Tragedy of the commons

Cows on Selsley Common. The "tragedy of the commons" is one way of accounting for overexploitation.

The tragedy of the commons is an economics theory by Garrett Hardin, according to which individuals, acting independently and rationally according to each one's self-interest, behave contrary to the whole group's long-term best interests by depleting some common resource. The concept is often cited in connection with sustainable development, meshing economic growth and environmental protection, as well as in the debate over global warming. "Commons" can include the atmosphere, oceans, rivers, fish stocks, national parks, the office refrigerator, and any other shared resource. The tragedy of the commons has particular relevance in analyzing behavior in the fields of economics, evolutionary psychology, anthropology, game theory, politics, taxation, and sociology. Some also see the "tragedy" as an example of emergent behavior, the outcome of individual interactions in a complex system.

History

In 1833 William Forster Lloyd published a pamphlet on herders sharing a common parcel of land on which they are each entitled to let their cows graze. In English villages (as with mountain countries in Europe), shepherds had sometimes grazed their sheep in common areas, and sheep ate grass more severely than cows. Overgrazing could result because for each additional sheep, a herder could receive benefits, while the group shared damage to the commons. If all herders made this individually rational economic decision, the common could be depleted or even destroyed, to the detriment of all.

The same concept is sometimes called the "tragedy of the fishers", because fishing too many fish before or during breeding could cause stocks to plummet.

Garrett Hardin's article

In 1968, ecologist Garrett Hardin explored this social dilemma in "The Tragedy of the Commons", published in the journal, Science. Hardin discussed problems that cannot be solved by technical means, as distinct from those with solutions that require "a change only in the techniques of the natural sciences, demanding little or nothing in the way of change in human values or ideas of morality". Hardin focused on human population growth, the use of the Earth's natural resources, and the welfare state. If individuals relied on themselves and not on the relationship of society and man, Hardin argued that how many children a family would have would not be of public concern. Parents breeding excessively would leave fewer descendants because they would be unable to provide for each child adequately. Such negative feedback is found in the animal kingdom. Hardin says that if the children of improvident parents starved to death, if overbreeding was its own punishment, then there would be no public interest in controlling the breeding of families. Hardin blamed the welfare state for allowing the tragedy of the commons; where the state provides for children and supports overbreeding as a fundamental human right, Malthusian catastrophe is inevitable. Hardin lamented this interpretation of the Universal Declaration of Human Rights:

The Universal Declaration of Human Rights describes the family as the natural and fundamental unit of society. [Article 16] It follows that any choice and decision with regard to the size of the family must irrevocably rest with the family itself, and cannot be made by anyone else.

—U Thant, Statement on Population by UN Secretary-General

In addition, Hardin also pointed out the problem of individuals acting in rational self-interest by claiming that if all members in a group used common resources for their own gain and with no regard for others, all resources would still eventually be depleted. Overall, Hardin argues against relying on conscience as a means of policing commons, suggesting that this favors selfish individuals – often known as free riders – over those who are more altruistic. In the context of avoiding over-exploitation of common resources, Hardin concludes by restating Hegel's maxim (which was quoted by Engels), "freedom is the recognition of necessity." He suggests that "freedom" completes the tragedy of the commons. By recognizing resources as commons in the first place, and by recognizing that, as such, they require management, Hardin believes that humans "can preserve and nurture other and more precious freedoms."

Metaphoric meaning

Like William Lloyd and Thomas Malthus before him, Hardin was primarily interested in the problem of human population growth. In his essay, he also focused on the use of larger (though still limited) resources such as the Earth's atmosphere and oceans, as well as pointing out the "negative commons" of pollution (i.e., instead of dealing with the deliberate privatization of a positive resource, a "negative commons" deals with the deliberate commonization of a negative cost, pollution).

