Yemen Dangerous Waters Photo Essay

FILE - In this Sept. 29, 2018 file photo, fishermen rest on their boats before fishing at the main fishing port, in Hodeida, Yemen. Yemen's civil war, in which a Saudi-led coalition is fighting on the government’s side against the rebels, has pushed much of the country to the brink of famine. (AP Photo/Hani Mohammed, File)

Earth’s greatest natural resource is the human brain. And it may also be among the least appreciated, judging from the persistent doom and gloom, going back centuries, over the supposed menace of overpopulation. Wishing for fewer human brains on Earth is like wishing for fewer diamonds or rubies.

Yet few wrong ideas have been more persistent than the fear of too many people. British cleric Thomas Robert Malthus promoted the terror of apocalyptic overpopulation in a memorable 1798 treatise. Memorable, that is, for being so wrongheaded. Malthus anticipated that the population would soon outstrip the food supply; instead, the rapidly growing human race set off on a long tear of unprecedented economic growth and prosperity.

That Malthus missed by a mile did not prevent the rise of the neo-Malthusians in the 1950s and ’60s, whose fallacies reached a zenith in the runaway 1968 bestseller “The Population Bomb.” This dismal book floated ideas such as mandatory sterilization and a tax on children to save the planet. In China, such muddled thinking produced a draconian one-child policy, decreed in 1979, that will hamper the country’s growth for decades to come. Recent efforts by a more intellectually agile leadership to reverse the policy and undo the damage have seen underwhelming results.

Like the boy who said the emperor was naked, Julian Simon of the University of Maryland persistently challenged the doomsday error. In a famous 1980 wager, Simon bet an author of “The Population Bomb,” Stanford University’s Paul Ehrlich, that resources would actually become more plentiful, not less, as the population grew. Simon understood that more human brains would be at work finding new supplies, and inventing more efficient ways to grow and use them, and dreaming up alternatives to those that become scarce. Of course, he won the bet: In a little more than 10 years, the price of a representative set of commodities fell by more than half — a clear signal that supply was outstripping demand.

My gloomy human reflex almost had me write that resources grew more abundant “despite” the rise in population. In fact, resources grew “because” of the rise in population. We think we know the limits of our resources until human brains discover ways to burst those limits.

Some of the means are extractive, like freeing “tight” oil and gas through fracking, or the Japanese discovery of vast rare-earth deposits under the sea. But other solutions are renewable. Take, for example, the pressing issue of water supplies — a current concern of population catastrophists. In water-stressed places from Israel to Singapore to Las Vegas, human brains are deploying a wide variety of technologies to efficiently desalinate seawater or effectively recycle wastewater, thereby increasing the available resource. Meanwhile, modern appliances and factories are made more efficient, which reduces demand.

These advances don’t happen by magic. They happen through price signals. When a resource grows expensive, creative people figure out how to find more, create more or use less.

Swashbuckling economist Paul Romer recently received the Nobel Prize for his work in measuring the beneficial impact of human thinking, creativity and rulemaking on global abundance. Along with his co-winner, William Nordhaus of Yale University, Romer points us to the tremendous potential of a tax on carbon as the best available weapon against climate change. The tax — which could be refunded in the form of subsidies for green upgrades at home and work — is the necessary price signal to unleash the full creative powers of human ingenuity.

From immigration to climate to wealth distribution, our policy debates are dominated by doomsday and stalked by scarcity. Yet all around us, if we will look past fear to facts, we see evidence of abundance. And we can continue to have more of it for more people, if we treasure and nurture the most precious of our renewable resources: ourselves and our fellow human beings. We need only set our minds to it.

David Von Drehle is a columnist with The Washington Post.