Primates and Philosophers_How Morality Evolved

by Frans de Waal

  Some scientists have objected, however:

  It is frequently said that people endorse such hypotheses [about human altruism] because they want the world to be a friendly and hospitable place. The defenders of egoism and individualism who advance this criticism thereby pay themselves a compliment; they pat themselves on the back for staring reality squarely in the face. Egoists and individualists are objective, they suggest, whereas proponents of altruism and group selection are trapped by a comforting illusion. (Sober and Wilson 1998: 8–9)

  These back-and-forth arguments about how to reconcile everyday human kindness with evolutionary theory seem an unfortunate legacy of Huxley, who had a poor understanding of the theory that he so effectively defended against its detractors. In the words of Mayr (1997: 250): “Huxley, who believed in final causes, rejected natural selection and did not represent genuine Darwinian thought in any way It is unfortunate, considering how confused Huxley was, that his essay [on ethics] is often referred to even today as if it were authoritative.”

  It should be pointed out, though, that in Huxley’s time there was already fierce opposition to his ideas (Desmond 1994), some of which came from Russian biologists, such as Petr Kropotkin. Given the harsh climate of Siberia, Russian scientists traditionally were far more impressed by the battle of animals against the elements than against each other, resulting in an emphasis on cooperation and solidarity that contrasted with Huxley’s dog-eat-dog perspective (Todes 1989). Kropotkin’s (1972 [1902]) Mutual Aid was an attack on Huxley, but written with great deference for Darwin.

  Although Kropotkin never formulated his theory with the precision and evolutionary logic available to Trivers (1971) in his seminal paper on reciprocal altruism, both pondered the origins of a cooperative, and ultimately moral, society without invoking false pretense, Freudian denial schemes, or cultural indoctrination. In this they proved the true followers of Darwin.

  DARWIN ON ETHICS

  Evolution favors animals that assist each other if by doing so they achieve long-term benefits of greater value than the benefits derived from going it alone and competing with others. Unlike cooperation resting on simultaneous benefits to all parties involved (known as mutualism), reciprocity involves exchanged acts that, while beneficial to the recipient, are costly to the performer (Dugatkin 1997). This cost, which is generated because there is a time lag between giving and receiving, is eliminated as soon as a favor of equal value is returned to the performer (for treatments of this issue since Trivers 1971, see Axelrod and Hamilton 1981; Rothstein and Pierotti 1988; Taylor and McGuire 1988). It is in these theories that we find the germ of an evolutionary explanation of morality that escaped Huxley.

  It is important to clarify that these theories do not conflict by any means with popular ideas about the role of selfishness in evolution. It is only recently that the concept of “selfishness” has been plucked from the English language, robbed of its vernacular meaning, and applied outside of the psychological domain. Even though the term is seen by some as synonymous with self-serving, English does have different terms for a reason. Selfishness implies the intention to serve oneself, hence knowledge of what one stands to gain from a particular behavior. A vine may be self-serving by overgrowing and suffocating a tree; but since plants lack intentions, they cannot be selfish except in a meaningless, metaphorical sense. Unfortunately, in complete violation of the term’s original meaning, it is precisely this empty sense of “selfish” that has come to dominate debates about human nature. If our genes are selfish, we must be selfish, too, is the argument one often hears, despite the fact that genes are mere molecules, and hence cannot be selfish (Midgley 1979).

  It is fine to describe animals (and humans) as the product of evolutionary forces that promote self-interests so long as one realizes that this by no means precludes the evolution of altruistic and sympathetic tendencies. Darwin fully recognized this, explaining the evolution of these tendencies by group selection instead of the individual and kin selection favored by modern theoreticians (but see, e.g., Sober and Wilson 1998; Boehm 1999). Darwin firmly believed his theory capable of accommodating the origins of morality and did not see any conflict between the harshness of the evolutionary process and the gentleness of some of its products. Rather than presenting the human species as falling outside of the laws of biology, Darwin emphasized continuity with animals even in the moral domain:

  Any animal whatever, endowed with well-marked social instincts, the parental and filial affections being here included, would inevitably acquire a moral sense or conscience, as soon as its intellectual powers had become as well developed, or nearly as well developed, as in man. (Darwin 1982 [1871]: 71–72)

  It is important to dwell on the capacity for sympathy hinted at here and expressed more clearly by Darwin elsewhere (e.g., “Many animals certainly sympathize with each other’s distress or danger” [Darwin 1982 (1871): 77]), because it is in this domain that striking continuities exist between humans and other social animals. To be vicariously affected by the emotions of others must be very basic, because these reactions have been reported for a great variety of animals and are often immediate and uncontrollable. They probably first emerged with parental care, in which vulnerable individuals are fed and protected. In many animals they stretch beyond this domain, however, to relations among unrelated adults (section 4 below).

  In his view of sympathy, Darwin was inspired by Adam Smith, the Scottish moral philosopher and father of economics. It says a great deal about the distinctions we need to make between self-serving behavior and selfish motives that Smith, best known for his emphasis on self-interest as the guiding principle of economics, also wrote about the universal human capacity of sympathy:

  How selfish soever man may be supposed, there are evidently some principles in his nature, which interest him in the fortune of others, and render their happiness necessary to him, though he derives nothing from it, except the pleasure of seeing it. (Smith 1937 [1759]: 9)

  The evolutionary origin of this inclination is no mystery. All species that rely on cooperation—from elephants to wolves and people—show group loyalty and helping tendencies. These tendencies evolved in the context of a close-knit social life in which they benefited relatives and companions able to repay the favor. The impulse to help was therefore never totally without survival value to the ones showing the impulse. But, as so often, the impulse became divorced from the consequences that shaped its evolution. This permitted its expression even when payoffs were unlikely, such as when strangers were beneficiaries. This brings animal altruism much closer to that of humans than usually thought, and explains the call for the temporary removal of ethics from the hands of philosophers (Wilson 1975: 562).

  Personally, I remain unconvinced that we need group selection to explain the origin of these tendencies—we seem to get quite far with the theories of kin selection and reciprocal altruism. Moreover, there is so much intergroup migration (hence gene flow) in nonhuman primates that the conditions for group selection do not seem fulfilled. In all of the primates, the younger generation of one sex or another (males in many monkeys, females in chimpanzees and bonobos) tends to leave the group to join neighboring groups (Pusey and Packer 1987). This means that primate groups are far from genetically isolated, which makes group selection unlikely.

  In discussing what constitutes morality, the actual behavior is less important than the underlying capacities. For example, instead of arguing that food-sharing is a building block of morality, it is rather the capacities thought to underlie food-sharing (e.g., high levels of tolerance, sensitivity to others’ needs, reciprocal exchange) that seem relevant. Ants, too, share food, but likely based on quite different urges than those that make chimpanzees or people share (de Waal 1989a). This distinction was understood by Darwin, who looked beyond the actual behavior at the underlying emotions, intentions, and capacities. In other words, whether animals are nice to each other is not the issue, nor does it matter much whether their behavior fits o
ur moral preferences or not. The relevant question rather is whether they possess capacities for reciprocity and revenge, for the enforcement of social rules, for the settlement of disputes, and for sympathy and empathy (Flack and de Waal 2000).

  This also means that calls to reject Darwinism in our daily lives so as to build a moral society are based on a profound misreading of Darwin. Since Darwin saw morality as an evolutionary product, he envisioned an eminently more livable world than the one proposed by Huxley and his followers, who believe in a culturally imposed, artificial morality that receives no helping hand from human nature. Huxley’s world is by far the colder, more terrifying place.

  EDWARD WESTERMARCK

  Edward Westermarck, a Swedish Finn who lived from 1862 until 1939, deserves a central position in any debate about the origin of morality, since he was the first scholar to promote an integrated view including both humans and animals and both culture and evolution. That his ideas were underappreciated during his lifetime is understandable, because they flew in the face of the Western dualistic tradition that pits body against mind and culture against instinct.

