In the 1970s, economists and demographers worried about the “population bomb” — world population was exploding, and many doubted there would be resources enough for everyone. At least two schools of thought emerged. One held that population needed to be curbed through public policy — perhaps coercively. The other school, always a minority view, held that human beings themselves were “the ultimate resource” — a phrase coined by economist Julian Simon. On his view, more people would mean more productivity and more creative minds brought to the task of providing for the species.

Since then, conditions have changed dramatically and in ways no one predicted. World population growth slowed at a pace far beyond what anyone thought possible, even in countries that didn’t adopt anti-natalist policies. Several countries are now below replacement fertility rates, and even the fastest-growing populations are slowing down.

Those who worried about the population bomb may worry a little bit less, but fans of Julian Simon shouldn’t be so pleased. This month’s lead by Bryan Caplan examines the problem of world population with a framework strongly inspired by the late Professor Simon. Caplan recommends several policy initiatives that will encourage the growth at least of the American population while protecting individual rights and respecting individual choices.

Caplan’s views here, as elsewhere in his work, are iconoclastic. We’ve invited a distinguished panel to discuss them over the course of the month: Economist Betsey Stevenson of the Wharton School, Columbia University historian Matthew Connelly, and historical economist Gregory Clark of UC Davis. Each will address Caplan’s argument using a range of methodological tools and with somewhat different political values.


Lead Essay

  • Bryan Caplan argues that declining world populations aren’t such a good thing after all. While we may have dodged the “population bomb” predicted in the 1970s, the world still benefits from more suppliers — and demanders — of new goods and services. Friends of scientific and cultural advancement should want more people around. All of which leads him to a question: Are there ways to incentivize population growth without sacrificing individual liberty? Caplan suggests several methods, including open immigration, tax incentives for children — and the direct, ultimately private argument that having more kids is more fun than most people realize.

Response Essays

  • Gregory Clark argues that, while Caplan may more or less accurately describe the history of economic development, mineral and other reserves in the West have been significantly depleted. What holds true today will not hold true indefinitely regarding food, energy, and basic mineral commodities. The balance between population growth and resources only recently tipped toward abundance, and it will likely tilt in the other direction soon.

    Clark agrees, however, with Caplan’s suggestion that on the margin, middle-class families stand little to lose and much to gain by having more children; cultural assumptions in the West likely overestimate the importance of nurture, and as a result, middle-class Americans probably do overinvest in their children.

  • Matthew Connelly reviews the history of pro- and anti-natalist policies around the world. He finds them both full of coercion, perverse incentives, misogyny, and — if states try hard enough — atrocity. Population trends, however, are very stubborn, and the payoff to such policies is low. In his words, “economists do not know where babies come from.” Not, anyway, such that they can motivate people without destroying their autonomy. If libertarians are recruited to the pro-natalist side, as Caplan urges, their enlisting could come at the price of individual liberty itself.

  • Betsey Stevenson agrees that parents are often generally less happy than otherwise similarly situated nonparents. But she casts doubt on the theory that excessive parental worry is the source of the unhappiness. The most worrying parents, those who spend the most time on childcare, are also the ones who report relatively higher levels of happiness. There is, moreover, more to life than self-reported happiness, and parents may very well have other desires and values than just this one. Neither self-reported happiness nor economic utility are all that there is to our various ideas of the good life. We still need to learn more about why parents describe themselves as less happy before we can prescribe more children and less worrying as the remedy.

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