Tragedy of the commons

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The tragedy of the commons is a type of social trap, often economic, that involves a conflict over finite resources between individual interests and the common good. It states that free access and unrestricted demand for a finite resource ultimately structurally dooms the resource through over-exploitation. The term derives originally from a comparison noticed by William Forster Lloyd with medieval village land holding in his 1833 book on population.^[1] It was then popularized and extended by Garrett Hardin in his 1968 Science essay "The Tragedy of the Commons."^[2] However, the theory itself is as old as Thucydides^[3] and Aristotle.^[4]

Such a notion is not merely an abstraction, but its consequences have manifested literally, in such common grounds as Boston Common, where overgrazing required the Common no longer be used as public grazing ground.^[5]

Contents 1 Garrett Hardin's essay 2 Meaning 3 Controversy 4 Historical commons 5 Modern commons 6 Modern solutions 7 Application to evolutionary biology 8 Application to social evolution 9 See also 10 Notes 11 External links and references 12 Further reading

[edit] Garrett Hardin's essay

At the beginning of his essay, Hardin draws attention to problems that cannot be solved by technical means (i.e., 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 contends that this class of problems includes many of those raised by human population growth and the use of the Earth's natural resources.

To make the case for "no technical solutions", Hardin notes the limits placed on the availability of energy (and material resources) on Earth, and also the consequences of these limits for "quality of life". To maximize population, one needs to minimize resources spent on anything other than simple survival, and vice versa. Consequently, he concludes that there is no foreseeable technical solution to increasing both human populations and their standard of living on a finite planet.

From this point, Hardin switches to non-technical or resource management solutions to population and resource problems. As a means of illustrating these, he introduces a hypothetical example of a pasture shared by local herders. The herders are assumed to wish to maximize their yield, and so will increase their herd size whenever possible. The utility of each additional animal has both a positive and negative component:

• Positive: the herder receives all of the proceeds from each additional animal.
• Negative: the pasture is slightly degraded by each additional animal.

Crucially, the division of these costs and benefits is unequal: the individual herder gains all of the advantage, but the disadvantage is shared among all herders using the pasture. Consequently, for an individual herder weighing these, the rational course of action is to add an extra animal. And another, and another. However, since all herders reach the same rational conclusion, overgrazing and degradation of the pasture is its long-term fate. Nonetheless, the rational response for an individual remains the same at every stage, since the gain is always greater to each herder than the individual share of the distributed cost. The overgrazing cost here is an example of an externality.

Because this sequence of events follows predictably from the behaviour of the individuals concerned, Hardin describes it as a tragedy: "the remorseless working of things" (in the sense described by the philosopher Alfred Whitehead).

In the course of his essay, Hardin develops the theme, drawing in examples of latter day "commons", such as the atmosphere, oceans, rivers, fish stocks, National Parks, advertising, and even parking meters. The example of fish stocks had led some to call this the "tragedy of the fishers".^[6] A major theme running throughout the essay is the growth of human populations, with the Earth's resources being a general commons (given that it concerns the addition of extra "animals", it is the closest to his original analogy).

The essay also addresses potential management solutions to commons problems including: privatization; polluter pays; regulation. Keeping with his original pasture analogy, Hardin categorises these as effectively the "enclosure" of commons, and notes a historical progression from the use of all resources as commons (unregulated access to all) to systems in which commons are "enclosed" and subject to differing methods of regulated use (access prohibited or controlled). Hardin argues against the reliance on conscience as a means of policing commons, suggesting that this favours selfish individuals over those with greater foresight.

In the context of avoiding over-exploitation of common resources, Hardin concludes by restating Hegel's maxim (which was actually written by Engels), "Freedom is the recognition of necessity." He suggests that "freedom", if interpreted narrowly as simply the freedom to do as one pleases, completes the tragedy of the commons. By recognising resources as commons in the first place, and by recognising that, as such, they require management, Hardin believes that "we can preserve and nurture other and more precious freedoms."

