Tragedy of the commons, our commons

More than fifty years ago, “Tragedy of the Commons,” one of the most important essays of the Twentieth Century appeared in Science, the esteemed publication of the American Academy of Science. Garrett Hardin, the author of the article, was a professor of ecology at the University of California in Santa Barbara.

By tragedy of the commons, Hardin posits that individual members of a group acting in their own self-interest do harm to the best interests of the whole group. The original theme of the article was over-population, and Hardin’s controversial views on issues such as immigration, race, and population control resulted in harsh criticism, some well-deserved, from across the political spectrum as well as from economists and other scientists. Nevertheless, his political and racial views aside, the concept has much broader application, particularly as the world faces the challenge of climate change.

In the article, Hardin describes a grazing commons, a pasture not owned by any one individual but used by several to graze their cattle. The pasture only provides enough grass for a certain number of cattle. If each user recognizes that limitation, the commons will support all of the users. He suggests that each user will act out of self-interest rather than for the good of the group and the result will be damage to the commons, which will harm all of the users. For example, consider a commons with enough grass to support one hundred cattle, ten cattle each from ten users. If one user decides to graze an extra cow on the commons, the commons might be degraded slightly since it is now over its natural limitation of one hundred cattle, yet, the offending user will see almost a ten percent benefit by grazing eleven cattle instead of just ten. If each user thinks only of his or her self-interest instead of that of the group and adds extra cattle, the commons will soon be so over-grazed that every user will suffer.

Although Hardin’s theme five decades ago was population, the metaphor of a commons has much broader application. For example, throughout the United States, water is typically a shared commons and conflicts about its use appear frequently in the news, particularly here in Arizona. What one group uses becomes unavailable to other groups. Farmers, businesses, and urban water managers vie for the same limited resource, each of them thinking of their own interests, with the result being dropping water levels in wells and even streams and reservoirs going dry.

There are many other examples. We read and hear on television about fish populations dropping due to over-fishing. Even more common are traffic jams. In reality the roads are a commons with a limited amount of space for cars. We each make a decision to drive instead of, say, taking the bus because driving is quicker. Yet, the result is overuse of the limited resource of space on streets and highways, resulting in traffic jams, which are frustrating. Yet, a principal cause is us acting out of self-interest.

Climate change offers relevant example of how the condition of a commons is affected by self-interest. The commons in the case of climate change is the earth’s atmosphere, which is a entity used by everyone. At the same time the atmosphere is not unlimited, and its condition is affected by all of its users. Over the past two centuries, more and more carbon dioxide has entered the atmosphere as fossil fuels have increasingly been burned to power the Industrial Revolution. The amount of carbon dioxide in the atmosphere is now so large that it is causing the climate to change in drastic and damaging ways; moreover the amount continues to increase. A large majority of climate scientists believe that the situation is an existential threat to modern society and even to our species.

Although most of the world’s governments have signed various treaties and accords to reduce the amount of carbon dioxide released into the atmosphere, the amount continues to increase resulting in predicitions of dire consequences in the near future. This tragic situation is not just due to policies and actions of governments. Businesses, large and small, make statements in support of reduced carbon dioxide emissions and “sustainability,” yet those seem to be more public relations gimmicks than legitimate changes. Similarly, individuals and political groups decry what our species is doing to the planet, but their words are empty rhetoric. The reality is that self-interest outweighs the common good, even, as in this case, the common good is salvation of the biosphere. No government is willing to ask its citizens and organizations to make any sacrifice, much less to the extent necessary to substantially curtail CO2 emissions. Essentially no business is willing to forego profits and standing against the competition to take action. The same goes for individuals, many of whom deny that climate change is serious or even exists. Even when presented with mounting evidence of the absolute certainty that humans are causing climate change and that drastic action is needed immediately, the situation worsens. Cognitive dissonance is epidemic, and self-interest is the only criterion for action.

The atmosphere is more than a physical commons. It also is a metaphor for a moral commons, the obligation we have to one another, to our children and theirs and theirs, and to the other forms of life that share this world with us. We have abrogated that obligation out of our own self-interest, ignorance, denial, and plain greed. The result is the greatest tragedy in the history of our species. The future looms darkly, and we are beyond salvation.