As a metaphor, the tragedy of the commons should not be taken too literally. The "tragedy" is not in the word's conventional or theatric sense, nor a condemnation of the processes that lead to it. Similarly, Hardin's use of "commons" has frequently been misunderstood, leading him to later remark that he should have titled his work "The Tragedy of the Unregulated Commons".

The metaphor illustrates the argument that free access and unrestricted demand for a finite resource ultimately reduces the resource through over-exploitation, temporarily or permanently. This occurs because the benefits of exploitation accrue to individuals or groups, each of whom is motivated to maximize use of the resource to the point in which they become reliant on it, while the costs of the exploitation are borne by all those to whom the resource is available (which may be a wider class of individuals than those who are exploiting it). This, in turn, causes demand for the resource to increase, which causes the problem to snowball until the resource collapses (even if it retains a capacity to recover). The rate at which depletion of the resource is realized depends primarily on three factors: the number of users wanting to consume the common in question, the consumptiveness of their uses, and the relative robustness of the common.

Criticisms

Nobel Prize-winning political scientist Elinor Ostrom and others revisited Hardin's work in 1999. They found the tragedy of the commons not as prevalent or as difficult to solve, since locals have often come up with solutions to the commons problem themselves; when the commons is taken over by non-locals, those solutions can no longer be used. Robert Axelrod contends that even self-interested individuals will often find ways to cooperate, because collective restraint serves both the collective and individual interests.

Hardin's work was also criticised as historically inaccurate in failing to account for the demographic transition, and for failing to distinguish between common property and open access resources. Carl Dahlman argues that commons were effectively managed to prevent overgrazing. Anthropologist G. N. Appell criticized those who cited Hardin to "impos[e] their own economic and environmental rationality on other social systems of which they have incomplete understanding and knowledge."

German historian Joachim Radkau thought Hardin advocates strict management of common goods via increased government involvement or international regulation bodies. An asserted impending "tragedy of the commons" is frequently warned of as a consequence for adopting policies which restrict private property and espouse expansion of public property.

Application

Modern commons

The tragedy of the commons can be considered in relation to environmental issues such as sustainability. The commons dilemma stands as a model for a great variety of resource problems in society today, such as water, forests, fish, and non-renewable energy sources such as oil and coal.

Situations exemplifying the "tragedy of the commons" include the overfishing and destruction of the Grand Banks, the destruction of salmon runs on rivers that have been dammed – most prominently in modern times on the Columbia River in the Northwest United States, and historically in North Atlantic rivers – the devastation of the sturgeon fishery – in modern Russia, but historically in the United States as well – and, in terms of water supply, the limited water available in arid regions (e.g., the area of the Aral Sea) and the Los Angeles water system supply, especially at Mono Lake and Owens Lake.

Other situations exemplifying the "tragedy of the commons" include congestion caused by driving cars. There are many negative externalities of driving; these include pollution, carbon emissions, and traffic accidents. For example, every time 'Person A' gets in a car, it becomes more likely that 'Person Z' – and millions of others – will suffer in each of those areas.

More general examples (some alluded to by Hardin) of potential and actual tragedies include:

Clearing rainforest for agriculture in southern Mexico.

• Planet Earth ecology
  • Uncontrolled human population growth leading to overpopulation.
  • Air, whether ambient air polluted by industrial emissions and cars among other sources of air pollution, or indoor air
  • Water – Water pollution, water crisis of over-extraction of groundwater and wasting water due to overirrigation
  • Forests – Frontier logging of old growth forest and slash and burn
  • Energy resources and climate – Environmental residue of mining and drilling, Burning of fossil fuels and consequential global warming
  • Animals – Habitat destruction and poaching leading to the Holocene mass extinction
  • Oceans – Overfishing
• Publicly shared resources
  • Spam email degrades the usefulness of the email system and increases the cost for all users of the Internet while providing a benefit to only a tiny number of individuals.
  • Vandalism and littering in public spaces such as parks, recreation areas, and public restrooms.
  • Knowledge commons encompass immaterial and collectively owned goods in the information age.
    • Including, for example, source code and software documentation in software projects that can get "polluted" with messy code or inaccurate information.

