People can predict classmates’ cooperation better than chance, and cooperators befriend each other.

Evidence

A total of 122 students of six secondary school classes played an anonymous “Dictator Game” (see sect. 3 below), which functioned as a measure of cooperation. Afterwards and unannounced, the students had to estimate what their classmates’ decisions had been, and they did so better than chance. Sociometry revealed that the accuracy of predictions depended on social closeness. Friends (and also classmates who were disliked) were judged more accurately than others. Moreover, the more cooperative participants tended to be friends with one another. There are two prerequisites for the evolution of cooperation through social selection: the predictability of moral behavior and the mutual association of more cooperative individuals. These experimental results show that these prerequisites are typically satisfied. In a market of cooperative partners, the most cooperative individuals end up interacting with one another and enjoy more common good. — Nicolas Baumard, A mutualistic approach to morality, 34

Categorization

• XREF: Connects directly to the reading purpose: the predictability of moral behavior and association of cooperators underpin Baumard’s partner-choice account of ‘Big God’ religion that the reader is analyzing via Silence.
• DEFINE: The two prerequisites of social-selection cooperation — predictability and mutual association — are precisely defined here.