Aside from its subject matter (resource use), the essay is notable (at least in modern scientific circles) for explicitly dealing with issues of morality, and doing so in one of the scientific community's premier journals, Science. Indeed, the subtitle for the essay is "The population problem has no technical solution; it requires a fundamental extension in morality."

[edit] Meaning

The metaphor illustrates how free access and unrestricted demand for a finite resource ultimately structurally dooms the resource through over-exploitation. 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 distributed among all those to whom the resource is available (which may be a wider class of individuals than that which is exploiting it). This, in turn, causes demand for the resource to increase, which causes the problem to snowball to the point in which the resource is exhausted.

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

As a metaphor, the tragedy of the commons should not be taken too literally. The phrase is shorthand for a structural relationship and the consequences of that relationship, not a precise description of it. The "tragedy" should not be seen as tragic in the conventional sense, nor must it be taken as condemnation of the processes that are ascribed to it. Similarly, Hardin's use of "commons" has frequently been misunderstood, leading Hardin to later remark that he should have titled his work "The Tragedy of the Unregulated Commons".^[7]

The tragedy of the commons has particular relevance in analyzing behaviour in the fields of economics, evolutionary psychology, game theory, politics, taxation, and sociology. Some also see it as an example of emergent behaviour, with the "tragedy" the outcome of individual interactions in a complex system.

[edit] Controversy

Even today Hardin's essay "The Tragedy of the Commons" is a source of controversy. Some of this stems from disagreement about whether individuals will always behave in the selfish fashion posited by Hardin (see discussion below).

More significantly, controversy has been fueled by the "application" of Hardin's ideas to real situations. In particular, some authorities have read Hardin's work as specifically advocating the privatisation of commonly owned resources. Consequently, resources that have traditionally been managed communally by local organisations have been enclosed or privatised. Ostensibly this serves to "protect" such resources, but it ignores the pre-existing management, often appropriating resources and alienating indigenous (and frequently poor) populations. In effect, private or state use repeatedly resulted in worse outcomes than compared to the previous commons management.^[8] As Hardin's essay focuses on resources that are fundamentally unmanaged, rather than communally managed, this application of his ideas is misplaced. Ironically, given his original hypothetical example, this misunderstanding of Hardin's ideas is often applied to grazing lands.

More generally, Hardin made it very clear that usage of public property could be controlled in a number of different ways to stop or limit over-usage. As has been pointed out by Natalie Wanis, Hardin's advocacy of clearly defined property rights has frequently been misread as an argument for privatization, or private property, per se. The opposite situation to a tragedy of the commons is sometimes referred to as a tragedy of the anticommons: a situation where rational individuals (acting separately) collectively waste a given resource by under-utilizing it.

[edit] Historical commons

Hardin's essay introduces a hypothetical pasture as an analogy for "commons" in general. In this analogy, herders using the pasture do so on an individualistic basis, with no community management or oversight. However, actual historical commons were not public land and most were not open to the access of all — the public at large had very limited rights (e.g., passing drovers could lease grazing for "thistle rent"). Only those locals who were "commoners" had access to a bundle of rights; each commoner then had an interest in his own rights, but the common itself was not property.

These bundles of rights could not be traded or otherwise disposed of, but they applied in a medieval culture that recognized inalienable property (e.g., entailed inheritances), so under this system the bundles of rights were considered property. In a traditional English village these rights provided commoners with rights of grazing, gathering fuel wood non-destructively "by hook or by crook", etc., from anywhere on the common. (The form "commons" is plural, and refers to the whole group of individual pieces of common land subject to these effects.)

