TEN BILLION: Return of the Population Bomb?

A generation ago—no, two generations ago, already—Paul Ehrlich scared us all out of our wits with his book, The Population Bomb. It turned out to be a bomb that we gradually learned to live with. Yes, it exploded—the world’s population did double between 1960 and 2000, the shortest doubling time in human history. No—it didn’t kill us.

As University of Michigan professor Donald Lam told us in a 2011 presidential address to the Population Association of America, the shift from large families making low investments in their children to small families making high investments in their children is a fundamental dimension of economic development that gives us reasons to be optimistic about the future.

Now the population bomb is back, this time in the unlikely form of a sold-out, one-man play, entitled TEN BILL10N, at London’s Royal Court theatre. I haven’t seen the play, but I would like to comment on the reviews, which, after all, are likely to be as influential as the play itself.


The thesis of the play seems simple enough. In the words of actor/scientist Stephen Emmont, “We’re f**ked.” Emmont, a professor of computational science at Oxford, goes on to tell his audience how we will be done in by the twin forces of overpopulation and climate change. More people eat more food, growing more food means more deforestation and transportation, more of those mean more CO2, more CO2 means more unstable weather, and so on.

The reviewers, including those in the Guardian (two reviews), the Independent, the Financial Times, and the New York Times, all take the play’s message pretty much at face value. More than that; they report being shaken by it. So, are we doomed? Or is a world population of 10 billion something we can handle? Here is what I think (condensed from a longer discussion in my book, TANSTAAFL.)

1. Yes, we have a big problem. Without adequate policies—ones that insist that polluters and resource users pay in full for all environmental impacts–our planet faces steady environmental degradation even without runaway population growth.
2. Yes, population is part of the problem. Population, at the margin, is not environmentally neutral. More people increase the urgency of adopting sound environmental policies. Past, smaller populations could find harmless places to dig up cheap resources and dump their wastes; future, larger populations will not be able to.
3. Yes, there is a need to act but no need to despair. The world's population, now 7 billion and counting, will not double again. The fearsome total of 10 billion or so people by the end of the 21^st century is projected to be the all-time peak. Demographic changes already in place guarantee that will be the case, barring an unexpected reversal of the near-universal trend toward smaller families. Given sound environmental policies, 10 billion people should be able to live together in a sustainable manner.

In short, we have the tools at hand to confound the mindless linear extrapolations that reviewers of the play found so frightening. I don’t know about the play itself, but there is no mention in any of the reviews of elasticity of demand, substitution in production or consumption, prices, or any other element of economic thinking. There is no suggestion that, in places where people are given the incentive, they find ways to use energy more efficiently, to change their diets, to cut back extraction and increase recycling. If we provide those incentives, the outlook changes.

True, the rational pessimist in me recognizes that market-based environmental policies are not politically popular. Too often that leaves us a choice between policies like ethanol subsidies or CAFE standards that are wildly suboptimal (which only adds to their unpopularity), or no policies at all. The lure of the free lunch is strong, even when it is free only in the short term, at the expense of our own descendants.

On the other hand, I am optimistic in the belief that market forces are not imaginary. They saved us in the past from the disasters we faced when we ran out of whale oil to light our homes and charcoal to fuel our blast furnaces. If we allow them to operate, they can save us again. Yes, that would mean unpopular measures like carbon taxes, highway user fees, and establishing property rights for ocean fisheries, but all of these have worked where tried. It is about time for each of us to take responsibility for our planet.

A slightly abbreviated form of this post was first published on Economonitor.