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We present a tragedy of the commons model in which individuals have no a priori knowledge of the immediate consequences of their actions: Each agent chooses actions using a simple neural network, which it gradually modifies to more closely imitate those of its wealthier neighbors. For a small commons size, the model leads neither to the tragedy of complete resource exhaustion nor to complete cooperation, but instead to the emergence of polarized ‘economic classes’ of poor and altruistic agents living amongst rich and greedy ones. The tragedy does emerge with larger commons sizes; we found that adding a degree of enforced local sharing among neighbors staves off tragedy there, and once again the economic stratification emerges. Though simple, the model displays a surprising range of dynamic behaviors at multiple temporal and spatial scales, as two fundamentally conflicting ‘ideologies’ war for control of agent behavior.