My grandmother was born in Dallas in 1896, when the city had about 40,000 people. Her mother and father had moved there 20 years earlier, from Alabama and Massachusetts, respectively, and it was even smaller then. Dallas was much bigger, with nearly 200,000 residents, when my grandfather moved there from Missouri in 1920. The two of them married in 1923 and spent 65 years together as Dallas continued to grow into one of America’s biggest metropolises, with 7.5 million people as of this writing.
My grandfather was a Dallas booster of the first order - volunteering for city commissions, recruiting businesses and people to move there, and taking pride in every new skyscraper. I visited his law office in 1978, on one of the top floors of a downtown tower, and he proudly mapped out the history of Dallas’s growth, like rings on a tree, as we looked out of his window. I chauffeured him around for a week in 1983 and he made a special point of showing me buildings that had gone up since my last visit. Dallas was a great place, he thought, and he wanted to share it with as many people as possible.
My grandmother had a different view. There were already too many people on earth, she thought, and she wanted those already here to stay away from Dallas. “All this development just makes me sick,” she’d say to my grandfather, and she meant it literally. When she learned that my aunt would have a fourth child, for instance, she went directly to the bathroom and threw up. She later became a doting grandmother in her way, telling my cousin that "you're so cute and I didn't even want to like you." Still, I must assume that the news of my birth, six years later, caused her additional gastric distress.
Concerns about overpopulation were of course never restricted to my grandmother. My parents had a whole bookshelf devoted to the topic, including the 1968 best-seller The Population Bomb by Stanford biologist Paul Ehrlich and 1972’s Limits to Growth by MIT professors Dennis and Donella Meadows. The 20th century had brought us antibiotics, better vaccines, and the Green Revolution, with attendant improvements in life expectancy and child mortality, but these authors believed that the extra people would soon drive us into famine, plague, and war. We needed to turn off the population spigot, they argued, or there would be hell to pay as we quickly depleted our resources. It made a lot of sense to my childhood self, as Ehrlich’s book loomed ominously on the shelf next to Rachel Carson’s Silent Spring and Nevil Shute’s On the Beach.
I was therefore pleased to be assigned the task of reviewing Limits to Growth in my senior population economics seminar in 1984. I went into the project assuming that the alarmists had been proven correct, that population had continued to rise exponentially and that resources had become even more scarce and expensive. I believed it when the Meadows said that “the most probable result will be a rather sudden and uncontrollable decline in both population and industrial capacity.” But I quickly learned that we were almost all wrong, both the alarmists and myself.
The alarmists of my youth thought that world population would explode unless we implemented heavy-handed anti-fertility efforts. With the exception of China and its one-child policy, however, these policies were never implemented. So the world’s population continued to explode, right? Mostly not. The world’s population has grown since 1970, but the rate of growth has slowed dramatically, from about 2.2 percent per year in 1960 to about 1 percent today. This is mostly due to a lower fertility rate, defined as the ratio of births per woman. The world’s fertility rate has declined from about 5 in 1960 to about 2.3 today, with a rate of 2.1 implying a stable, long-run population.
Today’s rich countries have especially low fertility rates - the United States at 1.7, Spain and Italy at 1.3; and Japan at 1.4. South Korea has a fertility rate of 1.0, meaning that each successive generation will be half the size of its predecessor. Rates are higher among today’s poor countries, but their fertility rates are falling, too, and so the world’s population will likely top out at around 11 billion people in 2080. So the alarmists were right that population would soon peak, but they were quite off about the attendant death and destruction.
The 1970s alarmists also claimed that we'd soon run out of resources like oil, coal, and iron. This made sense to my childhood self, in part due to the oil crises of the 1970s, and in part because there really is a finite set of anything on this planet. But this claim has been proven especially wrong in the ensuing 50 years. We find new stuff faster than we use the old stuff, in part because we invent new methods of extraction, as with the shale gas revolution of the past few decades. It seems that useable natural resources have become more available, not less.
