A Tragedy of the Commons archetype occurs when multiple agents acting in rational self interest escalate their actions such that they deplete a shared, erodible resource. Each individual’s action does not create a noticeable dent, but all the commons acting together amplifies the damage, leading to a situation that none of them are happy about. This occurs because each actor that engages in the tragic behavior reaps benefits, while the costs are shared by all in the system.
For example, farmers sharing a patch of land have the incentive to purchase more cows in order to increase each farmer’s profit. But too many cows on the shared grasses leads to overgrazing, and no more grass for any cow down the line – everyone suffers. Fisherman may over-fish during one season, depleting the fish population entirely so that there aren’t enough fish left to reproduce and regrow the fish population for the next fishing season.
If we didn’t have traffic lights or stop signs today, cars at intersections would each try to cross, leading to massive traffic jams. Oil companies wanting to grow profits will compete with each other to drill for oil, not paying attention to the possibility that they may reach the resource’s limits. When a small percentage of people use health insurance-covered services, they may accumulate enough costs to exceed the current budget capacity, which may mean higher health insurance premiums for all. During emergency evacuations, every one running for the stairs can crowd the limited space and make every one slower at exiting. Even the Federal Budget is a shared resource that costs everyone (we all pay taxes). Therefore, we get into heated debates about where the budget money is going – entitlement programs, for example, benefit a particular group of people only; meanwhile, those that do not benefit from these programs often times pay the most in taxes.
Tragedy of the Commons occurs because the actors do not pay attention to the effects of their actions – there is too long of a delay. Therefore, they continue their undesirable behavior until it’s too late to undo or fix the resource. Other times, the actors are very well aware of the situation, but it is not in their interests to slow down if they recognize that others will reap all the benefits.
How to Fight It
Tragedy of the Commons can be combatted in 3 ways:
- Educating people (this can eliminate the delay in feedback between the resource depletion and the actors being aware of their behaviors causing this to occur)
- Enforcing laws limiting use of a resource
- Privatizing the resource so that each participant must pay for the the direct impact of his/her actions
Index of Archetypes:
In working on a causal loop diagram for California’s drought what strikes me is that the “Tragedy of the Commons” is caused by the _absence_ of a balancing feedback connection, until the resource is depleted. I’m not sure calling it a “delayed feedback” quite captures this archetype. Thoughts?