De Waal describes the moral behaviors of primates and what we might infer about our common heritage of feeling that may be the basis for more sophisticated morality. De Waal discusses empathy and nurturing behaviors but emphasizes more the ‘interpersonal’ (inter-animal) skills that most young monkeys and apes acquire over their youth that enable them to get along with others and also to manage politically in the group. De Waal proposes that the concerns of the group include matters that correspond roughly to fairness and justice in human societies.
The starting point for de Waal’s book is the observation that many primate societies have quite elaborate social interactions; they are not the ruthless ‘dog-eat-dog’ world that popular interpretations of animal nature (and evolution) would lead many of us to expect. In fact many of these societies tolerate and even support handicapped individuals. Recent discoveries of skeletons with healed major fractures have confirmed that our human ancestors did the same. De Waal takes off from these examples of assistance to the weak to a broader discussion of whether we would consider some primate social behaviors to be moral behavior if we were talking about human beings rather than apes.
De Waal continues with a discussion of how primates form alliances with others, and whether these may fairly be described as ‘friendships’, rather than alliances of convenience (using others for our ends). It is clear that alliances are complex and often primates shift alliances according to who is more dominant at any one time; Females spend more time grooming dominant males than subordinate males. At the very least these facts suggest that primates are capable of political calculation and anticipating others' responses in times of stress. However some affiliations seem to persist for long periods through several shifts in the political winds, and seem to involve signs of genuine affection and pleasure in each other’s company. Furthermore most alliances occur between individuals of similar stations in life, (who are most likely to be direct competitors), which suggests some common interests, rather than political calculation, may promote these affiliations. In summary we may say that primates seem to have different relationships with different degrees of warmth and political calculation, rather like human beings.
The second chapter entitled ‘Sympathy’ discusses in more detail how apes care for their incapacitated and also discusses evidence for the other sense of ‘sympathy’ – understanding others’ motivations and feelings. De Waal discusses examples of how apes and monkeys treat handicapped members of their societies. Apes seem to act more humanely than monkeys. However even monkeys often react in ways that seem to make accommodation for others’ handicaps, such as tolerating breaches of etiquette from a blind conspecific that they would never tolerate from a normal monkey. He then discusses how apes (and elephants) respond to the death of one of their own. They maintain extended silence and low-key activity after such deaths; these behaviors would be interpreted in humans as grief or shock. These facts suggest that primates and elephants have a strong emotional response to death, especially of a close friend. De Waal also discusses the response to injury: again apes seem to make allowances for injured members, and expect less of them; monkeys do so to a lesser degree.
De Waal then does a quick survey of the experimental work showing that apes have some capacity to anticipate what other apes may know, and how other apes may react to what they know. In some situations apes try to manipulate what other apes perceive in order to forestall unpleasant reactions. We would call such behavior intentional deception if we saw human beings behaving this way.
The third chapter deals with social rules among primates and how they are enforced. We may think of primate societies as ‘Lord of the Flies’ situations where 'might makes right', and to some extent this is true (as it is true of our own societies). However there are also more broadly distributed social powers and sometimes apparent broad consensus on what constitutes acceptable behavior. This consensus limits the absolute power of the alpha male in some situations. It is true that the majority of rule enforcement is done by parents toward children and by dominants toward subordinates. However many dominants also intervene to break up fights between subordinates. And sometimes the whole troop will band together to prevent the alpha from beating up one of their members.
The fourth chapter discusses reciprocity and sharing. There is considerable evidence that among many animals, males compete for the privilege of taking risks for the benefit of the group. This is believed to pay off for them in that females are more attracted to males who take risks; but we cannot conclude that this is their felt motivation. Chimpanzees like to lead hunts but successful hunting depends on co-operation from several members of the troop, and somehow, despite the frenzy of excitement after a successful hunt, choice pieces always go to the hunters, and their female friends, even when the alpha male would like some. Chimpanzees and many (though not all) monkeys respect food-property rights: a dominant will not generally try to steal food from a subordinate, but this is not true of many other mammals. Generally chimpanzees remember sharing and reciprocate by either sharing or by other favors.
The fifth chapter discusses aggression and reconciliation. Although primates do threaten or actually hit one another fairly often (about as often as grade-school kids), they clearly feel the tension (as manifest by nervous behaviors like nail-biting), and usually try to 'make up' fairly quickly after a fight. Often high-ranking males are too 'proud' to make up, and the females play a major role in their reconciliations. The females will often groom one male and then when he starts to reciprocate, she will move over to the other and transfer the first male's hands to the back of the second male!
De Waal also discusses the evidence about population density and aggression in primates. Unlike the famous studies of crowding in rats, primates seem to work harder at maintaining the peace. There are many more appeasement gestures ('politeness'). However the tension is evident, and when social conventions do break down, the fights tend to be nastier and more injurious.
De Waal concludes by saying why he thinks all this is relevant to human behavior. As he points out in the beginning of this book, behavioral science can describe how our social behavior is constructed but cannot recommend that the ‘natural’ behaviors of primates are in fact ideals worth emulating. Critics of studies of primate ethics frequently mention the Naturalistic Fallacy: they say that it is impossible “to derive an ought from an is”. De Waal argues that (p39):
"Evolution has produced the requisites for morality: a tendency to develop social norms and enforce them, the capacities of empathy and sympathy, mutual aid and a sense of fairness, the mechanisms of conflict resolution, and so on."
How we put together these components of morality is up to us as self-conscious animals. However to put together an effective morality we must work with these basic building blocks of our nature. In De Waal's view the failure of so many ideologies - religious and secular - comes from supposing that some abstract conceptions of right and wrong can completely displace our biological nature.
De Waal concludes (p 218):