Modern solutions

Articulating solutions to the tragedy of the commons is one of the main problems of political philosophy. In absence of enlightened self-interest, some form of authority or federation is needed to solve the collective action problem. In a typical example, governmental regulations can limit the amount of a common good that is available for use by any individual. Permit systems for extractive economic activities including mining, fishing, hunting, livestock raising and timber extraction are examples of this approach. Similarly, limits to pollution are examples of governmental intervention on behalf of the commons. Alternatively, resource users themselves can cooperate to conserve the resource in the name of mutual benefit. Another solution for some resources is to convert common good into private property, giving the new owner an incentive to enforce its sustainability.

An opposing idea, used by the United Nations Moon Treaty, Outer Space Treaty and Law of the Sea Treaty as well as the UNESCO World Heritage Convention involves the international law principle that designates some areas or resources the Common Heritage of Mankind.

Libertarians and classical liberals cite the tragedy of the commons as an example of what happens when Lockean property rights to homestead resources are prohibited by a government. They argue that the solution to the tragedy of the commons is to allow individuals to take over the property rights of a resource, that is, privatizing it.

In Hardin's essay, he proposed that the solution to the problem of overpopulation must be based on "mutual coercion, mutually agreed upon" and result in "relinquishing the freedom to breed". Hardin discussed this topic further in a 1979 book, Managing the Commons, co-written with John A. Baden. He framed this prescription in terms of needing to restrict the "reproductive right" in order to safeguard all other rights. Only one large country has adopted this policy, the People's Republic of China.

Application to evolutionary biology

The tragedy of the commons is referred to in studies of evolutionary biology, social evolution, sociobiology and behavioral ecology. A tragedy of the commons is brought about by selfish individuals whose genes for selfish behaviour would therefore come to predominate, so the metaphor cannot explain how altruism arises. It is easy to see how cooperation can be evolved between related individuals through kin selection, but in order to understand cooperation between unrelated individuals mechanisms which confer direct benefits to the actor must be considered such as by-product benefits and reciprocal altruism.

A parallel was drawn recently between the tragedy of the commons and the competing behaviour of parasites that through acting selfishly eventually diminish or destroy their common host.

The idea has also been applied to areas such as the evolution of virulence or sexual conflict, where males may fatally harm females when competing for matings. It is also raised as a question in studies of social insects, where scientists wish to understand why insect workers do not undermine the "common good" by laying eggs of their own and causing a breakdown of the society.

The idea of evolutionary suicide, where adaptation at the level of the individual causes the whole species or population to be driven extinct, can be seen as an extreme form of an evolutionary tragedy of the commons.

The commons dilemma

The commons dilemma is a specific class of social dilemma in which people's short-term selfish interests are at odds with long-term group interests and the common good. In academia, a range of related terminology has also been used as shorthand for the theory or aspects of it, including resource dilemma, take-some dilemma, and common pool resource.

Commons dilemma researchers have studied conditions under which groups and communities are likely to under- or over-harvest common resources in both the laboratory and field. Research programs have concentrated on a number of motivational, strategic, and structural factors that might be conducive to management of commons.

In game theory, which constructs mathematical models for individuals' behavior in strategic situations, the corresponding "game", developed by the ecologist Garrett Hardin, is known as the Commonize Costs – Privatize Profits Game (CC–PP game).

Psychological factors

Kopelman, Weber, & Messick (2002), in a review of the experimental research on cooperation in commons dilemmas, identify nine classes of independent variables that influence cooperation in commons dilemmas: social motives, gender, payoff structure, uncertainty, power and status, group size, communication, causes, and frames. They organize these classes and distinguish between psychological individual differences (stable personality traits) and situational factors (the environment). Situational factors include both the task (social and decision structure) and the perception of the task.

