publication of two bestsellers in 1966 — On Aggression, by Konrad Lorenz, an Austrian ornithologist and co-founder of ethology, the study of animal behavior in the wild, and Territorial Integrity, by Robert Ardrey, a playwright and Hollywood screenwriter — the idea of the “killer instinct” entered the mainstream of popular science. Albeit in different ways, Lorenz and Ardrey endorsed the Darwinian notion that aggression was innate but argued that it could be controlled if human beings learned from animals (like Cichlid “fighting fish”) how to channel it to strengthen social bonds.

istock by Getty images
Source: istock by Getty images

Ashley Montagu, an anthropologist and public intellectual, emerged as the chief critic of the theorists he derisively dubbed “aggressionists.” An environmentally enhanced tendency toward cooperation, altruism and love, Montagu insisted, was more dominant in human beings than egoism, antagonism, and aggression. In the 1970s, Harvard Professor Edward O. Wilson, the world’s leading expert on ants, maintained that his theory of sociobiology was an objective approach to studying animal and human behavior, which struck an appropriate balance between ethologists and environmental determinists.

In Killer Instinct, Nadine Weidman, a lecturer in the History of Science at Harvard University, author of Constructing Scientific Psychology and co-author of Race, Racism, and Science, examines the debates about an instinct for violence as they were conducted through popular science media. Informative, accessible, and filled with fascinating portraits of her large cast of characters, Weidman’s book makes an important contribution to our understanding of how ideas about nature and nurture were constructed, contested, and disseminated in the United States between the 1950s and 1980s.

To burnish his reputation as an authority on the human instincts for mother love and aggression, Weidman reveals, Lorenz, who was awarded the Nobel Prize in 1973 for his work on insects, fish, and birds, forged alliances with psychoanalyst Anthony Storr and John Bowlby, the pioneer of attachment theory. Drawing on psychology, Lorenz pointed out that aggression could be healthy while suggesting that sports contests and campaigns to address hunger, disease and ignorance could relieve aggressive drives. But he also captured public attention during the Cold War by asking repeatedly whether individuals in a nuclear confrontation would act instinctively (like wolves) or activate their inhibitions (like doves). And, according to Weidman, with help from defenders like Margaret Mead, Lorenz managed to explain away his Nazi past as a youthful “aberration,” join Ardrey in placing instincts on the side of individual freedom, and watch their claims about killing as a permanent characteristic enter popular culture on Star Trek and 2001: A Space Odyssey.

Over the course of his career, Weidman points out, Ashley Montagu moderated his belief in human flexibility and educability and moved toward biological essentialism, with cooperation and sociability emerging as stronger forces in evolution. But, “for whatever reason,” this shift did not appear in his “anti-aggressionist” writings. And so, rather than a debate between “rival essentialists,” Montagu remained “an extreme environmentalist” and Lorenz and Ardrey “genetic determinists,” with no room for models in which biological potentials were activated — or not — by environmental conditions. And a “stark nature/nurture dichotomy took center stage.”

Wilson’s position shifted as well, Weidman indicates. In his early work, Wilson questioned Lorenz’s claims that competitive and aggressive instincts in animals were universal and susceptible to neutralization by ritualized rules of conduct. He emphasized variability, across species and within them, and adaptability to changing circumstances. And he denied that evolution was a guide to moral conduct.

That said, Wilson envisioned the new field of sociobiology as a search for common properties linking otherwise vastly different species. He focused on behaviors that facilitated the transmission of an organism’s genes into the next generation. According to Weidman, Wilson came into close alignment with the pop ethologists in On Human Nature (1978). There was an “underlying biological basis,” he asserted, for four “elemental categories” of human behavior: aggression, sex, altruism, and religion. “The genes hold culture on a leash,” Wilson declared. “The leash is very long, but inevitably values will be constrained in accordance with their effect on the human gene pool.” Like Lorenz and Ardrey, he now deemed nature as a moral guide that should be obeyed.

Feminists, Weidman notes, did not fail to notice the sexism inherent in the pop ethologists’ claims that innate aggression was a driver of human evolution. She summarizes the critiques of members of the Sociobiology Study Group and the Genes and Gender Collective, but suggests they might have gotten more traction had they pointed out that sociobiologists insisted that males and females had different essential natures, while refusing to make the same claim for race or any other category.

More generally, Weidman regrets that the controversy over sociobiology became an updated version of the old, unproductive nature versus nurture debate. And that neither side recognized that “the popular science of human nature must always remain inconclusive.”