The Tragedy of the Commons and Sustainable Survival

An article on sustainability by Peter S. Cook

In 1968 the journal Science published an academic address by Garret Hardin called “The Tragedy of the Commons“, and it became a classic. It formed the basis for much thinking among social and environmental scientists, especially in relation to the over-exploitation of natural and economic resources, pollution of the environment, and over-population. Yet today, though many problems of sustainable survival are more urgent than in 1968, the operation of this Tragedy is seldom recognised in the lay media, and most people, and more importantly politicians, seem to have no idea what it means.

The “commons” is a metaphor for any collectively-owned and jointly managed asset. The Tragedy unfolds when single people or groups profit greatly by exploiting this resource, while the loss is shared between many others, so that to each of them the loss seems negligible.

Hardin illustrated the Tragedy with a parable. Imagine a pasture – traditionally known as a common or commons – on which herdsmen can graze their animals. Each grazes as many as he can, and this is sustainable so long as the number of men and animals is kept below the carrying capacity of the land, as by disease, poaching or war. But when these constraints are removed, numbers can increase and the logic of the commons generates tragedy unless steps are taken to prevent it.

So, if the land can carry one hundred sheep, ten herdsmen can have ten animals each, and this is sustainable. But now one of them decides to add one more animal, so making about ten percent more profit. The loss in feed for each individual sheep through grazing this one extra animal is only about 1%, and since this loss is shared between all ten herdsmen, it is so small that they don’t object. Being rational, our herdsman decides to add another animal … and another. The other herdsmen, seeing this, decide to do likewise and soon, through free access to the commons, it is overgrazed and ruined.

In an oft-quoted passage, Hardin said: “Therein is the tragedy. Each man is locked into a system that compels him to increase his herd without limit – in a world that is limited. Ruin is the destination to which all men rush, each pursuing his own best interest in a society that believes in the freedom of the commons. Freedom in a commons brings ruin to all”. Others have commented that this is not quite what happens. “Freedom in a commons only brings ruin to the commons”, while those who exploit it get rich and move on. The ruin for all comes later.

Hardin argued that in a democratic situation, restraint by “mutual coercion, mutually agreed upon” is the best way to prevent the Tragedy.

Let’s see now how the Tragedy can operate in areas such as ocean resources, over-population, environmental degradation, pollution, and economics.

Ocean resources

Hardin lamented the reluctance to acknowledge that the oceans of the world are subject to the Tragedy of the Commons. He said that, while professing to believe in the “freedom of the seas”, the maritime nations bring species after species of fishes and whales closer to extinction. Despite efforts in the intervening years, it will need much more international collaboration to stop the Tragedy running its course, as catches are depleted and breeding stocks of fish, turtles and other sea-foods are threatened with collapse. In traditional societies, mutually agreed coercion worked sustainably in well-defined areas, but on the high seas fishermen may see no point in throwing back undersized fish or breeding stock if other fishermen will come along and take them anyway.

Hardin said that, to make progress, we must exorcise the spirit of Adam Smith, with his doctrine that an individual who “intends only his own gain” is, as it were, “led by an invisible hand to promote … the public interest”. The Tragedy of the Commons exposes the fallacy that decisions reached individually will also be the best decisions for an entire society – an idea underpinning much economic argument.


“Exploring new ethics for survival” was an important theme in Hardin’s writing. His original essay was subtitled “The population problem has no technical solution; it requires a fundamental extension in morality”. Applying this to the population explosion, he concluded that if Adam Smith’s assumption were correct, it would justify the continuance of laissez-faire in reproduction, and men and women would naturally control their individual fertility to produce the optimum population. But he said that if Adam Smith’s assumption is not correct, then we need to examine our individual freedoms to see which ones are defensible. As Jarred Diamond has shown, a civilisation may cause much environmental degradation with destruction of its resource base and extinction of species before its own population collapse occurs. We are now causing the greatest species extinction since the demise of the dinosaurs.

With respect to the freedom to breed, Hardin argued that The Universal Declaration of Human Rights is fatally flawed in declaring 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”. He said that painful though it may be, “If we love the truth we must openly deny the validity of this Declaration, even though it is promoted by the United Nations”. He argued that to couple the concept of freedom to breed with the belief that everyone born has an equal right to the commons is to lock the world into a tragic course of action, and we cannot control the breeding of humans in the long run by appeals to conscience. As human populations increase, individuals locked into the logic of the commons through unrestricted freedom to breed, are free only to bring on universal ruin, unless they accept the necessity of mutual coercion, mutually agreed upon, and by this they become free to pursue other goals. The only way we can preserve and nurture other and more precious freedoms is by relinquishing freedom to breed. Only so can we put an end to this aspect of the Tragedy of the Commons. Today, some religious authorities still denounce most methods of birth control as inherently evil. But if this dogma leads to human disasters and planetary degradation, wherein is the greater evil?

