Do Apes Read Minds?: Toward a New Folk Psychology

Chapter 11. Social Intelligence and the Evolution of Theory of Mind

11 Social Intelligence and the Evolution of Theory of Mind If a social animal is to become—as it must become—one of “Nature’s psychologists” it must come up with the appropriate ideology for doing psychology; it must develop a fitting set of concepts and a fitting logic for dealing with a unique and uniquely elusive portion of reality. —Nicholas Humphrey The Social Intelligence Hypothesis Humans can do a lot socially without having to think about others as receptacles for beliefs and desires. Yet most adult humans are able to consider people’s mental content. If we can accomplish most of our social goals without ascribing propositional content—without mindreading— why is this skill so widespread? Why is it that attributing propositional attitudes is ubiquitous among adult humans? As young children, before we have the set of attitude concepts and the fitting logic that connects those concepts to action, we are still able to predict behavior, explain behavior, make judgments about the acceptability of behavior, coordinate behavior, and so forth. I have argued that we are even able to act deceptively and predict behavior when others have false beliefs without appealing to any representational belief concept. But these claims fly in the face of what has long been given as an evolutionary story about the function of the ability to attribute beliefs and desires. The Social Intelligence Hypothesis provides a well-received answer about the evolution of our ability to attribute propositional attitudes. Varieties of this hypothesis suggest that we must attribute propositional attitudes to succeed in a complex social environment. The hypothesis, which originates with Alison Jolly (1966) and Nicholas Humphrey (1976), attempts to explain the perceived difference in intelligence between species and at first focused on the differences between primates and other taxa. 216 Chapter 11 The difference was mysterious, since while many activities in primates’ daily lives require sophisticated cognitive ability (e.g., navigating, processing food, remembering what food is available when), these tasks are not unique to the primates and other species who are considered to have sophisticated cognitive abilities, so ecological demands could not alone account for the difference in cognitive capacity between species.1 What could account for the difference is the corresponding complexity of these species’ social environments, or so Humphrey and Jolly independently proposed. Apes and monkeys live in intricate social groups that require substantial cognitive commitment; they must be able to recognize individuals (visually, aurally, and perhaps via other modalities as well), they must keep track of kin relations (especially in matrilineal species such as baboons), they must keep track of dominance relations and alliances, and they must be sensitive to possible defections. They must be able to remember who did what to whom and when, and who should care about it. In addition, they must decide what to do in the face of such actions and make judgments about whether they should, for example, challenge a dominant, join a coup, or court the dominant’s mate. They must decide when to let others know they have found food, and when to keep it for themselves. The family feuds, social climbing, and power struggles of primate social living make for much cognitive work, work that humans are all too familiar with. Not for nothing are the interactions of ape and monkey societies often portrayed as if they were pages from a novel. Researchers have called this primate political landscape Machiavellian (Whiten and Byrne 1988) and have likened it to something out of a Jane Austen novel (Cheney and Seyfarth 2007). In his book Chimpanzee Politics, Frans de Waal (1982) emphasizes the cognitive demands created by chimpanzees’ need for competition and deception. To thrive in this cutthroat environment is to come out on top of what has been called an evolutionary arms race (Whiten and Byrne 1988). According to Humphrey, the function of primate cognitive ability is to give individuals the ability to construct complex decision trees for predicting how one’s own behavior will affect others. Given the fierce primate social environment, making better predictions of behavior was instrumental for gaining greater resources; better predictions were used to better manipulate others’ behavior. As individuals gain a more sophisticated theory of social action and greater predictive success, they up the stakes for other members of their community, thus creating an evolutionary arms race. Since attributing propositional attitudes is needed for making the Social Intelligence and Evolution of Theory of...