Dorothy L. Cheney and Robert M. Seyfarth on Monkey Cognition

We have argued that in order to succeed socially monkeys must be able to predict the behavior of others. To do this well they cannot rely on memorizing single interactions but must instead deal in abstractions, comparing the relationships that exist among others. For humans, the quest to predict behavior prompts us to search still further, for the factors that cause some relations to be different from others. A monkey that can compare social relationships is better able to predict the behavior of others than one who simply memorizes all the interactions he has observed. Vastly more powerful abilities to interpret other animals’ behavior accrue to the individual who can attribute motives to others and classify relationships on the basis of these motives. . . .

There are hints that nonhuman primates might occasionally attribute motives to one another. . . . Most examples, however, are anecdotal, and they are largely restricted to chimpanzees. Whether monkeys ever attribute states of mind to each other and whether they recognize that different states of mind are the cause of different social relationships, is an open question. In most cases, it is as easy to explain the behavior of monkeys in terms of learned behavioral contingencies as in terms of the attribution of mental states. . . . We have good evidence that monkeys are adept at understanding each others’ [sic] behavior and relationships; what remains to be determined is whether they are also adept at understanding each others’ [sic] minds.

(Dorothy L. Cheney and Robert M. Seyfarth, “The Representation of Social Relations by Monkeys,” chap. 7 in Animal Cognition, ed. C. R. Gallistel [Cambridge: The MIT Press, 1992], 167-96, at 191-2 [italics in original; parenthetical citations omitted] [essay first published in 1990])