Tragedy of the Commons
A term used to illustrate the conflict between individual interests and the common good, based on the assumption that when individuals use a public good, they do not consider the impact – or externalities – of their use on the good itself; as a result, public resources become overexploited. The term was popularized by Garrett Hardin in his 1968 Science article “The Tragedy of the Commons,” which used a hypothetical example of English Commons, shared plots of grassland used by all livestock farmers in a village. In this hypothetical, each farmer keeps adding more livestock to graze on the Commons, because it costs him nothing to do so. In a few years, the soil is depleted by overgrazing, the Commons becomes unusable, and the village perishes.
Real life examples of the Tragedy of the Commons such as overfishing of sensitive fish populations. Like the grazing commons in Hardin’s paper, sensitive fish species where each individual fishing boat has an incentive to over fish until the population crashes, possible irrevocably, like the schools of sardines that were fished off the coast of Monterey or cod off the eastern seaboard. However, there are real life examples of people that used social norms to prevent over use or abuse of common resources such as imposed restrictions on fish size and strict rules on fishing seasons.