Living Within Limits: Ecology, Economics and Population Taboos, by Garrett Hardin, New York: Oxford University Press, 340 pages, $25.00
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 on population, "The facts are not fundamental. The theory is fundamental." Living Within Limits demonstrates the weakness of an approach so dismissive of "the facts." Time and time again, Hardin, now professor emeritus of human ecology at the University of California at Santa Barbara, is reduced to making wild assertions that have no scientific justification and to ignoring the well-known statistical information that complicates his Chicken Little scenario.
According to Living Within Limits, human "overpopulation" will soon precipitate a planetary "tragedy of the commons." Instead of an allegory about too many cows overgrazing their pasture, this time Hardin claims that humanity faces a literal tragedy because the world's burgeoning population is using up the limited resources of the earth. A modern Malthusian, he believes that animal or human populations, left unchecked by natural forces, will breed without restraint and outgrow their sources of sustenance.
Consequently, Hardin supports the Malthusian prediction that "an increase in well-being will increase fertility." But he must know this simply isn't true. If it were, then the highest fertility rates would be found in the richest countries: the United States, Japan, and the nations of Western Europe. Instead, fertility rates in these countries hover around replacement level. And as Third World countries begin to share in the wealth of a global economy, their fertility rates are likewise declining. Fertility rates in Thailand, Sri Lanka, and Indonesia are down 46 percent, 28 percent, and 39 percent, respectively, over the past 15 years. India's has dropped more than 25 percent since 1980 and Kenya's has fallen 18 percent.
What's more, this century's increases in population growth rates are not the result of a never-ending, planet-depleting explosion in births. They are instead the result of dramatically lower death rates. Worldwide infant mortality rates plunged from 155 to 70 per 1,000 births and average life expectancy rose from 47 years in 1950 to 64 years in 1990. Life expectancy increased even more spectacularly--from 35 to 60 years--in countries with per-capita incomes under $400. Most demographers believe that the world is passing through a one-time jump in human population due to the rapid reduction of the death rate. They expect world population to top out at between 10 billion and 12 billion sometime in the next century.
Even if looming overpopulation isn't a problem, Hardin argues that the world's population is already too great for the earth's long-term "carrying capacity." In biology, "carrying capacity" means that any given ecosystem can support only a limited number of a single species. The usual example is the Kaibab plateau deer, whose numbers rose after their natural predators were decimated. The deer then consumed all of their available pasturage and subsequently starved to death. But human beings are not just slightly more clever than deer--they also possess a well-demonstrated ability to increase the earth's carrying capacity to support their own species.
Before 1600, the "carrying capacity" of the American continent north of the Rio Grande was only 6 million to 12 million people, most of whom lived slightly above subsistence level. Employing modem agriculture and technology, our continent now supports 300 million people in what would have been unimagined luxury two centuries ago.
The same holds true for the globe writ large. While the world's population has doubled since the 1950s, food production has tripled. The real prices for corn, wheat, and rice, which have dropped 50 percent since World War II, are the lowest prices in history. And because of increases in agricultural productivity, humanity has not had to plow down additional wildlife habitat or utilize huge amounts of scarce energy resources to grow this extra food. According to the Hudson Institute's Dennis Avery, about 50 percent of the increase in the world's farm output is a result of breeding better varieties of crop plants, not increases in energy-intensive inputs like fertilizer and tractor plowing.
Increased productivity of any sort, of course, is one of Hardin's chief bogeymen. "Perpetual economic growth would necessarily entail perpetual increase in the use of energy by human beings," he writes. But it ain't necessarily so: According to a study by the Congressional Office of Technology Assessment, U.S. gross domestic product grew at an average of 2.5 percent annually between 1972 and 1985, while energy consumption remained flat. Technological improvement, which makes vast jumps in productivity and economic well-being possible, comes close to realizing the elusive "free lunch."
But because so much of his argument depends on impending shortages of non-renewable resources such as fossil fuels, Hardin must rule out technologies that promise to make those purported limits irrelevant. This is especially the case with the much-hated nuclear option. He's against nuclear energy because he thinks it's too risky. (One wants to ask, as compared to the risks posed by expansive plans to downsize human civilization?) Despite Hardin's fears, however, there are safe ways to dispose of long-lasting nuclear wastes, such as deep-ocean dumping in which nuclear waste products would be isolated from the biosphere in thick mud for thousands of years until they were subducted under the continental shelves. Even a non-nuclear world seems pretty well set for the future. The prices of all minerals and metals have dropped 40 percent since the 1970s, and oil and gas reserves are the highest in history. As anyone knows, if things are getting cheaper, it means that they are likely to be more abundant, not more scarce.
Hardin's views on technological advancement are all the stranger given his argument that, while matter and energy are conserved, "a third entity called information is not conserved; it can grow forever" (emphasis in original). He fails to take the next step and realize that there are no definite limits on information in the form of technological advances that can be substituted for matter and energy to achieve human goals. Hardin is right in theory that, one day, shortages of some critical material could make life difficult. But he fails to acknowledge what happens next: People devise new, more efficient ways to go about the business of living.
Hardin's basic critique of modern society--that "the price of increased complexity is increased vulnerability"--likewise falls short of describing reality. All one needs to consider is the experiences of current societies. Take India's "simpler" society--where an earthquake last year killed tens of thousands of people. By contrast, the recent Los Angeles earthquake killed fewer than 70 people. Or compare how well the United States coped with the Mississippi River flooding to the devastation that flooding regularly brings to Bangladesh. Just as in ecosystems, complexity in economies creates greater resilience, not less.
After reading Living Within Limits, it's easy to see why Hardin doesn't think too highly of "the facts"--they keep getting in the way of his theory. Life on planet Earth, while far from idyllic, is by most measures certainly getting better for more and more people. In ignoring that central fact, Hardin fails to heed his own admonition for "clear thinking" about the population issue.
This article originally appeared in print under the headline "Malthus for the Modern Man".