Historically, most English commons were reserved for their own commoners (meaning members of that parish), whose use was restricted in various ways according to local custom. In response to overgrazing, for example, a common would be "stinted", that is, a limit would be put on the number of animals each commoner was allowed to graze. This stint might be related to the ownership of a commonable cottage, or to the amount of land owned in the open fields. These regulations were responsive to demographic and economic pressure; rather than let the commons be degraded, access was usually restricted even further. By the time of parliamentary enclosure, in many manors in southern England few labourers and poorer people held common grazing rights; enclosure, however, did have an impact on smaller landholders who supported their farming through use of common grazing and other resources.

[edit] Modern commons

Situations exemplifying the "tragedy of the commons" include the overfishing and destruction of the Grand Banks, the destruction of salmon runs on rivers which have been dammed (most prominently in modern times on the Columbia River in the NW US, but historically in N Atlantic rivers generally), the devastation of the sturgeon fishery (in modern times especially in Russia, but in historical times in the US 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.

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

• Planet Earth
  • Uncontrolled human population growth leading to overpopulation.^[2]
  • Water - Water pollution, Water crisis of over-extraction of groundwater and wasting water due to overirrigation^[9]
  • Forests - Frontier logging of old growth forest and slash and burn^[10]
  • Energy resources and climate - Burning of fossil fuels and consequential global warming
  • Animals - Habitat destruction and poaching leading to the Holocene mass extinction^[11]
  • Oceans - Overfishing^[12]

• Public resources
  • Radio frequencies - Unlicensed frequencies used for wireless communications especially 802.11 a/b/g, detailed under Part 15 (FCC rules) are vulnerable to the overuse of high power transmitters, especially overdriven transmitters with dirty signal profiles, and especially when combined with omnidirectional antennas

[edit] Modern solutions

Articulating solutions to the tragedy of the commons is one of the main problems of political philosophy. The most common solution is regulation by an authority. Frequently, such regulation is in the form of governmental regulations limiting the amount of a common good 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 certain resources is to convert common good into private property, giving the new owner an incentive to enforce its sustainability. Effectively, this is what took place in the English "Enclosure of the Commons". Increasingly, many agrarian studies scholars advocate studying traditional commons management systems, to understand how common resources can be protected without alienating those whose livelihoods depend upon them.

Libertarians and classical liberals often cite the tragedy of the commons as a classic example of what happens when Lockean property rights to homestead resources are prohibited by a government.^[13][14][15] These people 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.^[16] In 1940 Ludwig von Mises wrote concerning the problem:

If land is not owned by anybody, although legal formalism may call it public property, it is used without any regard to the disadvantages resulting. Those who are in a position to appropriate to themselves the returns — lumber and game of the forests, fish of the water areas, and mineral deposits of the subsoil — do not bother about the later effects of their mode of exploitation. For them, erosion of the soil, depletion of the exhaustible resources and other impairments of the future utilization are external costs not entering into their calculation of input and output. They cut down trees without any regard for fresh shoots or reforestation. In hunting and fishing, they do not shrink from methods preventing the repopulation of the hunting and fishing grounds.^[17]

Critics of this solution have pointed out that many commons, such as the ozone layer or global fish populations, would be extremely difficult or impossible to privatize.

Psychologist Dennis Fox used a number, what is now termed "Dunbar's number", to take a new look at the tragedy of the commons. In a 1985 paper titled "Psychology, Ideology, Utopia, & the Commons", he stated "Edney (1980, 1981a) also argued that long-term solutions will require, among a number of other approaches, breaking down the commons into smaller segments. He reviewed experimental data showing that cooperative behavior is indeed more common in smaller groups. After estimating that "the upper limit for a simple, self-contained, sustaining, well-functioning commons may be as low as 150 people" (1981a, p. 27).

The Coast Salish managed their natural resources in a place-based system where families were responsible for looking after a place and its resources.^[18] Access to food was the major source of wealth and the empowerment of generosity was highly valued so it made sense for them to take care of the resources.

A popular solution to the problem is also the "Coasian" one, where the people using the commons support one another so not to destroy the resource.

