A lineage explanation of human normative guidance: the coadaptive model of instrumental rationality and shared intentionality.

This paper aims to contribute to the existing literature on normative cognition by providing a lineage explanation of human social norm psychology. This approach builds upon theories of goal-directed behavioral control in the reinforcement learning and control literature, arguing that this form of control defines an important class of intentional normative mental states that are instrumental in nature. I defend the view that great ape capacities for instrumental reasoning and our capacity (or family of capacities) for shared intentionality coadapted to each other and argue that the evolution of this capacity has allowed the representation of social norms and the emergence of our capacity for normative guidance.

Children's developing metaethical judgments.

Human adults incline toward moral objectivism but may approach things more relativistically if different cultures are involved. In this study, 4-, 6-, and 9-year-old children (N=136) witnessed two parties who disagreed about moral matters: a normative judge (e.g., judging that it is wrong to do X) and an antinormative judge (e.g., judging that it is okay to do X). We assessed children's metaethical judgment, that is, whether they judged that only one party (objectivism) or both parties (relativism) could be right. We found that 9-year-olds, but not younger children, were more likely to judge that both parties could be right when a normative ingroup judge disagreed with an antinormative extraterrestrial judge (with different preferences and background) than when the antinormative judge was another ingroup individual. This effect was not found in a comparison case where parties disagreed about the possibility of different physical laws. These findings suggest that although young children often exhibit moral objectivism, by early school age they begin to temper their objectivism with culturally relative metaethical judgments.

The Role of Ontogeny in the Evolution of Human Cooperation.

To explain the evolutionary emergence of uniquely human skills and motivations for cooperation, Tomasello et al. (2012, in Current Anthropology 53(6):673-92) proposed the interdependence hypothesis. The key adaptive context in this account was the obligate collaborative foraging of early human adults. Hawkes (2014, in Human Nature 25(1):28-48), following Hrdy (Mothers and Others, Harvard University Press, 2009), provided an alternative account for the emergence of uniquely human cooperative skills in which the key was early human infants' attempts to solicit care and attention from adults in a cooperative breeding context. Here we attempt to reconcile these two accounts. Our composite account accepts Hrdy's and Hawkes's contention that the extremely early emergence of human infants' cooperative skills suggests an important role for cooperative breeding as adaptive context, perhaps in early Homo. But our account also insists that human cooperation goes well beyond these nascent skills to include such things as the communicative and cultural conventions, norms, and institutions created by later Homo and early modern humans to deal with adult problems of social coordination. As part of this account we hypothesize how each of the main stages of human ontogeny (infancy, childhood, adolescence) was transformed during evolution both by infants' cooperative skills "migrating up" in age and by adults' cooperative skills "migrating down" in age.