Partners or Strangers? Cooperation, Monetary Trade, and the Choice of Scale of Interaction
实验发现，货币交换能帮助人们从小规模合作转向大规模合作；没有货币时，大规模合作容易崩溃，而稳定的货币体系能缓解策略不确定性，恢复合作效率。
We show that monetary exchange facilitates the transition from small to large-scale economic interactions. In an experiment, subjects chose to play an “intertemporal cooperation game” either in partnerships or in groups of strangers where payoffs could be higher. Theoretically, a norm of mutual support is sufficient to maximize efficiency through large-scale cooperation. Empirically, absent a monetary system, participants were reluctant to interact on a large scale; and when they did, efficiency plummeted compared to partnerships because cooperation collapsed. This failure was reversed only when a stable monetary system endogenously emerged: the institution of money mitigated strategic uncertainty problems.