Bonobo Business

Primates and Philosophers

How Morality Evolved

Frans de Waal

Princeton University Press, $22.95, 230 pp.

Our Inner Ape

A Leading Primatologist Explains Why We Are Who We Are

Frans de Waal

Riverhead Books, $24.95, 288 pp.

A standard distinction in discussions of science and religion is that science discusses matters of fact and religion discusses matters of value and purpose. Science, so it goes, tells us what is, and religion tells us what ought to be. This division of territory, many argue, keeps religion forever relevant because even the greatest discoveries of science would still leave matters of value and purpose unaddressed.

But what if science had important things to say about our values and purposes? What if not only our bodies but also the origins of our morality are the products of millions of years of evolutionary development? If so, would the explanatory power of science finally succeed in making religion irrelevant?

Frans de Waal, an acclaimed primatologist, has much to say about what he considers the biological origins of morality. Unlike many recent antireligion writers such as Richard Dawkins, Sam Harris, and Daniel Dennett, who use the latest socio-biological research to campaign against religion, de Waal has no antireligious agenda. This both keeps his writing more focused and helps him avoid many of the argumentative errors of Dawkins and company, who regularly seem to assume that scientific expertise translates into philosophical and theological competence. De Waal is a keen social observer, but he focuses mostly on what we can learn from what he knows best-the study of primates, including the human variety.

His most recent book is Primates and Philosophers: How Morality Evolved. The book is based on the Tanner Lectures that de Waal delivered at Princeton’s Center for Human Values, and it includes responses by three philosophers, Peter Singer, Christine M. Korsgaard, and Philip Kitcher, and one by science writer Robert Wright. While this book is accessible to a general audience willing to put in extra effort, the philosophical arguments in the second half of the book might intimidate the nonspecialist. For such a reader, the far better introduction to de Waal’s theory of what the study of primates can teach humans is Our Inner Ape: A Leading Primatologist Explains Why We Are Who We Are. This book draws more on the observation of primates and humans, and less on abstract philosophical distinctions.

In Primates and Philosophers, de Waal proposes a “Russian Doll Model” for the evolution of morality. Here, morality is defined as the promotion of harmony within communities and the placing of boundaries on behavior when interests collide. Morality is concerned with the two H’s, helping and (not) hurting. This may not seem like the most sophisticated definition of morality, but de Waal is looking for the “origins” of morality in primates, not for the complex products of philosophy and theology.

The primitive origin of morality (the innermost Russian doll) is “emotional contagion.” This phenomenon is found in all primates and in many other animals as well. It occurs when the emotional state of one animal induces the same emotional response in another. The distress of one animal can by itself induce distress in other animals. This ability to activate distress in a group, argues de Waal, has clear adaptive advantages, and so is preserved though natural selection.

Humans experience emotional contagion, but we are not inclined to see it strictly as a biological reaction. Instead, we use words like empathy and sympathy. De Waal does not wish to reduce our emotional states to the basic reactions of animals. However, he insists that the human capacity for empathy and sympathy, along with the ability to show concern for others and to universalize such concern within moral systems, depends on the biological capacity for emotional contagion.

Humans are not the only primates capable of empathy and sympathy. In both Primates and Philosophers and in Our Inner Ape, de Waal provides numerous examples of what he considers to be such phenomena in primates. Empathy emerges when a primate is able to differentiate its own emotional response from that of others. Sympathy, a further layer of the Russian doll of morality, involves the ability of one primate to show distress or concern for, and not just with, another. Add to sympathy the cognitive abilities of apes and one observes “targeted-helping,” or the altruistic concern of one ape for the specific needs of another. This helping includes responding to physical needs, like those of a young ape in danger, as well as emotional needs, such as the consolation by a third party of one ape who has lost a confrontation with a rival.

