Tragedy of the commons

A term referring to the theory that, when a group of people collectively own a resource, individuals acting in their personal self-interest will inevitably overtax and destroy the resource. According to the commons theory, each individual gains much more than he or she loses by overusing a commonly held resource, so its destruction is simply an inevitable consequence of normal and rational behavior. In the study of economics, this idea is known as the free rider problem. Human population growth is the issue in which the commons idea is most often applied: each individual gains personal security and wealth by producing many children. Even though each additional child taxes the global community's food, water, energy, and material resources, each family theoretically gains more than it loses for each additional child produced. Although the theory was first published in the nineteenth century, Garrett Hardin introduced it to modern discussions of population growth in a 1968 article published in the journal Science. Since that time, the idea of the tragedy of the commons has been a central part of population theory. Many people insist that the logic of the commons is irrefutable; others argue that the logic is flawed and the premises questionable. Despite debates over its validity, the theory of the commons has become an important part of modern efforts to understand and project population growth.

In its first published version, the idea of the commons was a scenario mapped out in mathematical logic and concerning common pasture land in an English village. In his 1833 essay, William Forster Lloyd described the demise of a common pasture through overuse. Up to that time, many English villages had a patch of shared pasture land, collectively owned, on which villagers could let their livestock graze. At the time of Lloyd's writing, however, many of these commons were being ruined through overgrazing . This destruction, he proposed, resulted from unchecked population growth and from the persistence of collectively held, rather than private, lands. In previous ages, said Lloyd, wars and plagues kept human and animal populations well below the maximum number the land could support. By the nineteenth century, however, England's population was climbing. More people were looking for room to graze more cattle, and they used common pasture because the resource was essentially free. Free use of a common resource, Lloyd concluded, leads directly to the ruin of that resource.

In his 1968 article, Garrett Hardin applied the same logical argument to a variety of natural amenities that we depend upon. Cattle, grazing on public lands in the American West, directly consume a common pasture owned by all Americans. Normal pursuit of increased capital leads ranchers to add as many cattle as they can, and much of the country's public lands are now severely denuded, gullied, and eroded from overgrazing. National parks such as Yosemite and Yellowstone are commonly held lands to which all Americans have free access. Each individual naturally wishes to maximize her or his vacation time, so that the collective result is congestion and pollution in the parks. The oceans represent the ultimate world commons. Private corporations and individual countries maximize their profit by catching as many fish as possible. In whaling , we have seen this practice effectively eliminate some species within a few decades. Other fisheries currently stand in danger of the same end.

Extrapolating his reasoning to arguments for population control, Hardin pointed out that if each family produces as many children as it can, then the inevitable collective result will be wholesale depletion of food, clean water, energy resources, and living space. Worldwide, quality of life will then diminish. Because we cannot increase the world's supply of water, energy, and space, argues Hardin, the only way to avoid this chain of events is to prevent population increases. Ideally, we need worldwide agreements to moderate individual childbearing activity, so that the cumulative demand on world resources will not exceed resource availability.

Critics dispute Hardin's thesis on a number of levels. The most important objection is that Lloyd and Hardin condemned the idea of the commons but that their examples did not involve real community resources. A commons, maintained over generations by a group of people for the benefit of the group, lasts because members of the group accept a certain amount of self-restraint in the interest of the community and because they know that self-restraint ensures the resource's survival. Peer pressure, respect for elders and taboos, fear of recrimination from neighbors, and consideration of neighbors' needs all reinforce individual restraint in a commons. All of these restraints rely upon a stable social structure and an understanding of commons management. In a stable society, individual survival depends upon the prosperity of one's neighbors, and every parent has an interest in ensuring that future generations will have access to necessary resources. Many such commons exist around the world today, especially in traditional villages in the developing world, where generational rules dictate the protection of grazing lands, water resources , fields, and forests.

In Lloyd's case study, industrialization, widespread eviction of tenant farmers to make way for sheep, and the introduction of capitalism had all disrupted the traditional social fabric of English villages. Uprooted families moving from village to village did not observe traditional rules. More importantly, many common pastures were being privatized by large landowners, leaving fewer acres of public land for village livestock to squeeze onto. The problem described in Lloyd's essay was, in fact, one of uncontrolled free access to a resource whose collective ownership had broken down. Likewise, ocean fisheries have generally been uncontrolled, unowned resources with no collectively enforced rules of restraint. American public grazing lands have rules of restraint, but they fail because of poor enforcement and inadequate development.

