Living Within Limits: Ecology, Economics and Population Taboos.

• Author: Bailey, Ronald

THE FEAR OF "OVERPOPULATION" UNderpins most contemporary environmental alarmism. This is chiefly a result of biologist Paul Ehrlich (of The Population Bomb fame) and ecologist Garrett Hardin, whose latest book, Living Within Limits, continues the argument that the world is running short of resources, options, and time. Unfortunately for Hardin (but perhaps fortunately for the rest of us), Living Within Limits is no more than a theory begging for supporting evidence.

Hardin secured his rank as one of the world's leading ecological thinkers with his seminal 1968 essay, "The Tragedy of the Commons." By analyzing what happens to commonly held grazing lands, Hardin illustrated that herdsmen have no incentives to restrain the number of cows grazing on the commons. In fact, the reverse is true: If a herdsman doesn't put a cow on the land, his neighbor will, and thus reap the benefits of raising an additional cow. This "logic" leads inexorably to overgrazing and the eventual destruction of the common pasture land. Hardin concluded that only "mutual coercion, mutually agreed upon" could prevent this apocalyptic outcome. He also argued that a number of today's serious ecological problems, such as air pollution, overfishing of oceans, decimation of whales, devastated forests in Nepal, and desertification in Africa, result from "the tragedy of the commons."

Despite his useful analysis of the "tragedy," Hardin failed to understand the problem lies with the "commons," not the herdsmen. Consequently, he opted for regulating herdsmen instead of abolishing the commons. History, however, shows that the better way to avoid the tragedy of the commons is through privatizing resource ownership. If individual herdsmen can fence in portions of the commons and secure ownership rights and responsibilities, their incentive to protect it from overgrazing dramatically increases.

This is precisely why modern free-market environmentalists propose that private owners, whether individual or group, commercial or non-commercial, offer the best defense against environmental overkill. Simply by protecting their property--trees, animals, aquifers, airsheds, grazing areas, and rivers--they incidentally protect the earth for the rest of us.

Unfortunately, an analysis grounded in lived experience and historical fact has always escaped Hardin, then and now. For a scientist, he is curiously uncomfortable around empirical data, declaring in a 1982 debate with economist Julian Simon...