Tragedy of the Commons

What Tragedy of the Commons means

The tragedy of the commons is what happens when a resource is shared and open, and each user, acting sensibly for themselves, takes a little more than the resource can bear, until it is gone for everyone. That is the definition. Owning it changes who we blame and what we try. We stop looking for the greedy one, because the well-meaning user faces the same sums as the careless one. We stop believing a plea to "be considerate" will hold, because whoever holds back watches the others take their share. We start asking what the others can see and what they have agreed to. Before, the empty fishery looked like a moral failure. After, it looks like a missing rule, and rules can be written.

Not to be confused with

The tragedy of the commons is a cousin of the free rider problem and the prisoner's dilemma, not a synonym. A free rider enjoys a good without paying for it. In the commons, everyone pays, through a shared resource that each of us has reason to use a little too much.

Tragedy of the Commons examples: where it shows up

• At work: the shared engineer, the shared budget, the shared inbox: everyone draws on it and no one is paid to protect it.
• With money: the public purse each of us wants a little more from, and the deficit that nobody chose.
• In the news: fishing fleets empty a sea that belongs to nobody, and each government is only defending its own boats.

Where it sits

Concept 2 of 5 in The Fabric of Society, a journey in the course How the World Works.

See where Tragedy of the Commons sits on the sky →

Nearest on the sky

• Collective Action
• Game Theory
• Institutions
• Moral Hazard
• Nash Equilibrium
• The Prisoner's Dilemma

A filled dot marks a star that is already open to walk.