In apes, the ability for targeted-helping extends beyond the species. De Waal recounts the actions of Kuni, a chimpanzee in a British zoo, who saw a bird hit the glass wall inside Kuni’s enclosure. Kuni first put the stunned bird on its feet, then tossed it a short distance. When neither act succeeded in reviving the bird, Kuni took it to the top of a tree, unfolded its wings, and launched it like a toy plane. When this failed, Kuni stood guard over the bird for hours until it revived and flew away. For de Waal, the targeted-helping by human beings for each other, and even other species, is not analogous to helping like that displayed by Kuni, but rather homologous: it is derived from the same biological conditions selected by the evolutionary process over millions of years. De Waal argues that the principle of parsimony (the least amount of sufficient explanation wins-also known as Ockham’s Razor) requires us to assume that ape action and human action have a shared ancestry, just as our bodies have a shared ancestry.

Beyond the argument for a shared biological ancestry for human and primate behavior, de Waal offers other useful resources for thinking about morality. Responding to the idea that humans are fundamentally individualistic and selfish, conditions supposedly bequeathed to them by an evolutionary process driven by the survival of the fittest, de Waal argues that this characterization of humans is not at all natural. Instead, “fitness” in nature is most often achieved through cooperation rather than direct competition. Thus, those traits that improve the ability of a species to cooperate improve its chances of survival.

De Waal also notes that in nature cooperation (and so morality) develops as a group phenomenon, but not a universal one. Thus, the same evolutionary process that developed our moral capacities also developed our capacity for war. De Waal discusses this irony at length in Our Inner Ape when he shows how human beings demonstrate a unique combination of traits related to power, sex, and violence, traits also found in our two closest ape ancestors: bonobos and chimpanzees.

Bonobos are an endangered species of ape. They live on the south bank of the Congo River in a region of the Democratic Republic of Congo (formerly Zaire) about the size of England. While we have known about bonobos since 1929, it is not their relative isolation that has kept them out of our textbooks and children’s stories. Rather, they have likely remained unknown to most because of the challenges posed by their social habits and, above all, by their sexuality.

Bonobos live most of their lives in trees, their leadership is matriarchal, and they are almost entirely nonviolent, highly social, and strikingly pansexual. Bonobos engage in sex much more often than they need to for the purposes of reproduction (just like human beings). They use sexuality to show affection and to resolve conflicts, whether between individuals or groups. Self-gratification and same-sex activity are common. Recently, genetic research has shown that humans share with bonobos a “microsatellite” of DNA related to sociality that is absent in chimpanzees.

Chimpanzees are male-hierarchical and extraordinarily violent both within and between groups. Sexuality for chimps is primarily a matter of reproduction, but it can also be used to express domination. Because male chimps try to restrict female sexuality, they are also more confident about paternity. Killing the newborn of a rival is not uncommon among chimps (something male bonobos could not do, because females deliberately confuse paternity by engaging in sex with more than one male). The grim character of a male chimp’s life is demonstrated by the fact that male-female ratios are equal at birth, but as adults female chimps outnumber males by two to one. (Male-female ratios remain equal among bonobos throughout their lifespan.)

For de Waal, humans are “bipolar” apes. We share the sociality (and much of the sexuality) of bonobos with the competitive violence of chimpanzees. De Waal reaches no normative conclusions from his comparison of human beings with bonobos, chimpanzees, and other primates. He does not urge us to be more like one or the other, nor does he argue that our morality is determined by our evolutionary heritage. He clearly recognizes that human morality is far more cognitively evolved and complex than that of apes. Yet he also finds that much of morality is a post hoc phenomenon, designed to provide conceptual justification for instinctive dispositions-dispositions that are entirely to be expected given our biological ancestry.

The idea that the origins of human morality have been produced by natural selection poses no challenge to the conclusion that the hand of God is at work in evolution, although it certainly challenges the idea that it is morality that separates humans from other animals. When one sees the hand of God in evolution, one also rejects any tidy division of territory between science and religion, fact and value. From a God-directed viewpoint, no fact of nature is fully understood apart from its God-given “final cause.” If the “end,” or telos, of something must be understood in order to understand the nature of that thing, the separation of “is” from “ought” dissolves. By emphasizing the continuity rather than the discontinuity between human morality and primate behavior, Frans de Waal provides numerous opportunities to reflect on how the hand of God might have been molding human character even before humans arrived on the scene.

Published in the 2007-12-21 issue: 

Joe Pettit is an assistant professor in the Department of Philosophy and Religious Studies at Morgan State University in Baltimore.

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