How Many People Can the World Support? It Depends...

Along the coast where I live, at almost any time of year I love to experience the energies of various migrations of birds and of fish and whales. I think of it as the real world, as natural.

But can we distinguish real from artificial when the world has become so human-dominated that some geologists have suggested naming our time the Anthropocene, the time of people? The migrations, the weather -- when we look closely, all bear our thumbprint.

In my idealistic youth I was sometimes told to "pay attention to the real world." But there I saw a place of tedium tallied in digits and zeros, where strings of zeroes are pursued and prized. The mass delusion of business's "real world" is the faith that the ledger books capture the value and the consequences of our transactions. They don't. Yet that collective delusion is real enough to mask some very concrete things.

If people are using the world's forests, fishes, soils, freshwater and other resources something like 25 percent faster than the world can replace them, it means, basically, that the world would already be broke if we weren't taking so heavily from the future. People call it "leveraging," but a new word for delusion doesn't cure the illness.

In his prescient 1848 essay "The Art of Living," John Stuart Mill foreshadowed much of what we'll be talking about regarding what counts as progress -- and what really is progress:

There is room in the world, no doubt... for a great increase in population... I confess I see very little reason for desiring it.

If the earth must lose that great portion of its pleasantness which... the unlimited increase of wealth and population would extirpate from it, for the mere purpose of enabling it to support a larger, but not a better or happier population, I sincerely hope... they will be content to be stationary, long before necessity compels them to it.

A stationary condition of capital and population implies no stationary state of human improvement. There would be as much scope as ever for all kinds of mental culture, and moral and social progress; as much room for improving "The Art of Living," and much more likelihood of its being improved...

All the mechanical inventions yet made have... enabled a greater population to live the same life of drudgery and imprisonment, and an increased number of manufacturers and others to make fortunes.

By around 1800, when the world had about one billion people, The Reverend Thomas Malthus had become alarmed at the implications of population growth. Though water remained plentiful, vast tropical and temperate forests still stood as strangers to the saw, and the oceans shimmered with fishes that had never met a strand of twine, Malthus divined trouble brewing.

Growing at just one percent annually, a population doubles in just 70 years. The U.S. already has twice as many people as when I was born; Tokyo's greater metropolitan area -- 35 million -- now has more people than all of Canada. During the 20th century, world population quadrupled; it's now approaching 7 billion. By 2050, we'll add to that more than the total human population of 1950.

How many people can this world support? It depends how they live. If everyone gets 800 kilograms of grains annually, like Americans, then the world can carry 2.5 billion people. Problem: we passed that in 1950. The world could support 10 billion people living like Indians. Problem: most Indians want to live more like Americans. (It would be interesting to see a 70-year-old American standing next to all the food -- and everything else -- that person had consumed in their lifetime.)

Of course, before we eat our dinner, we need a refrigerator to store food. In 1980, China produced 50 thousand refrigerators; in 2004 it manufactured 30 million. We need to put the refrigerator in a house, and houses use wood. The forests of Indonesia, Burma, the Russian far-east, and Papua New Guinea will be largely gone by around 2025, and with them their birds, bugs, and Orangutans.

To buy the food, we drive to the store. The Chinese would also like to drive to the store. To have as many cars per person as the U.S., China will need 30 percent more cars than exist worldwide today. Driving them would burn 98 million barrels of oil a day (the world now produces 85 million barrels). If this can't work for China, it can't work for India -- it can't work.

We need a new, non-burning energy economy, a way of reducing population, and a way of replacing the delusion of infinite growth. That's what we need.

Dividers: Four billion people live on less than $2 per day. Nearly a billion people get less than 80 percent of the UN-recommended caloric intake; they are, technically, starving. Undernourished women annually bear 20 million underweight infants, and more than half of Indian newborns would be in intensive care if born in California. A billion and a half people are overweight.

So there are two kinds of people in the world: those who want more, and those who need more. And those who need more, want more. One-quarter of the world's people consume more than three-quarters of the world's goods. That's not fair. But as I mentioned, to give everyone an American level of material living, we'd need two and a half Earths. That's not possible.

Because forests, oceans, croplands, and water supplies are all being depleted by the number of people we have now, a grim logic appears irrefutable: As we add people, either everyone will get poorer on average, or the poor will get much poorer. Or the population will be adjusted in the usual way: with shortages, bullets, and bombs.

Adapted from: The View From Lazy Point (Henry Holt Co., New York), winner of the 2012 Orion Book Award.