Garrett Hardin – Tragedy of the Commons – Key Papers #1

In this post, I will start a series of discussing papers that I regard as influential to environmental engineers (or at least to the areas of environmental engineering that I have devoted attention to).  The first paper I discuss is Garrett Hardin’s paper, “The Tragedy of the Commons”, which was published in Science in 1968.

Garrett Hardin was a professor at the University of California – Santa Barbara, who died in 2003.  Wikipedia has a very nice biography.  1968 was two years before the first Earth Day.  While Hardin’s main objective was to look at the problem of overpopulation, he tackled in his paper the subsidiary problem of why is there pollution.

Hardin’s central metaphor is the idyllic Commons — traditionally a plot of land in a village — in which anyone was free to graze their animals.  It was in the interest of every individual to maximize their use of the Commons (adding animals), yet if everyone behaved in such a manner, the Commons would be ruined beyond its carry capacity.

In economic terms, the negative externality of use of the Commons was not passed back to each individual fostering overexploitation.  Therefore there was no incentive not to overuse the resource.

Analogies to pollution control are abundant – if the ability to dispose into the air, water or soil is treated as a free asset, then there is every incentive to overexploit such asset.

What can be done?  Hardin suggests that, agreed moral coercion in the form of regulations, taxes, or regulation are needed, but he recognizes the inherent conflict between liberty and such strictures.

Hardin wrote a re-examination of the paper in 1998 – 30 years later.  He fundamentally reiterated the main messages, but realized that he perhaps should have titled his paper “Tragedy of the Unmanaged Commons”.  He wrote (in 1998):

Its message is, I think, still true today. Individualism is cherished because it produces freedom, but the gift is conditional: The more the population exceeds the carrying capacity of the environment, the more freedoms must be given up. As cities grow, the freedom to park is restricted by the number of parking meters or fee-charging garages. Traffic is rigidly controlled. On the global scale, nations are abandoning not only the freedom of the seas, but the freedom of the atmosphere, which acts as a common sink for aerial garbage. Yet to come are many other restrictions as the world’s population continues to grow.”

Now, 45 years after the original paper, 15 years after the restatement, and 10 years after Hardin’s death, the message remains true.  Unrestricted exploitation of a commons will inevitably lead to tragedy.  So a central problem of environmental engineers interacting with policy makers is how best to preserve and enhance the assets that a commons presents while using the lightest footprint on individuals.