“A City for Pigs” portrays Plato as a systems modeler of a sustainable society. Plato’s argumentative methods, in the Republic especially, are favorably compared to techniques of computer simulation and to the heuristic objectives of game theory. Plato’s views about social cooperation in the use of common-pool resources, for example, are shown to be strikingly similar to conclusions reached via field studies by Nobel laureate Elinor Ostrom in Governing the Commons: The Evolution of Institutions for Collective Action (1990). Plato’s own homology, of city and soul, provides a compelling rationale for both individual and collective action vis-à-vis the environmental and social problems we still face today.