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Rise of the Planet of the Apes?

Trent Horn


In the study conducted at Georgia State University (which has been covered on websites such as CNN), scientists tested chimps with what they call the “ultimatum game.” The game has been played in cultures worldwide and involves three roles: the experimenter, the proposer, and the respondent. In the game, the experimenter offers the proposer and the respondent a prize (like money or food) that can be shared.

The respondent must accept the proposer’s division; otherwise neither player gets any part of the prize. The proposer is allowed to make the offer to the respondent, and when humans are the proposers the offer is usually half the prize. Most of us would probably be insulted if we were offered less than half. In the name of fairness, an even offer is usually made.

In light of this, researchers wondered if they could replicate anecdotal reports of chimpanzees in the wild exhibiting so-called fairness. The authors of the study recall one such report as follows:

In one example, an adolescent female broke up a fight between two juveniles over a leafy branch. The female broke the branch in two and then handed half to each juvenile without taking any for herself. Goodall [also] reported an interaction between two males, one of whom was in possession of meat. After repeated begging, the male without the meat threw a “violent tantrum.” Following this, the meat possessor ripped the prey in half and gave a portion to the second male.

The current experiments showed that chimps tend to split the prize evenly in the same manner as human children. The authors conclude that “humans and chimpanzees show similar preferences regarding reward division, suggesting a long evolutionary history to the human sense of fairness.”

Do the Right Thing

Can we conclude that chimps have a sense of morality based on the ultimatum game? At most, we can conclude that chimpanzees know that cooperation can yield better results for everyone. But I don’t think we can conclude that chimpanzees are moral creatures.

First, morality is about doing what’s right, not about doing what is most efficient or beneficial. The behaviors exhibited in the ultimatum game can easily be explained by humans and chimps trying to maximize their winnings. Even a chimp can figure out that half a prize is better than none at all.

In the anecdotal examples of chimps sharing in the midst of fights or tantrums, the “sharing” is merely a means to stop a potentially violent situation from escalating and so is more self-centered than other-directed.

Second, humans often display altruistic techniques that go far beyond what we see in the animal kingdom. Consider the case of Arland D. Williams Jr., who allowed other passengers on Air Florida Flight 90 to be rescued ahead of him after the plane crashed in the Potomac River.

The wreckage shifted before Williams could be rescued, and he ultimately gave his life so strangers could live. I’d like to see a study that shows some chimps are willing to let others go ahead of them if they are being chased by a crocodile.

Evil Animals?

Third, if we really thought chimps were moral agents, then why don’t we say chimps that maul people’s faces are evil? We say those chimps are operating on instinct and so they don’t deserve moral blame because they didn’t choose their behavior. But we do blame and condemn humans as evil when they choose to maul someone’s face (I’m looking at you Hannibal Lecter!).

This is because humans are the only primates who can recognize the existence of moral facts. These facts are true statements about morality such as “Rape is wrong” or “You ought to increase the well-being of conscious creatures.” These facts tell us how we ought to behave. Period.

In his book The Atheist’s Guide to Reality, philosopher Alex Rosenberg accepts that it would be radically unlikely for us to randomly evolve behaviors that also happened to correspond with moral rules like “Rape is wrong” that simply exist “out there” in an abstract realm. As a result, Rosenberg is a nihilist who says that morality is simply a human convention and has no real existence of its own.

But if moral facts really do exist, if some things really are just wrong even if they have an evolutionary advantage for our species (like parents drowning disabled infants), then this points to the existence of an objective ground for morality that does not change and provides the source of our moral obligations. Plato called this being “the Good”; the rest of us know this reality simply as God.


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