Human empathy is a critically important capacity, one that holds entire societies together and connects us with those whom we love and care about. It is far more fundamental to survival, I’d say, than knowing what others know. But since it belongs to the large submerged part of the iceberg—traits that we share with all mammals—it doesn’t garner the same respect. Moreover, empathy sounds emotional, something cognitive science tends to look down upon. Never mind that knowing what others want or need, or how best to please or assist them, is likely the original perspective taking, the kind from which all other kinds derive. It is essential for reproduction, since mammalian mothers need to be sensitive to the emotional states of their offspring, when they are cold, hungry, or in danger. Empathy is a biological imperative.16
Empathic perspective taking, defined by the father of economics, Adam Smith, as “changing places in fancy with the sufferer,” is well known outside of our species, including dramatic cases of apes, elephants, or dolphins helping one another under dire circumstances.17 Consider how an alpha male chimpanzee at a Swedish zoo saved the life of a juvenile. The juvenile had entangled himself in a rope and was choking to death. The male lifted him up (thus removing the rope’s pressure) and carefully unwrapped the rope from his neck. He thus demonstrated an understanding of the suffocating effect of ropes and knew what to do about it. Had he pulled at the juvenile or the rope, he only would have made things worse.
Two dolphins support a third by taking her between them. They buoy the stunned victim so that her blowhole is above the surface, whereas their own blowholes are submerged. After Siebenaler and Caldwell (1956).
I speak of targeted helping, which is assistance based on an appreciation of the other’s precise circumstances. One of the oldest reports in the scientific literature concerns an incident, in 1954, off the coast of Florida. During a capture expedition for a public aquarium, a stick of dynamite was set off under the water surface near a pod of bottlenose dolphins. As soon as one stunned victim surfaced, heavily listing, two other dolphins came to its aid: “One came up from below on each side, and placing the upper lateral part of their heads approximately beneath the pectoral fins of the injured one, they buoyed it to the surface in an apparent effort to allow it to breathe while it remained partially stunned.” The two helpers were submerged, which meant that they couldn’t breathe during the entire effort. The pod remained nearby and waited until their companion recovered, after which they all fled in a hurry, taking tremendous leaps.18
Another case of targeted helping occurred one day at Burgers’ Zoo. After having cleaned the indoor hall and before releasing the chimps, the keepers hosed out all the rubber tires and hung them one by one on a horizontal log extending from the climbing frame. Upon seeing the tires, female Krom wanted one in which some water remained. The chimps often use tires as vessels to drink from. Unfortunately, this particular tire was at the end of the row, with multiple heavy tires hanging in front of it. Krom pulled and pulled at the one she wanted but was unable to move it. She worked in vain on this problem for over ten minutes, ignored by everyone except Jakie, a seven-year-old that she had taken care of as a juvenile. As soon as Krom gave up and walked away, Jakie approached the scene. Without hesitation he pushed the tires off the log one by one, beginning with the front one, followed by the second in the row, and so on, as any sensible chimp would. When he reached the last tire, he carefully removed it so that no water was spilled and carried it straight to his aunt, placing it upright in front of her. Krom accepted his present without any special acknowledgment and was already scooping up water with her hand when Jakie left.19
Having gone over numerous incidents of insightful assistance in The Age of Empathy, I am pleased that there are now finally controlled experiments.20 For example, at the PRI where Ayumu lives, two chimps were placed side by side while one had to guess what kind of tool the other needed to reach attractive food. The first chimp had a choice between a range of tools—such as a straw to suck up juice or a rake to move food closer—only one of which would work for her partner. She’d need to look at and judge her partner’s situation before handing her the most useful tool through a window. This is indeed what the chimps did, showing a capacity to grasp the specific needs of others.21
The next question is, do primates recognize one another’s internal states, such as the difference between a partner who is hungry and one who is sated? Would you give up precious food for someone who has just eaten a big meal right in front of you? This is the question Japanese primatologist Yuko Hattori asked the monkeys in our capuchin colony.
Capuchins can be quite generous and are great social eaters, often sitting in clusters munching together. When a pregnant female hesitates to descend to the floor to collect her own fruits (being arboreal, these monkeys feel safer higher up), we have seen other monkeys grab more than they need and bring handfuls of food up to her. In the experiment, we separated two monkeys with mesh wide enough to stick their arms through, while one of them received a small bucket with apple slices. Under these circumstances, the provisioned monkey often brings food to its empty-handed partner. They sit next to the mesh partition and let the other one reach through to take food out of their hands or mouth, sometimes actively pushing it in their direction. This is remarkable, because the circumstances allow the possessor to avoid sharing altogether by staying away from the mesh. We found one exception to their generosity, however: if their partner had just eaten, the monkeys became stingy. Of course, this could be due to a sated partner being less interested in food, but the monkeys were stingy only if they had actually seen their partner eat. A partner that had been fed out of sight was treated as generously as any other. Yuko concluded that the monkeys judged the need, or lack thereof, of their companions based on what they had seen them eat.22