Speaker: Julien Gagnon
Title: With God We Trust: Religion, Trust and Cooperation in Large-Scale Societies
The first aim of this paper is to revisit the puzzle of cooperation in large-scale societies. It proposes a game theoretic model showing how endogenous emotion-based punishment can sustain full cooperation when interactions are not repeated, provided that players' endogenous trust is high enough. The model is extended to allow for players' heterogeneity, in which case multiple stable equilibria of cooperation can coexist. The second aim of this paper is to explain how certain institutions may support trust and cooperation in large societies. It builds on the example of a religious group and shows that costly religious requirements may foster trust within a community, which in turn bolsters cooperation. When players are heterogeneous, the model shows that religion may also serve as signalling device to exclude defectors. Religion is thus shown to have a twofold role of trust coordination and signalling. This paper thus extends the signalling theory of religion. Finally, the model enables clear and tractable predictions about the levels of religious affiliation and participation within a society. Evidence of the model's implications is discussed.