Economist Julian Simon’s The Ultimate Resource, published in 1981, was the main text for my population economics class, and it was largely a rebuttal to the alarmists. Indeed, Simon’s titular resource is not coal, iron, or oil, but people, which Simon saw as the thing in shortest supply. A larger population might create more problems, Simon argued, but those extra people would solve more problems than they created. They would invent new technologies, they would cure more diseases, and they would even find more resources.
Simon was something of a depressive, and he characterized this book as a piece of auto-therapy, an attempt to regain some optimism about the world and his own life. Whatever the cause, Simon made the case for resource optimism, and in 1980 he bet Ehrlich that the relative prices of five metals would come down over the next ten years, an indicator that, relative to people, commodities were becoming less scarce, not more. Ehrlich eagerly took the wager, but Simon won the bet with ease. Simon died in 1998 but, had he lived, he would have won the bet twice over in the ensuing decades.
The alarmists were mostly wrong about pollution, too. The world is cleaner in many ways than it was 50 years ago, with less polluted air and water in Europe and North America, for example. It appears that, upon reaching a certain level of wealth, countries start to spend their extra money on improving rather than degrading the environment. Newly middle-income countries, like China, have become more polluted in the ensuing years as their economies developed, but I’m optimistic that they will also soon develop a taste for a cleaner environment, too.
The alarmists were correct, however, about greenhouse gases. The continued increase in carbon emissions over the past 50 years has created serious climate problems, somewhat along the lines envisioned by the alarmists. Climate change is a special challenge, too, because, unlike smog over Los Angeles, the solution requires coordination between countries with quite disparate interests. Our political institutions, particularly our international ones, have not yet been able to resolve those conflicts. On this and related issues, such as mass extinction, the alarmists made some points that have stood up to time.
The alarmists were wrong about one more thing, however. The alarmists believed that virtually all economic growth, all improvements in our material lives, arose from throwing more stuff – labor, minerals, power, land – at the production line. But this is mostly wrong. Most of our economic growth comes from new ideas, from inventions of methods that create more valuable products out of the same resources. As just one example, cars today are almost infinitely better than the Model T, not because they include more steel, but because we’ve figured out how to build a better car. It’s new ideas that make life better.
New ideas come from people, of course, and we get more and better ideas if we have more people. Paul Ehrlich started the Zero Population Growth organization in 1968, though its real goal was to actually decrease the world’s population. The organization still works to increase awareness about the dangers of overpopulation and lobbies for governmental provision of birth control and abortion services. They’re not all wrong, of course, but they surely talked some couples out of having a 2nd child – in Canada, in Korea, or perhaps in Zambia - and one of those non-children might have resolved an important problem in nuclear fusion, and that non-invention might have given us all clean, safe energy.
Although neither the alarmists (in the 1970s) nor myself (in that seminar) talked about it, there is another problem with negative population growth, one that demographers have come to better appreciate as more countries have very low fertility rates. The problem is that much of our methods for taking care of old people – whether provided by families or by hired aides – is reliant on having a large ratio of youngsters to oldsters. Lower fertility reduces that ratio and therefore leads to higher costs for nursing care, later retirement dates, and stresses to pension systems. My father died a year ago this month and, in his declining years, I was fortunate to share his care with the aides and friends at his retirement community and with my three siblings. Paul Ehrlich is now an old man and he likely has good support. I hope he doesn’t take it for granted.
It would have been interesting to have my Dallas grandparents in that seminar room as I embraced Julian Simon and criticized the alarmists. The presentation went well and, on its basis, Prof. Kelly wrote a letter that got me into the University of Chicago’s graduate economics program despite my mediocre grades. My grandfather would have liked my talk, thinking to himself about all the wonderful things those extra people were going to invent, write, and build, but my grandmother would have thought Julian Simon a hopeless optimist, and I can imagine her grimacing as I talked about the benefits of more people. I might even have made her sick.
Well thanks, you learn something every day. Well on a good day.
Will This is cool. Sounds like we both travelled a similar journey. My first mineral economics class in 1979 (my major) was an explicit takedown of Limits to Growth. Somewhere around here I have a Julian Simon books that he noted and autographed for Mancur Olsen. I was always the population optimist (we can always tax away wasteful externalities after all). But I agree climate change is a different animal than resource exhaustion.