Exploring cooperative norms to counter fragmented societies

A cross disciplinary approach integrating experiments, theory, and simulations

Abstract

In this paper, we focus on the indirect reciprocity norm, which is famous in the evolution of cooperation study as a principle that explains why cooperative behavior is observed, especially between strangers in modern society, and point out that the public assessment scheme assumed in previous theoretical studies cannot handle the diversified worldview assumed in a divided society, and explain the importance of analyzing with a private assessment scheme instead. Next, we summarize the findings of the analytical method, focusing on the results of our previous research, taking into account the advantages and disadvantages of each method: experiment, theory, and simulation. Finally, we extract some characteristics of the cooperative norm in a divided society. Specifically, (1) in a divided society, since each person may see the world differently, a norm of tolerance should be adopted when judging impressions of others. (2) By granting citizenship to those who cooperate unconditionally and coexisting with them, the norm of cooperation not only stabilizes society but also increases the rate of cooperation in society. (3) A policy of updating impressions should be adopted so that favorable impressions take precedence.