Many people also object to the implication of commons logic that a system of private property is superior to one of collectively held property. In criticizing village commons, Lloyd defended the actions of powerful landholders who could, on a whim, evict a community of tenant farmers. Commons logic holds that private landowners make better guardians of resources because they can see that their personal interest is directly served by careful management. However, evidence abounds that private owners frequently exploit and destroy resources much faster than groups do. Nineteenth century landowners, after removing farmers who had husbanded their land for generations, overstocked the country with sheep and clear-cut forests for lumber. Gullied pastures, lost wildlife habitat , and other environmental costs resulted. In the American timber industry, virtually all private old-growth forests have been cleared, their capital liquidated. Publicly held old growth, because it is expected to serve other needs beyond lumber production (wildlife habitat, recreation , watershed for communities, biological resources), has survived better than private forests. As a community, the people of the United States have imposed some rules and limitations on forest use that private landholders have not had. In a capitalist society, private landowners often benefit most by quickly liquidating natural resources , which allows them to move on to another area and another resource.

Where resources are precious or irreplaceable, collective guardianship is often the only way to ensure their maintenance. In villages from India to Zaire to the Philippines, community councils monitor the use of forests, water supplies, and crop lands. In developed countries, common and highly valued resources such as schools, public roadways, and parks have long been monitored and controlled by rules that restrain individual behavior and prevent destruction of those resources. Generally, everyone agrees not to block roads, burn schools, or vandalize parks because these resources benefit them all in some way. At the same time, no private individual could adequately maintain such resources. Collective responsibility and respect are necessary.

Finally, some critics argue that it is simplistic to assume that depletion results from population size, rather than uneven distribution of resources. Garrett Hardin chooses to direct his commons logic at large numbers of people using limited amounts of resources without considering the amount of resources used per person. Residents of the world's poorer regions counter that each of their children uses only 5% of the resources that an American child uses. The world can afford a great number of these children, they argue, and it could afford even more of them if people in wealthy countries drove fewer cars, ate less beef, and polluted less of the world's air and water. The deduction that breeding causes shortages, not rates of consumption, is hotly contested by those whose survival depends on the labor of their children.

Defenders of poorer segments of the world's population point out that social stability , including a fair distribution of resources, is more likely than population control to deter a global tragedy of the commons. As long as war and famine exist, and as long as the rich continue to exploit the labor and resources of the poor (an example of which is American support of the Guatemalan military structure so that we might buy coffee for three dollars a pound and bananas for 50 cents), reliable social structures cannot be rebuilt and responsible guardianship of the world's resources cannot be reestablished.

In the end, arguments for and against commons logic are based upon examples and interpretation. Logical proof, which the scenario set out to establish, remains elusive because the real world is very complex and because one's acceptance of both premises and conclusions depends upon one's political, economic, and social outlook.

[Mary Ann Cunningham Ph.D. ]

RESOURCES

PERIODICALS

Hardin, Garrett. "The Tragedy of the Commons." Science 162 (December 13, 1968): 1243–48.

"Whose Common Future?" Ecologist 22 (July/August 1992).

Tragedy of the Commons

BIBLIOGRAPHY

In 1968 the ecologist Garrett Hardin (1915-2003) published the article “The Tragedy of the Commons,” in which he argued that the problem raised by population growth had only a moral solution. His use of the word tragedy was meant to emphasize the inevitableness of destiny and the remorseless working of things. He used the celebrated example of a pasture open to all to illustrate what he considered to be a problem facing the human race in general.

Suppose that a pasture is used freely by herdsmen owning their cattle privately. Acting rationally and selfishly, each herdsman chooses the size of his herd so as to maximize his private gain. Adding one animal yields a positive component reflecting the proceeds from selling the animal. It also involves a cost: if pasture space is scarce, the additional animal results in overgrazing. However, that cost is shared by all herdsmen and is only minimally felt by the particular decision maker. The tragedy unfolds when all decision makers disregard the costs imposed on others, which leads all the herdsmen to own too many animals. Heavy overgrazing results, and the cattle are underfed and fetch low prices. In this scenario, herdsmen will add to their herd until they derive no benefit from the additional animal. This is called rent dissipation. With free access, the magic of Adam Smith’s (1723–1790) invisible hand does not work.

In “The Economic Theory of a Common Property Resource: The Fishery” (1954), H. Scott Gordon provided a technical analysis of the problem well before Hardin gave it celebrity. Gordon described a situation in which a private fisherman does not benefit from restraining his activity: the fish he leaves in the water is likely to be caught by some other fisherman. As a result, valuable fish stocks are often overfished, and fishermen are often poor. The collapse of the North Atlantic cod fishery at the end of the twentieth century, as well as the collapse of the Chilean anchovy fishery two decades earlier, are just two dramatic examples.

The particular conditions inducing waste and rent dissipation that are typical of the tragedy of the commons arise either progressively when populations increase their pressure on a common-access resource, or more suddenly when a resource is discovered or when some technological breakthrough makes its exploitation easier. This is why some such tragedies appear as historical events. For example, whales were not endangered before the introduction of harpoon guns reduced the cost of catching them at the same time that they had become valuable for uses other than food for Inuit. In the early twentieth century, oil was discovered and exploited in common pools in the United States. This led to overextraction as one operator rushed to exploit a pool before others could deplete it. In “The Simple Economics of Easter Island” (1998), Jim Brander and M. Scott Taylor interpret the rise and collapse of that island’s civilization as an instance of tragedy of the commons. Climate change is another example: emitters of greenhouse gases treat the atmosphere as an open-access resource, not taking into account the costs borne by present and future humans (not to mention other species).

