CSMonitor | Food and people. Thomas Malthus posed them as two forces rarely in balance. Plentiful food encourages population growth. A booming population devours more food than can be produced.
Students who learn of Malthus’s grim prediction usually take away two lessons. The first is the sharp contrast between arithmetic and geometric progression. Food supplies grow slowly, Malthus said. But consumers multiply like rabbits. A geometric progression outstrips an arithmetic one every time.
The second lesson is about why Malthus’s catastrophe hasn’t occurred. Most scholars think it is because the 19th-century Anglican parson didn’t have sufficient regard for technology and innovation. From the “green revolution” to global trade, from drip irrigation to entrepreneurial ingenuity, Homo sapiens learn and improve. We farm better, manage resources more carefully, and as education increases, birthrates fall.
A wise species – which is what “sapiens” means, after all – avoids a crash. That’s the story so far. But every rise in global food prices, every scene of malnutrition and starvation revives the old Malthusian fear. Malthus himself was careful not to predict when a judgment day would come. He simply noted a distinction between unlimited progress, of which he was skeptical, and “progress where the limit is merely undefined.” In other words, the jury may still be out.
Even if there hasn’t been one big catastrophe, there have been many regional ones since Malthus’s day. Famine in China, for instance, killed as many as 40 million people between 1958 and 1961. Bangladesh, Biafra, Ethiopia, and a dozen other regions suffered terrible food shortages in the 20th century. But these were not Malthusian events where a population outgrew its sustenance. Bad decisions – political incompetence, wars, brutal experiments such as Mao Zedong’s “Great Leap Forward” – were to blame.
We have about 40 years before the jury renders its final verdict on Malthus. The population of the planet is currently 6.9 billion. By 2050, it will hit 9.2 billion, according to the US Census Bureau. Because of declining birthrates, population specialists believe that will be the peak. Whether you think more population growth is good or bad, that’s the predicted trajectory.