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.^[19] 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. In the essay, Hardin had rejected education as an effective means of stemming population growth. Since that time, it has been shown that increased educational and economic opportunities for women correlates well with reduced birthrates in most countries, as does economic growth in general.

[edit] Application to evolutionary biology

A parallel was drawn recently ^[20] between the tragedy of the commons and the competing behaviour of parasites that through acting selfishly eventually diminish or destroy their common host.

[edit] Application to social evolution

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. This question is addressed instead by models of possible mechanisms that can give rise to "reciprocal altruism", leading to ideas like the "tit for tat" rule (reciprocation). These models freed evolutionary theory from the limitations imposed by the concept of "inclusive fitness", a previous explanation for altruism, which proposed that organisms help others only to the extent that by doing so they increase the probability of passing shared genes to the next generation.

The idea has been applied to other areas of sociobiology and behavioral ecology, such as in the evolution of virulence or sexual conflict, where males may fatally harm females when competing for matings.^[21] 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.

[edit] See also

Common-pool resource Demographic transition Elinor Ostrom Enclosure of the commons Free-market environmentalism Free rider problem Green syndicalism Lifeboat ethics Polder model

Political economy Population control Property rights (economics) Property rights (Law) Ratchet effect Thomas Malthus Malthusian catastrophe Tragedy of the anticommons

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[edit] Notes

[edit] External links and references

• Original article by Garrett Hardin from the Science Magazine website
• What about the "Tragedy of the Commons"? Surely communal ownership will lead to overuse and environmental destruction? -- Libertarian Socialist critique of the "Tragedy of the Commons"
• Edney, J. J. (1981a). Paradoxes on the commons: Scarcity and the problem of equality. Journal of Community Psychology, 9, 3-34.
• Ecotourism literature review
• The Tragedy of the Commons (Uncluttered version)
• The Garrett Hardin Society
• Traditional Resource Management of the Coast Salish Avoided the Tragedy of the CommonsPDF (82.7 KiB)
• "Resolving the Tragedy of the Commons by Creating Private Property Rights in Wildlife", Robert J. Smith, Cato Journal, Vol. 1, No. 2 (Fall 1981), pp. 439-468.
• "Law, Property Rights, and Air Pollution",PDF (1.75 MiB) Murray N. Rothbard, Cato Journal, Vol. 2, No. 1 (Spring 1982), pp. 55-100.
• "Free-Market Environmentalism Reading List", The Commons Blog.
• The Tragedy of the Digital CommonsPDF (61.5 KiB) by Gian Maria Greco and Luciano Floridi
• "Global Tragedy of the Commons at COP 6" by John Hickman and Sarah Bartlett
• "The Tragedy of the Advertising Commons" by Matthew Syrett
• Slate: "Awareness bracelets and the tragedy of the commons" by Timothy Noah
• The Nuts Game: A Concise Commons Dilemma Analog
• Property Rights & the Tragedy of the Commons - Fishing GamePDF (124 KiB) Instruction on performing a classroom experiment to illustrate the behavior
• The Management of Common Land in North West Europe edited by Martina de Moor, Leigh Shaw-Taylor, and Paul Warde
• Psychology, Ideology, Utopia the Commons Article by Dennis Fox a critical psychologist
• A video of a lecture by UCLA Sociology Professor Peter Kollock (smaller version) in January 2005 on social dilemmas, the Tragedy of the Commons, and public goods.
• Sandvine, Network Neutrality: A Broadband Wild West?
• Sexual Conflict as a Tragedy of the CommonsPDF (66.5 KiB) by Daniel J. Rankin and Hanna Kokko
• Paper on The Tragedy of the Commons in Evolutionary Biology

[edit] Further reading

• Hardin, G. (May 1998). "Extensions of "The Tragedy of the Commons"". Science 280 (5364): 682-683. doi:10.1126/science.280.5364.682. 
• Hardin, G. (1994). "The Tragedy of the Unmanaged Commons". Trends in Ecology & Evolution 9: 199.