The tragedy of the commons is an economic theory that states that individuals acting independently and rationally according to self interest, behave contrary to the interests for the whole group, ultimately depleting a shared limited resource. In this conference, Juan Emilio Cárdenas shares his work on showing possibilities where individuals interact in laboratory game environments that emulate the commons condition. His goal is to explain why, in the real world, such individual rational interaction is possible without a resource depletion tragedy.

Common pool, or common property resources are resources whose nature makes it costly to exclude potential beneficiaries from their use. Users can subtract from a given stock, that risks overuse. Cárdenas uses CPR games, or common pool resource games, to model the possible congestion that arises from continual use of such resources. His team’s pioneer experiments have generated strong user databases for testing.

Among his conclusions, Cárdenas shows that groups participating in CPR games do not convert to full cooperation or full free-riding, using several strategies to subtract from the resource. In the end, several aspects of the experiment show that the common-pool resource is left often undepleted. Cárdenas believes a form of sampling equilibrium can be used to explain why individuals choose certain strategies in this repeated social dilemma, engaging in a certain level of partial cooperation that sustains the resource.