David Bollier in Evonomics:
“Picture a pasture open to all.”
For at least a generation, the very idea of the commons has been marginalized and dismissed as a misguided way to manage resources: the so-called tragedy of the commons. In a short but influential essay published in Science in 1968, ecologist Garrett Hardin gave the story a fresh formulation and a memorable tagline.
“The tragedy of the commons develops in this way,” wrote Hardin, proposing to his readers that they envision an open pasture:
It is to be expected that each herdsman will try to keep as many cattle as possible in the commons. Such an arrangement may work reasonably satisfactorily for centuries because tribal wars, poaching and disease keep the numbers of both man and beast well below the carrying capacity of the land. Finally, however, comes the day of reckoning, that is, the day when the long-desired goal of social stability becomes a reality. At this point, the inherent logic of the commons remorselessly generates tragedy. As a rational being, each herdsman seeks to maximize his gain. Explicitly or implicitly, more or less consciously, he asks, “What is the utility to me of adding one more animal to my herd?”
The rational herdsman concludes that the only sensible course for him to pursue is to add another animal to his herd. And another…. But this is the conclusion reached by each and every rational herdsman sharing a commons. Therein is the tragedy. Each man is locked into a system that compels him to increase his herd with- out limit—in a world that is limited. Ruin is the destination toward which all men rush, each pursuing his own best interest in a society that believes in the freedom of the commons. Freedom in a commons brings ruin to all.
More here.