Self-organized institutions in evolutionary dynamical-systems game

Kenji Itao, Postdoctoral Fellow, RIKEN, Japan

Social institutions are systems of shared norms and rules that regulate people's behaviors, often emerging without external enforcement. They provide criteria to distinguish cooperation from defection and establish rules to sustain cooperation. While principles for successful institutions have been proposed, the mechanisms underlying their emergence remain poorly understood. To address this, we introduce the evolutionary dynamical-systems game theory that couples game actions with environmental dynamics and explores the evolution of cognitive frameworks for decision-making. We focus on common-pool resource management model, where resources grow naturally and are harvested. Players use decision-making functions to determine whether to harvest at each step, based on environmental and peer monitoring. After evolution, decision-making functions enable players to detect selfish harvesting and punish it by overharvesting, which degrades the environment. This process leads to the self-organization of norms that classify harvesting actions as cooperative, defective, or punitive. The emergent norms for "cooperativeness" and rules of punishment serve as institutions.