Norms and cultural learning in the N-player prisoner's dilemma

Social dilemmas are characterised by a choice between actions which are individually rational but collectively sub-optimal and actions which are better for the collective but leave individuals open to exploitation. Evolutionary game theory has been adopted to model the evolution of successive generations of agents playing a social dilemma game. In evolutionary simulations of N-player social dilemmas, cooperation rarely emerges. This paper investigates cultural evolution (via norms that are recorded as artefacts) as a means to increase the fitness of the society by allowing individual strategies to base their actions, not just on their genetic material, but also to take into consideration (by learning) evidence recorded as artefacts. In the first set of experiments, these norms are propagated vertically and we show that allowing cultural learning for a set of strategies in a small population can result in a stable and cooperative society. In the second set of preliminary experiments, agents are organised spatially according to a random graph and norms are spread horizontally.