In the summer I watch ruby-throated hummingbirds fly and hover near a feeder that my wife, Dot, carefully fills with nectar and hangs in view of our kitchen window. The store-bought nectar is colored red, since people think that hummingbirds find that color attractive.
Business around the feeder picks up following rains that wash away the birds naturally provided food. It is then that the feeder becomes crowded and a hummingbird struggle ensues. Almost always, there is at least one bird that attempts to control access to the feederwhat naturalists sometimes call a dominant male.
The dominant male seeking to maintain control will fly rapidly to the feeder, place his beak into the small openings for a quick draft of nectar, and then fly to a nearby perch where he vigilantly monitors the feeder. When other birds attempt to feed, he quickly tries to intercept and force them away from the stock of sweet food. But while he engages in dogfights with one bird, another often swoops in and takes its fill.
The feeder is a commons, but not just for hummingbirds. Bees are attracted to it as well, and oddly enough, they can drive off the larger hummingbirds. So even if the dominant bird is able to deflect competition from other members of the species, that is not enough to protect the nectar, and the defense itself is costly in energy burned. The feeder contents are never secure.
Hummingbirds have no way to stake a claim to the feeder. So far as we can tell, hummingbird communities have no constitution that reflects socially evolved rules for establishing a social order. Most likely, a long process of adaptation and selection has generated a hummingbird capable of living in a world where nourishment is a common-access resource, a commons. Hummingbirds live a life of flight, engaging in a constant search for nourishment to feed their high-energy lives and, at times, fighting for temporary control over valuable resources.
We all know the tragedy of the commons story. Wonderfully written by Garrett Hardin in 1968, the highly stylized rendering is about a pasture devoid of rules, customs, or norms for sharing.1 It is open to all comers. In this never-never-land, shepherds logically add sheep to their flocks as long as doing so adds an increment of gain for the particular flock. Uncoordinated in their effort, and unaware of the effects of their individual actions on others, the unconcerned shepherds collectively destroy the pasture. What could be a story of plenty, if only the shepherds understood, turns into a story of poverty. The passive shepherds are like hummingbirds.
As Hardin artistically puts it: Therein is the tragedy. Each man is locked into a system that compels him to increase his herd without limitin a world that is limited. Ruin is the destination toward which all men rush, each pursuing his own best interest in a society that believes in freedom of the commons.
Garrett Hardins words beautifully bundle aspects of an endless human struggle to form communities, accumulate wealth, and improve well-being. With that phrasetragedy of the commonsthe essence of the challenge hits us squarely between the eyes: When there are no property rightsformal or informalthat limit use of a scarce natural resource, human action leads inevitably to untimely resource depletion and destruction.
But people are not hummingbirds. People can build institutions that take the edge off frantic commons behavior. People have unwritten and written constitutions that help to establish social order. People can and do accumulate wealth. People communicate, invent lines of kinship, and develop customs, traditions, and rules of law that limit anti-social behavior. People define, enforce, and trade property rights. People can and do avoid the tragedy of the commons. Indeed, instead of living with tragedies, people triumph over the commons. But the triumphs are never perfect or complete. There is always another commons to manage.
The Ascent of Man
I wish to put forward the notion that encounters with the commons form the fundamental stimulus that yields, instead of tragedy, what we today call civilization. The ascent of man from a primitive existence with no wealth accumulation to life as we know it is fundamentally a story about triumph over, not tragedy of, the commons. Let me explain.
Our very existence as human beings is defined by evolved institutions for avoiding tragedies. We have names, which serve the economic purpose of identifying us as parties to contracts and agreements. Those names, first and last, form webs of communication that reduce the social cost of assigning responsibilities and liabilities. They enhance truth-telling and promise-keeping; they raise the cost of engaging in anti-social behavior. They limit a tragedy of the commons.
We have abstract symbols of ownershipdeeds, titles, and contractsthat define spheres of autonomous behavior. We speak of our homes, our cars, our clothes, our families, and our pasture. Even language has evolved to provide a possessive form that accommodates triumph over the commons.
We write and observe contracts, wills, and marriage agreements that define relationships, identify turf, and conserve wealth. We accept evolved bodies of law and law-enforcement activities to assure the integrity of our agreements. We carry papers that enable us to acquire property, extinguish debt, cross borders, drive vehicles, and communicate effectively with strangers. And we have locks, keys, walls, fences, brands, and encryption devices, all this in an effort to avoid a tragedy of the commons.
Property rights define who we are and what we have. Property rights guard others from our unwanted advances and prevent us from contributing to a tragedy of their commons.
Avoiding a tragedy of the commons is costly. The benefits must be large.
How has it worked out? Mankind has triumphed over the path to ruin on the commons. Relative to that dewy time when nomadic tribes lived on the commons, we in the Western world live in a veritable Garden of Eden. The pastures are green. The sheep are fat. The clothes racks are full. Where property rights flourish, the choice of food is almost endless. We travel with ease to the four corners of the earth. We communicate electronically at practically no cost. Where is the tragedy of the commons?
The tragedy is found where for reasons having to do with power, intolerance, or cost, human beings have not yet defined private property rights. Or, as we shall see, where evolving property rights encouraged by man the institution builder have been destroyed. What was once a triumph can become a tragedy.
Tragedies Observed and Avoided
It is not difficult to find places where the institution builders have failed. Listen to the description of the situation of the world tiger population. At the start of the twentieth century, wild tigers were widely distributed throughout Asia, ranging as far west as Turkey, as far north and east as southeastern Russia, and as far south as the Indonesian islands of Java and Bali. There may have been as many as 40,000 tigers in India alone, and the total population may have numbered 100,000 animals. Today, the largest estimate is that the total number of wild tigers is between 4,800 and 7,300.2 What explains the demise? The same author provides an answer: Command and control prescriptions for saving the tiger have largely failed because the people who actually determine the destiny of wild tigers have few incentives to save them. . . . We must convert live tigers from liabilities into assets. In short, property rights must be defined.