What are the origins of humans' capacity to represent social relations? We approached this question by studying human infants' understanding of social dominance as a stable relation. We presented infants with interactions between animated agents in conflict situations. Studies 1 and 2 targeted expectations of stability of social dominance. They revealed that 15-mo-olds (and, to a lesser extent, 12-mo-olds) expect an asymmetric relationship between two agents to remain stable from one conflict to another. To do so, infants need to infer that one of the agents (the dominant) will consistently prevail when her goals conflict with those of the other (the subordinate). Study 3 and 4 targeted the format of infants' representation of social dominance. In these studies, we found that 12-and 15-mo-olds did not extend their expectations of dominance to unobserved relationships, even when they could have been established by transitive inference. These results suggest that infants' expectation of stability originates from their representation of social dominance as a relationship between two agents rather than as an individual property. Infants' demonstrated understanding of social dominance reflects the cognitive underpinning of humans' capacity to represent social relations, which may be evolutionarily ancient, and may be shared with nonhuman species. cognitive development | naïve sociology | human evolution | social cognition | relational reasoning S ocial relations have two key properties that distinguish them from other social entities. First, unlike social interactions, relations are stable across relatively long time periods and variable situations (1). Second, unlike individual dispositions, such as traits, relations apply over at least two individuals. We report four studies that investigated these two key properties in human infants' representation of social dominance. Studies 1 and 2 focused on infants' expectation of social dominance's stability across time and situations. Studies 3 and 4 focused on whether infants represent social dominance as an individual property or as a relation. In line with other approaches in biology (2), cognitive science (3), and social sciences (4), we define dominance as the tendency to prevail when one's goals conflict with those of another agent. The goals of two agents "conflict" when the fulfillment of the goal of one of the agents would prevent the other agent from fulfilling her goal. For example, if individuals A and B both aim to acquire a resource, but only one of them can get it, then their goals conflict. Note also that the notion of "general tendency to prevail" does not specify the source of this capacity, and may map to notions, like "power" (4-6) or "social status" (7) in the literature. Dominance relations are characteristic to many animal species that live in social groups. In some species of nonhuman primates and in humans, individuals not only track who is dominant or subordinate to them, but also recognize the dominance relations of others. This capacity may appear early in human's ontogeny and phylogeny (3, 8, 9) . Assumptions of stability are likely to play a crucial role in the monitoring of others' dominance relations. They allow for (i) extracting dominance relations by observing social interactions, and (ii) applying dominance relations across situations. (i) Dominance relationships can be established on the basis of various cues (e.g., size, posture, physical aggression, age, and dominance and submission displays in nonhuman primates). These cues have some diagnostic value because they are causally related, in some way or another, to the capacity to prevail when two or more agents' goals conflict. Another way to infer dominance relations is simply to look for its direct manifestations, by monitoring who prevails when two agents have conflicting goals. In these cases, the observation of a given interaction is used to infer a stable social relation. This type of process is likely to be important to assess the validity of cues of dominance. For example, in nonhuman primates, cues such as size or age are sometimes misleading, because young and small individuals may achieve a high dominance position through their social alliances (2, 8) . Tracking who prevails when agents have conflicting goals may provide more reliable information about dominance relations than agents' size or age in the long term. (ii) To use social relationships efficiently, one also has to have expectations about their effect on social interactions. Forming these expectations for novel situations entails the assumption of stability through time, and consistency across situations, of dominance relationships. Studies 1 and 2 tested whether human infants (i) track which individuals prevail against others in the face of conflicting goals, and (ii) use this knowledge as a basis for inferences about the outcomes of future conflicts. We hypothesized that infants' understanding of goal-directed actions might be sufficient to identify situations in which agents' goals conflict: Infants can predict actions on the basis of goals and have some understanding of constraints limiting agents' actions (10). They also have some sensitivity to agents' failures in achieving their goals (11). These abilities might allow infants to track who prevails when the goals of two agents conflict. Studies 3 and 4 investigated the format of infants' representation of social dominance. The format of a representation specifies how the information it represents is rendered, meaning what aspects of the information are made explicit in the representation. It determines what stands for what (e.g., specifying a set of symbols and a set of rules for combining these symbols). These studies thus focused on what may be described as the algorithmic level (12) or syntactic aspects (13) of dominance processing. There are two likely candidates for the representational format of social dominance. It may be treated as a (i) stable individual property organized on an ordered scale, similar to the ones one may use to measure height, for example. In this view, a dominance level would be attached to each individual, and the dominance relation between two agents can be directly read off this scale by comparing their ranks. Alternatively, dominance may be represented as a (ii) relationship, organized into pairs of
Early research on the visual understanding of social interactions is rooted in the field of social and psychological sciences, studying the different types (e.g., Leary's circumplex, REF , and physical characteristics (e.g., the distance between two individuals, Hall 1966) of social relations.
Representation of stable social dominance relations by human infants
Proceedings of the National Academy of Sciences of the United States of America
Proceedings of the National Academy of Sciences of the United States of America
Psychology Medicine