Empirical findings support the theoretical argument that the cultural group is a critical factor that needs to be studied in the context of situational variables. Rather than behaving in line with economic incentives, people are likely to approach the decision to cooperate with an appropriateness framework. An expanded, four factor model of the Logic of Appropriateness, suggests that the cooperation is better explained by the question: "What does a person like me (identity) do (rules) in a situation like this (recognition) given this culture (group)?"

Strategic factors

Strategic factors also matter in commons dilemmas. One often-studied strategic factor is the order in which people take harvests from the resource. In simultaneous play, all people harvest at the same time, whereas in sequential play people harvest from the pool according to a predetermined sequence – first, second, third, etc. There is a clear order effect in the latter games: the harvests of those who come first – the leaders – are higher than the harvest of those coming later – the followers. The interpretation of this effect is that the first players feel entitled to take more. With sequential play, individuals adopt a first come-first served rule, whereas with simultaneous play people may adopt an equality rule. Another strategic factor is the ability to build up reputations. Research found that people take less from the common pool in public situations than in anonymous private situations. Moreover, those who harvest less gain greater prestige and influence within their group.

Structural factors

Much research has focused on when and why people would like to structurally rearrange the commons to prevent a tragedy. Hardin stated in his analysis of the tragedy of the commons that "Freedom in a commons brings ruin to all." One of the proposed solutions is to appoint a leader to regulate access to the common. Groups are more likely to endorse a leader when a common resource is being depleted and when managing a common resource is perceived as a difficult task. Groups prefer leaders who are elected, democratic, and prototypical of the group, and these leader types are more successful in enforcing cooperation. A general aversion to autocratic leadership exists, although it may be an effective solution, possibly because of the fear of power abuse and corruption.

The provision of rewards and punishments may also be effective in preserving common resources. Selective punishments for overuse can be effective in promoting domestic water and energy conservation – for example, through installing water and electricity meters in houses. Selective rewards work, provided that they are open to everyone. An experimental carpool lane in the Netherlands failed because car commuters did not feel they were able to organize a carpool. The rewards do not have to be tangible. In Canada, utilities considered putting "smiley faces" on electricity bills of customers below the average consumption of that customer`s neighborhood. Much field research on commons dilemmas has combined solutions obtained in experimental research. Elinor Ostrom, who was awarded 2009's Nobel Prize of Economics for her work on the issue, and her colleagues looked at how real-world communities manage communal resources, such as fisheries, land irrigation systems, and farmlands, and they identified a number of factors conducive to successful resource management. One factor is the resource itself; resources with definable boundaries (e.g., land) can be preserved much more easily. A second factor is resource dependence; there must be a perceptible threat of resource depletion, and it must be difficult to find substitutes. The third is the presence of a community; small and stable populations with a thick social network and social norms promoting conservation do better. A final condition is that there be appropriate community-based rules and procedures in place with built-in incentives for responsible use and punishments for overuse.

Related outcomes

Tragedy of the commons is one of four outcomes:

	Private ownership	Common ownership
Bad outcome/tragedy	Tragedy of the anticommons	Tragedy of the commons
Good outcome/cornucopia	Successful capitalism	Comedy of the commons

The prevalent outcome depends on the details of the situation. The opposite outcome to the tragedy is the "comedy of the commons" or "inverse commons", in which network effects or other causes enhance the value of rivalrous resources because of the lack of regulation or private ownership.

