Some of the most spectacularly wrong predictions in history have been made by those who claim that overpopulation is going to swamp the planet. Thomas Malthus, a British economist writing in the late 1700s, is the most famous of these. Extrapolating past trends into the future, he predicted that population growth would inevitably swamp available food resources, leading to mass starvation. That didn’t happen — we continued to develop new technologies that let us stay ahead of the reaper.
In 1968, Stanford biologist Paul Ehrlich wrote “The Population Bomb,” warning that unchecked population growth would lead to mass starvation in the 1970s. He was just as wrong as Malthus. Global population did surge, but food production managed to keep up.
So far, the prophets of overpopulation have been defeated by technology. But human ingenuity alone can never deliver a final victory in the battle to feed the world — eventually, population growth will overwhelm the Earth’s ability to provide calories. That’s why in order to put Malthus and Ehrlich finally to rest, a second component is needed — lower fertility rates. To save both the environment and themselves, humans must have fewer kids.
Fortunately, this is happening. During the lifetimes of Malthus and Ehrlich, humans still tended to have large families, with each woman bearing an average of five children over her lifetime. But shortly after Ehrlich’s book, that began to change.
Mathusian ideas are incredibly controversial; there are articles that will proclaim that he was right and others that will point to how he got it all wrong. The critics of Malthus see that Earth and humanity will survive as fertility rates fall almost everywhere but the Neo-Malthusians see that while fertility rates are dropping, the total population of the world continues to climb. This article has many great fertility rate charts.
Questions to Ponder: What did Malthus get right? What did he get wrong?