  Westermarck’s books are a curious blend of dry theorizing, detailed anthropology, and secondhand animal stories. The author was eager to connect human and animal behavior, but his own work focused entirely on people. Since at the time little systematic research on animal behavior existed, he had to rely on anecdotes, such as the one of a vengeful camel that had been excessively beaten on multiple occasions by a fourteen-year-old camel driver for loitering or turning the wrong way. The camel passively took the punishment; but a few days later, finding itself unladen alone on the road with the same driver, “seized the unlucky boy’s head in its monstrous mouth, and lifting him up in the air flung him down again on the earth with the upper part of the skull completely torn off, and his brains scattered on the ground” (Westermarck 1912 [1908]: 38).

  We should not discard such unverified reports out of hand: stories of delayed retaliation abound in the zoo world, especially about apes and elephants. We now have systematic data on how chimpanzees punish negative actions with other negative actions (called a “revenge system” by de Waal and Luttrell 1988), and how a macaque attacked by a dominant member of its troop will turn around to redirect aggression against a vulnerable younger relative of its attacker (Aureli et al. 1992). These reactions fall under Westermarck’s retributive emotions, but for him the term “retributive” went beyond its usual connotation of getting even. It also covered positive emotions, such as gratitude and the repayment of services. Depicting the retributive emotions as the cornerstone of morality, Westermarck weighed in on the question of its origin while anticipating modern discussions of evolutionary ethics.

  Westermarck is part of a long tradition, going back to Aristotle and Thomas Aquinas, which firmly anchors morality in the natural inclinations and desires of our species (Arnhart 1998, 1999). Emotions occupy a central role; it is well known that, rather than being the antithesis of rationality, emotions aid human reasoning. People can reason and deliberate as much as they want, but, as neuroscientists have found, if there are no emotions attached to the various options in front of them, they will never reach a decision or conviction (Damasio 1994). This is critical for moral choice, because if anything morality involves strong convictions. These convictions don’t—or rather can’t—come about through a cool rationality: they require caring about others and powerful “gut feelings” about right and wrong.

  Westermarck (1912 [1908], 1917 [1908]) discusses, one by one, a whole range of what philosophers before him, most notably David Hume (1985 [1739]), called the “moral sentiments.” He classified the retributive emotions into those derived from resentment and anger, which seek revenge and punishment, and those that are more positive and prosocial. Whereas in his time few animal examples of the moral emotions were known—hence his reliance on Moroccan camel stories—we know now that there are many parallels in primate behavior. He also discusses “forgiveness,” and how the turning of the other cheek is a universally appreciated gesture. Chimpanzees kiss and embrace after fights, and these so-called reconciliations serve to preserve peace within the community (de Waal and van Roosmalen 1979). A growing literature exists on conflict resolution in primates and other mammals (de Waal 1989b, 2000; Aureli and de Waal 2000; Aureli et al. 2002). Reconciliation may not be the same as forgiveness, but the two are obviously related.

  Westermarck also sees protection of others against aggression as resulting from what he calls “sympathetic resentment,” thus implying that this behavior rests on identification and empathy with the other. Protection against aggression is common in monkeys and apes and in many other animals, who stick up for their kin and friends. The primate literature offers a well-investigated picture of coalitions and alliances, which some consider the hallmark of primate social life and the main reason that primates have evolved such complex, cognitively demanding societies (e.g., Byrne and Whiten 1988; Harcourt and de Waal 1992; de Waal 1998 [1982]).

  Similarly, the retributive kindly emotions (“desire to give pleasure in return for pleasure”: Westermarck 1912 [1908]: 93) have an obvious parallel in what we now call reciprocal altruism, such as the tendency to repay in kind those from whom assistance has been received. Westermarck adds moral approval as a retributive kindly emotion, hence as a component of reciprocal altruism. These views antedate the discussions about “indirect reciprocity” in the modern literature on evolutionary ethics, which revolve around reputation building within the larger community (e.g., Alexander 1987). It is truly amazing to see how many issues brought up by contemporary authors are, couched in somewhat different terms, already present in the writings of this Swedish Finn of a century ago.

