A delightful book

"Our inner ape" by Frans De Wall is a popular science book without frills, no footnotes or end notes, not much effort to rigorously support some of the extrapolations. But there are indications of research that can lead to some verifications. Probably many other scientists will not agree with some of his conclusions. It is like a respected guest holding forth after dinner with a life time of interesting experiences. This article from science&spirit, written a few years before the book explains the book as well as any review (it unfortunately does not mention bonobos extensively discussed in the book). Excerpts:



"It is not hard to recognize the two pillars of human morality in the behavior of other primates. These pillars are elegantly summed up by the golden rule, which transcends the world’s cultures and religions. “Do unto others as you would have them do unto you” brings together empathy (attention to another’s feelings) and reciprocity (if others follow the same rule, you will be treated well). Human morality could not exist without empathy and reciprocity, tendencies that are widespread in other primates.

After one chimpanzee attacks another, for example, a bystander chimp will often go over to embrace the victim; we have documented hundreds of cases. Usually, the effect of such consolation is that screaming, yelping, and other signs of distress come to a stop. In fact, the tendency to reassure others is so strong that Nadia Kohts, a Russian scientist who raised a juvenile chimp nearly a century ago, said that if her charge escaped to the roof of her house, there was only one way to get him down. Holding out food would not do the trick, nor would shouts and threats of punishment. The only way would be for her to sit down and sob, as if she were in pain. Her suffering would prompt the young ape, a worried look on his face, to rush down from the roof and put an arm around her. This indicates the strength of the empathic tendency in our closest relatives.

Reciprocity, on the other hand, can be seen in experiments with captive primates. Before giving one chimpanzee food to divide with others, we measure spontaneous grooming in the colony: who grooms whom and for how long. Grooming is a pleasurable, relaxing activity, and being groomed is much appreciated. In our experiment, we found that one chimpanzee grooming another greatly increased the chance that the first would get food from the second. In other words, the chimpanzees remembered who had groomed them and paid them back later in the day. Like humans, apes seem quite capable of keeping track of incoming and outgoing favors.

Of course, these findings are not sufficient to speak of “morality,” but the tendencies observed in these primates fit what Scottish philosopher David Hume called the “moral sentiments.” Adding enforced social norms, our species turned the moral sentiments into an elaborate system that tells us how we ought to treat others and how we ought to promote the interests of the community."
A more recent book "Primates and philosophers" (which I have not yet seen) contains also discussions by other thinkers.