See also

• Diner's dilemma
• Fallacy of composition
• Free rider problem
• Game theory
• International Association for the Study of the Commons
• Nash equilibrium
• Social trap
• Somebody Else's Problem
• "The Market for Lemons"
• Tyranny of small decisions

Bibliography

• Angus, I. (2008). "The myth of the tragedy of the commons", Socialist Voice (August 24).
• Foddy, M., Smithson, M., Schneider, S., and Hogg, M. (1999). Resolving social dilemmas. Philadelphia, PA: Psychology Press.
• Messick, D. M.; Wilke, H. A. M.; Brewer, M. B.; Kramer, R. M.; Zemke, P. E.; Lui, L. (1983). "Individual adaptations and structural change as solutions to social dilemmas". Journal of Personality and Social Psychology 44 (294): 309. doi:10.1037/0022-3514.44.2.294. 
• Kopelman, S., Weber, M, and Messick, D. (2002). "Factors Influencing Cooperation in Commons Dilemmas: A Review of Experimental Psychological Research". In E. Ostrom et al., (Eds.) The Drama of the Commons. Washington DC: National Academy Press. Ch. 4., 113–156.
• Kopelman, S. (2009). "The effect of culture and power on cooperation in commons dilemmas: Implications for global resource management". Organization Behavior and Human Decision Processes, 108, 153–163. doi:10.1016/j.obhdp.2008.06.004.
• Locher, F. (2013). « Les pâturages de la Guerre froide : Garrett Hardin et la « Tragédie des communs » », Revue d'histoire moderne et contemporaine, vol. 2013, no 1, 2013, p. 7-36 (abstract)
• Ostrom, E. (1990). Governing the commons: The evolution of institutions for collective action. Cambridge: Cambridge University Press.
• Bryan Jones, B. J., and Howard Rachlin, H. R. (2006). "Social discounting". Psychological Science 17(4), 283–286. Retrieved from http://evolution.binghamton.edu/evos/wp-content/uploads/2009/08/Rachlin1.pdf.
• Rachlin, H. (1974). "Self-control". Behaviorism 2, 94–107.
• Rachlin, H., and Green, L. (1972). "Commitment, choice, and self-control". Journal of the Experimental Analysis of Behavior 17, 15–22.
• Van Vugt, M. (2001). "Community identification moderating the impact of financial incentives in a natural social dilemma". Personality and Social Psychology Bulletin 27 (11): 1440–1449. doi:10.1177/01461672012711005. 
• Van Vugt, M. (2009). "Triumph of the commons: Helping the world to share". New Scientist (2722): 40–43. 
• Van Vugt, M.; Van Lange, P. A. M.; Meertens, R. M.; Joireman, J. A. (1996). "Why structural solutions to social dilemmas might fail: A field experiment on the first carpool priority lane in Europe". Social Psychology Quarterly 59 (4): 364–374. doi:10.2307/2787077. 
• Weber, M., Kopelman, S., and Messick, D. (2004). "A conceptual review of decision making in social dilemmas: applying the logic of appropriateness". Personality and Social Psychology Review 8 (3), 281–307.

• Hardin, G. (1994). "The Tragedy of the Unmanaged Commons". Trends in Ecology & Evolution 9 (5): 199. doi:10.1016/0169-5347(94)90097-3. 
• Hardin, Garrett (2008). "Tragedy of the Commons". In David R. Henderson. Concise Encyclopedia of Economics (2nd ed.). Indianapolis: Library of Economics and Liberty. ISBN 978-0865976658. OCLC 237794267. 
• Ostrom, E. (1990). Governing the commons: The evolution of institutions for collective action. Cambridge: Cambridge University Press.
• Thinking Strategically: The Competitive Edge in Business, Politics, and Everyday Life by Avinash Dixit and Barry Nalebuff
• Kopelman, S., Weber, M, & Messick, D. (2002). Factors Influencing Cooperation in Commons Dilemmas: A Review of Experimental Psychological Research. In E. Ostrom et al., (Eds.) The Drama of the Commons. Washington DC: National Academy Press. Ch. 4., 113–156

External links

• Original article by Garrett Hardin from Science (journal)
• The Digital Library of the Commons
• The Myth of the Tragedy of the Commons by Ian Angus
• Global Tragedy of the Commons by John Hickman and Sarah Bartlett
• Tragedy of the Commons Explained with Smurfs by Ryan Somma