  The most insightful part of Westermarck’s work is perhaps where he tries to come to grips with what defines a moral emotion as moral. Here he shows that there is more to such emotions than raw gut feeling, as he explains that they “differ from kindred non-moral emotions by their disinterestedness, apparent impartiality, and flavour of generality” (Westermarck 1917 [1908]: 738–39). Emotions such as gratitude and resentment directly concern one’s own interests—how one has been treated or how one wishes to be treated— hence they are too egocentric to be moral. Moral emotions ought to be disconnected from one’s immediate situation: they deal with good and bad at a more abstract, disinterested level. It is only when we make general judgments of how anyone ought to be treated that we can begin to speak of moral approval and disapproval. It is in this specific area, famously symbolized by Smith’s (1937 [1759]) “impartial spectator,” that humans seem to go radically further than other primates.

  Sections 4 and 5 discuss continuity between the two main pillars of human morality and primate behavior. Empathy and reciprocity have been described as the chief “prerequisites” (de Waal 1996) or “building blocks” of morality (Flack and de Waal 2000)—they are by no means sufficient to produce morality as we know it, yet they are indispensable. No human moral society could be imagined without reciprocal exchange and an emotional interest in others. This offers a concrete starting point to investigate the continuity that Darwin envisioned. The debate about Veneer Theory is fundamental to this investigation since some evolutionary biologists have sharply deviated from the idea of continuity by presenting morality as a sham so convoluted that only one species—ours—is capable of it. This view has no basis in fact, and as such stands in the way of a full understanding of how we became moral (table 1). My intention here is to set the record straight by reviewing actual empirical data.

  ANIMAL EMPATHY

  Evolution rarely throws out anything. Structures are transformed, modified, co-opted for other functions, or “tweaked” in another direction—descent with modification, as Darwin called it. Thus, the frontal fins of fish became the front limbs of land animals, which over time turned into hoofs, paws, wings, hands, and flippers. Occasionally, a structure loses all function and becomes superfluous, but this is a gradual process
, often ending in rudimentary traits rather than disappearance. We find tiny vestiges of leg bones under the skin of whales and remnants of a pelvis in snakes.

  This is why to the biologist, a Russian doll is such a satisfying plaything, especially if it has a historical dimension. I own a doll that shows Russian President Vladimir Putin on the outside, within whom we discover, in this order, Yeltsin, Gorbachev, Brezhnev, Kruschev, Stalin, and Lenin. Finding a little Lenin and Stalin within Putin will hardly surprise most political analysts. The same is true for biological traits: the old always remains present in the new.

  TABLE 1

  Comparison of Veneer Theory and the View of Morality as an Outgrowth of the Social Instincts

  This is relevant to the debate about the origin of empathy, since the psychologist tends to look at the world through different eyes than the biologist. Psychologists sometimes put our most advanced traits on a pedestal, ignoring or even denying simpler antecedents. They thus believe in saltatory change, at least in relation to our own species. This leads to unlikely origin stories, postulating discontinuities with respect to language, which is said to result from a unique “module” in the human brain (e.g., Pinker 1994), or with respect to human cognition, which is viewed as having cultural origins (e.g., Tomasello 1999). True, human capacities reach dizzying heights, such as when I understand that you understand that I understand, et cetera. But we are not born with such “reiterated empathy,” as phenomenologists call it. Both developmentally and evolutionarily, advanced forms of empathy are preceded by and grow out of more elementary ones. In fact, things may be exactly the other way around. Instead of language and culture appearing with a Big Bang in our species and then transforming the way we relate to each other, Greenspan and Shanker (2004) propose that it is from early emotional connections and “proto conversations” between mother and child (cf. Trevarthen 1993) that language and culture sprang. Instead of empathy being an endpoint, it may have been the starting point.