While pervasive, is the tragedy of the commons inevitable, as implied by Hardin? Gordon’s analysis identifies common property as the culprit. Were the fishery controlled by a single owner who decided how much fish should be caught, that single owner would bear the consequences of overfishing privately and would properly weigh such costs against the benefits of higher current catches. The outcome would be Pareto efficient under perfect competition.

There are many examples of private property rights solving the tragedy of the commons. The enclosures episode which witnessed the construction of fences around previously open-access areas in eighteenth- and nineteenth-century England is a celebrated though disputed example. Coase’s theorem indicates that any system of property rights, by defining a framework for bargaining, will solve externality problems provided costs of transactions are negligible. In Governing the Commons (1990), Elinor Ostrom analyzes many instances where societies have devised institutions other than private property and markets to secure or induce efficient resource use.

A simple look at the organization of economic and social life shows many potential tragedies being avoided thanks to property rights or other social rules: We accept that we must pay for food that we buy in a supermarket; most of the time, cars do not get robbed while parked on the street; we do not freely cut trees in forests for firewood.

Yet solutions or improvements are not easy to come by. The creation or enforcement of property rights, whether private or otherwise, may be institutionally or technologically difficult. Ideally, property rights must be designed in such a way that they cause decision makers to act in the interest of society as a whole in the use of the resource. In many situations, this is not possible either because the required information is not available at a reasonable cost, or because it will not be revealed to the regulator by decision makers, or because there is no authority with the power to impose the required behavior. In such cases, Coase’s theorem does not apply because transaction costs are not negligible. Yet, stakeholders may be aware of the collective costs associated with the tragedy of the commons. They can try to improve the situation by signing contracts or treaties, sometimes involving cooperation. They will do so with due consideration for their position in the status quo as determined by their power.

SEE ALSO Coase Theorem; Externality; Overfishing; Property, Private; Rent

BIBLIOGRAPHY

Brander, Jim A., and M. Scott Taylor. 1998. The Simple Economics of Easter Island: A Ricardo-Malthus Model of Renewable Resource Use. American Economic Review 88 (1): 119–138.

Gordon, H. Scott. 1954. The Economic Theory of a Common-Property Resource: The Fishery. Journal of Political Economy 62: 124–142.

Hardin, Garrett. 1968. The Tragedy of the Commons. Science 162: 1243–1248.

Ostrom, Elinor. 1990. Governing the Commons: The Evolution of Institutions for Collective Action. Cambridge, U.K.: Cambridge University Press.

Pierre Lasserre

Tragedy of the Commons

The term tragedy of the commons was coined by Garrett Hardin who hypothesized in 1968 that, as the size of the human population increased, there would be mounting pressures on resources at the local and global levels, leading to overexploitation and ruin. Partly the tragedy would occur because some "commoners" (or users of common resources) would reap the full benefit of a particular course of action while incurring only a small cost, while others would have to share the cost but receive none of the benefits. The classic examples of such overexploitation are grazing, fishing, and logging, where grasslands, fish stocks, and trees have declined from overuse. Hardin suggested that governmental intervention and laws could become the major method of solving such overexploitation. More recently, the concept of the commons has been expanded to include air, water, the Internet, and medical care.

Much controversy has developed over whether commoners are caught in an inevitable cycle of overexploitation and destruction of resources, or whether the wise use and management of natural resources are possible. Although many examples of overexploitation exist, particularly in fisheries, Elinor Ostrom, Bonnie McCay, Joanna Burger, and others have argued that there are also examples of local groups effectively managing commonly held resources, and that such local control requires accepted rules, with appropriate sanctions and some governmental control to prevent exploitation by outside interests. That is, a fishing cooperative can succeed only if outside fishermen agree to adhere to existing rules or laws. In an age with increasing populations, understanding how different societies and groups have managed a common pool of resources allows us to apply successful methods in managing these resources.

see also Ehrlich, Paul; Limits to Growth, The; Malthus, Thomas Robert.

Bibliography

Burger, Joanna, and Gochfeld, Michael. (1998). "The Tragedy of the Commons—30 Years Later." Environment 41:4–13, 26–28.

Ostrom, Elinor; Burger, Joanna; Field, Christopher B.; Norgaard, Richard B.; and Policansky, David. (1999). "Revisiting the Commons: Local Lessons, Global Challenges." Science 284:278–282.

internet resource

Hardin, Garret. (1968). "The Tragedy of the Commons." Science 162:12–13. Also available from http://dieoff.org/page95.htm.

Joanna Burger