Thomas Malthus: Wrong Yesterday, Right Today?

Over the past five years, the world’s population has risen by roughly 80 million people annually, reaching an estimated 6.8 billion in 2009. Barring a sudden reversal in demographic trends, more than 9 billion people will inhabit Earth by 2050. Needless to say, the constellation of challenges created by population growth have placed potentially irreversible strains on the interconnected systems and cycles that comprise the Earth’s climate. Water scarcity, diminishing agricultural yields and biodiversity loss are only a few of the consequences of these forces.

These challenges have contributed to a rebirth of the profoundly misguided philosophy espoused by Thomas Malthus, an English priest and economist who lived during the late 18^th Century. In 1798, Malthus argued that human population always grows more rapidly than the human food supply until war, disease or famine reduces the number of people. He was wrong – and spectacularly so. The growth of human population, which Malthus believed had peaked during his lifetime, has risen relentlessly and rapidly over the past three centuries. Malthus did not anticipate the development of powerful new vaccines for diseases like small-pox and equally powerful advances in public health infrastructure like modern sewage systems and so forth.

Malthus’ less than impressive track-record has not prevented philosophical copy-cats from peddling similar gloom-and-doom scenarios in more recent years. In 1968, Paul Ehrlich, a butterfly specialist, argued in his bestselling book “The Population Bomb” that “the cancer of population growth . . . must be cut out, by compulsion if voluntary methods fail.” Ehrlich’s penchant for apocalyptic predictions made Malthus look like an amateur. Here are of few of Ehrlich’s fantastically wrong predictions:

• “I would take even money that England will not exist in the year 2000.” (1969)
• “The battle to feed humanity is over. In the 1970s the world will undergo famines . . . hundreds of millions of people (including Americans) are going to starve to death.” (1968)
• “By 1980 the United States would see its life expectancy drop to 42 because of pesticides, and by 1999 its population would drop to 22.6 million.” (1969)

Like Malthus, Ehrlich, who is now a professor at Stanford University, failed to appreciate the ingenuity of humanity. The green revolution, which spread enabling technologies of high-yield agriculture across the planet, resulted in doubling of grain production. While many people are undernourished today, mass starvation is rare and mass starvation that is wholly innocent of human interference virtually never occurs.

Despite these wildly-inaccurate predictions, Ehrlich – like Malthus – is no dummy. On the contrary, many of his less-provocative arguments and insights, especially those related to resource scarcity, appear close to prophetic at times. In 1997, Ehrlich argued in The Atlantic Monthly that, “Since natural resources are finite, increased consumption must inevitably lead to depletion and scarcity.”

While this logic is also susceptible to the bête noire of population-control fanatics, namely technology, it is not necessarily wrong. There are physical limits on natural resources. Take oil.  Regardless of what you think of the Hubbert Curve and peak oil theory more generally, the amount of oil on Earth is limited.  Like an individual oil field, there are only so many barrels to pump out before the field runs dry.

This has led many like Jared Diamond to shift the blame from “population” to “consumption.” In 2008, Diamond fingered consumption as the likely culprit to lead to a looming doomsday for humanity in an Op-Ed article that appeared in the New York Times:

Today, there are more than 6.5 billion people, and that number may grow to around 9 billion within this half-century. Several decades ago, many people considered rising population to be the main challenge facing humanity. Now we realize that it matters only insofar as people consume and produce . . . If most of the world’s 6.5 billion people were in cold storage and not metabolizing or consuming, they would create no resource problem. What really matters is total world consumption, the sum of all local consumptions, which is the product of local population times the local per capita consumption rate.

Wrong. Population is not the ultimate problem. Nor is consumption. Profligate waste is the problem and efficiency is the solution. Take heat.

In the United States, consumers only actually use two out of every 100 units of electricity produced – 98 units are lost as heat before reaching the end-user. Efficiency is the most important response to the many challenges facing the planet during the next century and beyond, including: global warming or any other form of climate change. Robert Kunzig makes this point about the relationship between population, resource scarcity and profligate waste very elegantly in the most recent issue of National Geographic:

The number of people does matter, of course. But how people consume resources matters a lot more. Some of us leave much bigger footprints than others. The central challenge for the future of people and the planet is how to raise more of us out of poverty—the slum dwellers in Delhi, the subsistence farmers in Rwanda—while reducing the impact each of us has on the planet.”

Yes, indeed.

Forbes