A term used to describe the process whereby limited resources, regarded as common property or public goods under common ownership, leads to exploitation and the degradation of the common good.
Definition: A process whereby limited resources, regarded as common property to all humans, falls under a common ownership that leads to over-exploitation and ruin.
Reference: Garrett Hardin, 1974 paper - well-meaning but misguided policies that grant everyone access without sufficient property rights could create a tragedy of the commons.
Reference: Garrett Hardin: 1968 - "Ruin is the destination toward 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."
Insight: When the Earth's resources - air, water, fish, are treated as commons, there is no proper stewardship. and ruin will follow.
Example: In the developed world, we can largely live happy and healthy lives by consuming less. But the tendency is to consume more, and this may lead to a situation where resources are depleted.
Insight: Humans are not good at taking personal action to solve collective problems.
Insight: Societal change for good can happen when self-interest aligns with common good.
Example: Farmers and fishermen - as a collective both prefer to avoid overgrazing or overfishing, but individually each farmer or fisherman would personally gain from their own over-farming or overfishing, if others don't.
Insight: The downfall of socialism is the individual interests do not work well under a collective (or commons) system; but a system of purely private property does also not work well.
Reference: Elinor Ostrom - there exists a particular community size below which people protect the commons, but these groups cannot be too large otherwise there less incentive for the groups to protect the commons.
Reference: Garrett Hardin, biologist - the Tragedy of the Commons does not distinguish between "open-access free-for-alls" and "communally owned property". Free-for-alls are subject to cheaters, whereas communally owned properties can be carefully regulated.
Insight: Large, "nationalised" or government managed properties face the problem of too few resources to manage the property, people having incentives to cheat, and it becoming a free-for-all on a large scale.
Reference: Garrett Hardin 1968 paper - cows and common pasture - each farmer seeks to add more animals to their herd and has incentive to do so to maximise gains.
Insight: Adding more resources to a common good has positive utility for the individual (the proceeds of farming or fishing), but negative utility for the entire resource as a whole. The negative utility is spread among all individuals such that the individual feels it less.
Insight: "Ruin is the destination toward 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."
Definition: Occurs when people do not consider the cost of their actions to others when using public goods, and therefore public resources are overused.
Insight: A reason for property rights is to prevent overuse.
Insight: Information or intellectual property is not destroyed or diminished through consumption and therefore cannot be overused. The use of ideas by one person does not make anyone else less able to use them.
Reference: Garrett Hardin - described what happens on common land - example of sheep grazing causing a destruction of the land by overuse.
Reference: John Sulston in a report argues humanity to think beyond competition: '"So long as an excess of competition between nations continues," the report concludes, "the future of humanity is in doubt."'
Insight: Hardin's 1968 paper was controversial as it had no technical solution to the problem of resource allocation, only a "fundamental extension of morality".
Insight: Taken together, game theory and The Tragedy of the Commons illustrates the destructiveness of competitive self interest.
Definition: Occurs when people abuse a resource because they do not own it.
Reference: Adam Smith - recognised that there were circumstances when the invisible hand would not work, including the Tragedy of the Commons.
Insight: Poor or insufficient property rights can damage an economy - ownership encourages people to invest in and safeguard the value of their property.
Insight: Where there is a limited resource, those exploiting it will do so to the detriment of their neighbours.
Example: Carbon emissions and the environment.
Insight: People benefit from other's sacrifices and suffer from their own - so everyone has an incentive to free ride, and everyone suffers.
Insight: A solution is an authority that can punish free riders, however government with that power is unlikely to restrict power to maximising the common good.
Insight: Carbon pricing/taxes combine government and market intervention.
Reference: Garrett Hardin - the liberal view that everyone should have fair and equal share of the worlds resources would lead to ruin.
Example: Cow grazing on a commons will eventually lead farmers to add more cattle until the commons is ruined from overgrazing.
Insight: When the Earth's resources - air, water, fish, are treated as commons, there is no proper stewardship. and ruin will follow.
Reference: Joshua Greene, book Moral Tribes - common grazing field with sheep, there is no incentive to cooperate and everyone free rides.
Insight: When framed in the context of morality, preventing the Tragedy of the Commons requires people in large groups not to be selfish, but often there are opposing groups of people.
Example: Overfishing the ocean commons.
Reference: Garrett Hardin 1968 article: common land and grazing cows - demonstrates the tragic economic logic of the commons - each individual farmer that has access to the commons has an incentive to add more cows until the common cannot support any more and the common deteriorates.
Insight: Rational behaviour can have irrational outcomes.
Reference: Garrett Hardin, American biologist, (1968) "tragedy of the commons" article: argued that there is a tension between the private good and the collective whole - common land would lead to environmental devastation.
Reference: Garrett Hardin, biologist - the example of overgrazing common land in 15th and 16th century England.
Reference: Elinor Ostrom - studies to resolve tragedy of the commons, to preserve common property resources.
Example: The environment; dairy farmers, and fishermen - each individual farmer or fisherman pays a fraction of the cost of additional farming or fishing resources on the common good, whilst gaining the benefits.
Insight: Tragedy of the Commons occurs when individuals are unlikely to pay for the individual harm or impacts their choices have on common goods.
Insight: We often need to take collective action to safeguard or restore a common resource. However the larger the number of individuals involved, the more incentive for each individual to cheat the system and reap the benefits without contributing.
Insight: A a large enough number of people become free riders, there won't be a resource to free ride on.
Reference: Garrett Hardin - argues that greed and self-interest are powerful motivations with the example of shared pasture commons and overgrazing.
Insight: Throughout history people have been able to work together [in smaller groups] to limit damage to common goods.
Key Insights & Principles
Sustainability
Humans are poor at taking individual actions for the common good.
Competitive self interest can be destructive.
When self-interest aligns with common good, positive societal change is possible.
Communally owned and managed properties that are effectively regulated are more optimal than open-access free-for-alls.
Property rights can prevent overuse of resources.
Intellectual property, or information, is not diminished through 'overconsumption' and cannot be overused, and therefore not subject to tragedy of the commons. The use of ideas does not make anyone else less able to use them.
Safeguarding common resources requires collective action, but as the number of individuals grows, the incentive to free-ride becomes higher.
Smaller groups can be effective in managing common groups - as free riding becomes more visible.
