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Tragedy of the commons

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The tragedy of the commons is a phrase used to refer to a class of phenomena that involve a conflict for resources between individual interests and the common good. The term derives originally from a parable published by William Forster Lloyd who was Drummond Professor at Oxford and a Fellow of the Royal Society, in his 1833 book on population. It was then popularized and extended by Garrett Hardin in his 1968 Science essay "The Tragedy of the Commons".

Introduction

The parable demonstrates how unrestricted access to a resource such as a pasture ultimately dooms the resource because of over-exploitation. This occurs because the benefits of exploitation accrue to individuals, while the costs of exploitation are distributed between all those exploiting the resource.

Like William Lloyd, Hardin was primarily interested in population and especially the problem of human population growth (similarly also to Thomas Malthus). However, he also focused more generally on the use of resources such as the atmosphere and oceans, as well as pointing out the 'negative commons' of pollution.

Similarly to the phrase "Survival of the fittest", coined by Herbert Spencer and also widely misinterpreted, the "Tragedy of the commons" is a metaphor chosen for the way it "trips off the tongue", and should not be taken too literally as defining the concept. Hardin himself said that he used the word 'tragedy' in the sense that the philosopher Alfred Whitehead used it: "the remorseless working of things". The phrase is shorthand for a phenomenon, not an accurate description of it. Furthermore, 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.

The 'Tragedy of the Commons' has particular relevance in explaining behaviour in the fields of evolutionary psychology and sociology. More generally, it can be seen as an example of game theory, with the trading of costs and benefits between "players". Some also see it as an example of emergent behaviour, with the 'tragedy' the outcome of individual interactions in a complex system.

The Essay

At the beginning of his essay, Hardin draws attention to problems that cannot be solved by technical means (i.e. as opposed to those problems 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 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 maximise population, one needs to minimise 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 maximise 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 components is unequal: the individual herder gains all of the advantage, but the disadvantage is shared between all herders using the pasture. Consequently, for an individual herder weighing up these utilities, the rational course of action is to add an extra animal. And another, and another. However, since all herders reach the same 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 an individual than the distributed cost is. 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). As such, it illustrates how simplistic "invisible hand" (laissez-faire) approaches to resource problems need not provide the expected optimal solution. In Hardin's hypothetical commons, the action of self-interested individuals cannot promote the public good.

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. 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 more far-sighted.

In the context of avoiding over-exploitation of commons, Hardin concludes by restating Hegel's maxim, "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".

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 above).

More significantly, controversy has been fuelled 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 and privatised. Ostensibly this serves to "protect" such resources, but it ignores the pre-existing management, often unfairly appropriating resources and alienating indigenous (and frequently poor) populations. 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.

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.

Under many modern understandings of property (e.g. that of the USA), these bundles of rights would not have been "property" either, since they could not be traded or otherwise disposed of. However, these commoner's rights applied in a medieval culture which did recognise 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. (the form "commons" is plural, and refers to the whole group of commons subject to these effects).

Historically, most English commons were reserved for their own commoners, whose use was restricted in various ways according to local custom. In reponse 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. While historians continue to debate the significance and impact of enclosure on small landholders and labouring people in England, they agree that there is no evidence that commonland use was itself unsustainable.

Possible solutions to the 'tragedy'

Articulating solutions to the tragedy of the commons is one of the main problems of political philosophy. Many such solutions involve enforcement of conservation measures by an authority, which may be an outside agency or selected by the resource users themselves, who agree to cooperate to conserve the resource. Another frequently-proposed solution is to convert each common into private property, giving the owner of each an incentive to enforce its sustainability. Effectively, this is what took place in the English "Enclosure of the Commons"; this case highlights the effects of hidden wealth transfer in privatization, if no or inadequate matching compensation occurs. Moreover, as demonstrated by recent conflicts over logging, snow cover and water resources in the Upper Rio Grande watershed, there are questions about whether individual ownership does provide an incentive to enforce its sustainability, particularly if the property is not looked on as a long term investment. 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.

A popular solution to the problem is also the "Coasian" one, where the individuals using the commons make payments to one another in exchange for not overusing 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[1]. 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 Peoples Republic of China. Given this particular country's abysmal record regarding civil rights and liberties, it is quite ironic that it is the sole major country to have adopted Hardin's prescription. 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. Indeed, governments of some developed countries (e.g. Japan) are now concerned with raising rather than lowering the birthrate.

Games Theory analysis

The tragedy of the commons can be seen as a collective prisoner's dilemma. Individuals within a group have two options: cooperate with the group or defect from the group. Cooperation happens when individuals agree to protect a common resource to avoid the tragedy. By cooperating, every individual agrees not to seek more than his share. Defection happens when an individual decides to use more than his share of a public resource.

Game theory shows that individuals benefit from defecting in the prisoner's dilemma (even though both would be better off if both cooperated than if both defected), unless there is some individual cost to defecting. In the iterated prisoner's dilemma, retaliation for past defection can make cooperation the best choice even for a selfish individual. Similarly, far-sighted groups that impose some sort of sanction on members that over-exploit a resouce can make over-exploitation unprofitable. This is trickier for larger groups.

Application to Evolutionary Psychology

The "tragedy of the commons" features highly in the field of Evolutionary psychology, along with the closely linked "Prisoner's dilemma". Until quite recently, it was widely held that altruism could not have evolved because the 'tragedy of the commons' would always favour sefish individuals; whose genes for selfish behavour would therefore come to predominate. Understanding this led many to study and to model possible mechanisms that might give rise to 'Reciprocal altruism', leading to ideas like the 'Tit for tat' rule. This freed evolutionary theory from the limitations imposed by the concept of 'Inclusive fitness', another explanation for altruism, which proposed that we only help others to the extent that by doing so we assist the survival of genes that they share with us.

Modern commons

Modern commons (some alluded to by Hardin) include :

See also