Environmental degradation – loss of biodiversity

The Tragedy of the Commons, in various guises, underlies much of the degradation of our forests, soils, rivers, wetlands, coral reefs and oceans, with massive losses of biodiversity of native flora and fauna. In each particular instance, the gain to the exploiter is much greater than any individual’s share of the loss. The problems of sharing but not polluting a common resource is urgent in our mis-use of rivers, estuaries and artesian water reserves.

Many traditional societies regulated their commons sustainably, but when this failed privatization of the Commons was sometimes a solution, assuming that an individual owner would take the long view and use it sustainably. Yet privatization to corporate bodies which aim to maximise short-term profits makes the problem worse, and legal entities such as companies do not feel the loss at all. Only when disaster looms will Governments act, but State ownership, too, can fail when rights are conferred for private exploitation.


The Tragedy applies in a reverse way with global pollution. Here it is not a matter of taking something out of the commons, but of putting pollution in. Sewage, chemical, and radioactive wastes are put into soil or water, and noxious fumes, or gases such as carbon dioxide, are dumped into the atmosphere. Again, the so-called “rational man” sees that his share in the costs of the pollution he creates is much less than it would cost him to rectify the problem. Since this is true for everyone, we are locked into a system of “fouling our own nest” so long as we behave only as independent, rational free-enterprisers.

The air and seas around us cannot be fenced off, so the Tragedy of the Commons as a sink or cesspool has been approached by other means – like laws or taxes which make it cheaper for the polluter to treat his pollutants than to discharge them untreated. The “greenhouse effect” and the ozone hole are global Tragedies of the Commons. Like so many other problems, pollution is a consequence of large population. It didn’t matter how a few isolated people disposed of their waste.

In December 1995 I spoke on this program about some impacts of wear-out and throw-away products. In January 1999 a report in the Sydney Morning Herald said the disposable car is now a reality. After the warranty expires in some small imported cars, it costs more to replace parts such as a gearbox than the whole car will be worth when it’s repaired, so it is cheaper for the owner to throw it away. But there was no acknowledgment of the planetary cost of everyone doing this, and no outrage or protest followed. That shiploads of wear-out products are silently polluting and degrading our planetary environment is a major Tragedy of our Commons.


The principle of the Tragedy was originally described in 1833 by a mathematician, William Lloyd. Applying it to the jobs market, he saw the pool of available work and the money available from it as a commons. To get it, men who were desperate to feed their families would each bid down the price of labour below a living wage rather than starve, and in the process reduce the total pool of wages available. Perhaps this is now happening internationally in some poorer countries. Within Western societies, trade unions historically emerged to counter this threat, but unfortunately they can generate their own Tragedy. In some ways an economy is like a commons. Unless a wage increase is matched by increased productivity, a wage increase for one union corresponds to a herdsman having more sheep. The gain to each member of that union is much greater than any single person’s loss as their share of the cost. The wage increase has a small inflationary effect, which is spread through the whole community. If other groups strike to keep up with the “pace-setters”, the Tragedy of the Commons can operate, as we saw with inflation in the 1970’s. In the 1980’s the Australian Government’s “Accord” with the trade unions to achieve wage restraint was an example of controlling the Tragedy of inflation by “mutual coercion, mutually agreed upon”.

Since Hardin put the Tragedy on the agenda in 1968, various social and political movements have tried to exert pressure to maintain the Commons. But our planet has three times as many people as when I was a boy and much of our globe is still a Commons exposed to this Tragedy. Many animals which were then fairly numerous, such as tigers and some great apes, are now in danger of extinction. Once you grasp the principles I think you may find that recognising this process sheds light on many current affairs. To safeguard the health of our earth, and indeed the future of our species, it is essential that we recognise far more widely the Tragedies which are threatening our Commons.


  1. 1. Hardin, G. (1968). The tragedy of the commons. Science,162: 1243-1248. (The full text can readily be found on the internet.)
  2. 2. Hardin, G.(1972). Exploring new ethics for survival: the voyage of the spaceship Beagle. Penguin, Baltimore. (First published by Viking Press 1968.)
  3. 3. Lloyd, W.F., (1833) Two lectures on the checks to population. Oxford University Press, Oxford. Reprinted in part in Hardin G. (1964) Population, evolution, and birth control. Freeman, San Francisco.