Empty Rhetoric

Empty Planet: The Shock of Global Population Decline

  • Darrell Bricker & John Ibbitson
  • Penguin Random House, 2019; 304 pages, $14.76

The most dangerous lies are half-truths. Empty Planet was written by journalists Darrell Bricker and John Ibbitson. As journalists, these men write engagingly about the state of the global population and its future. 

They get a lot of the trends and narrative correct. Unfortunately—and dangerously—they also get a lot wrong.

 Empty Planet is accurate in several of its assertions. The global demography is changing rapidly and the old narratives about population have aged poorly. The 20th century was unique in the history of humanity, and the 21st is shaping up to be just as unique. The demographic transition—the move from high fertility and high mortality to low fertility and low mortality—emerged in the 1700s but really picked up speed in the 20th century and spread to every population on earth. For the first time in human history, decreases in infant and child mortality made dramatic and sustained progress, declining from several hundred deaths per thousand children to tens per thousand. As a result, life expectancy (the sum of age-specific mortality rates) skyrocketed, rising from 20-30 years to 40, 50, even 60 years over the course of a generation. During this period, the population grew rapidly. Some even said it exploded, but fertility also began to decline and so, too, did population growth rates.

The demographic transition is not a Western phenomenon, nor is it something that happened to “us” but not to “them.” Mortality has declined in every population on earth. With the exception of one country (Niger), fertility has also declined everywhere. Half of the world lives in a population with below-replacement fertility. Even in populations with above-replacement levels, fertility is lower than it was a century earlier.

This change, however, did not occur uniformly. Populations have varied in the timing, level, and pace of their demographic transition. The global centers of growth and power are shifting. Some populations (such as those of Western Europe) started the transition earlier, completed it, and have now entered into what demographers call the “second demographic transition.” These populations are aging, and some are already shrinking. For the first time in human history, declining populations co-vary with health and wealth, not with plague and strife. Much of East Asia and South America began the transition later, but experienced in several decades the rapid decline in mortality and fertility that took over a century in Europe. These populations experienced a large youth bulge followed by rapid aging. Sub-Saharan Africa, by contrast, is experiencing the transition more slowly than East Asia or South America did, and is still in the phase wherein fertility is catching up with the recent declines in child mortality. These populations are still young and quickly growing. The U.N. projects that more than half of the global population growth in the next century will come from Africa. The global variation in age structures between populations is unprecedented.

These demographic changes do not occur in a vacuum, but rather hand-in-hand with equally momentous strides in industrialization, public health, education, and urbanization. With such rapid change, it is easy for correct ideas to become quickly outdated, and for partially correct ideas to become grossly erroneous. Hence, the field of demography is ripe for the “everything you know is wrong” genre. Yet Empty Planet gets too much wrong to redeem what it gets correct.

With an erudite writing style, the authors crudely attack a straw-man version of the U.N.’s population-projection methods. They claim that urbanization is the cause of fertility decline, and since the U.N. has ignored urbanization, its projections must therefore be wrong. This logic is flawed on several counts. First, although urbanization does contribute to fertility decline, one would be hard-pressed to find any social scientist who claims that urbanization alone causes fertility to decline. If decline were due to urbanization alone, then why has fertility also plummeted in rural areas? The urbanization-causes-fertility-decline reasoning might be an acceptable generalization if it were not the crux of the authors’ argument. They give a slap-dash and unsatisfying description for why fertility declines and then hang their argument on it.

Second, the authors argue that the U.N. projections are wrong because the U.N. has ignored urbanization. This is false in two ways. It is false, first, in an obvious way: The demographic experts at the U.N. population division are aware of urbanization. Indeed, theirs is the only projection agency in the world that produces disaggregated projections by rural and urban population. The notion that urbanization simply has not occurred to them is ridiculous.

The claim is also false in a less obvious way. It is true that the U.N. does not explicitly account for urbanization in its models. But no projection agency in the world does. Why not? The U.N. (like most other projection agencies) examines past trends in fertility and mortality. Since urbanization has occurred in the past, its effects on fertility are already incorporated into past fertility trends. The same is true for democratization, education, industrialization, and every other socioeconomic variable you can think of and measure as well as the ones that you cannot. Rather than trying to model each of these variables explicitly, most projections observe their effects on fertility and mortality in the past, and therefore absorb these effects by projections from past trends. Most demographers defend this approach since trends in these socioeconomic variables are harder to predict than are fertility and mortality themselves. 

Third, the authors of Empty Planet write that the U.N.’s projections assume “that the rate of fertility decline is constant between countries and regions and that country A will always mimic country B.” This is blatantly false. The U.N.’s models explicitly include separate variables for differences in the starting levels of fertility decline: in the end levels, in the overall pace, and in the acceleration and deceleration of pace of fertility decline. 

This book review, however, is not a defense of the U.N.’s projection methods. There are legitimate reasons for which the U.N.’s methods could be (and are) critiqued. There are also other global projections besides the U.N.’s, projections which use different methods, make different assumptions, and produce different estimates of the future global population. Empty Planet considers one such other set of projections: those produced by IIASA (the International Institute for Applied Systems Analysis) in Vienna. Yet, the authors of Empty Planet give unsatisfactory reasons for why a consumer of projections should choose those produced by IIASA rather than those produced by the U.N. In fact, it seems that the authors favored the IIASA projections simply because those projections best fit their narrative and rationalized the methods—rather than examining the methods, picking the best one, and examining the results. Some of the brightest minds in demography are involved in producing population projections, and there is genuine debate about which methods are best. Yet Empty Planet has nothing to say to them or to the lay reader who is seriously inquiring into the future of the global population.

The tip-off that the authors of Empty Planet picked IIASA’s projections over the U.N.’s for ideological reasons comes from the fact that although IIASA’s projections better fit the authors’ narrative, they are by no means compatible with it. The authors of Empty Planet analyze population collapse. Yet IIASA (which of all projecting agencies estimates the least growth) predicts that the world population will peak at around 9.4 billion, then start a slow decline toward 9 billion people by the end of the century. Yes, these numbers are very different from the U.N.’s estimates. The U.N. projects that the population will continue to grow to the end of the century and hit more than 11 billion people. Yet the gap between the U.N. and IIASSA’s results is smaller than the gap between the narrative of Empty Planet and the actual results from IIASA’s estimates. A “slow decline” is not a population collapse. A planet of 9 billion people is not an empty planet; it is a billion and half more people than there are today. The conservative estimate of 9 billion people in 2100 produced by IIASA is very different from the sensationalist picture the authors of Empty Planet paint of a world wherein “the swings will sit empty, rusting. No children screaming up and down the street . . . we will grow fewer.” There is a huge difference between a slowly shrinking population and a collapsing population, between a smaller population than humanity’s peak and an “empty planet.” Yet this book fails to make any such distinctions.

Some populations are shrinking and others soon will begin to shrink, and the authors capitalize on these populations with poignant anecdotes. Yet these populations—Belgians, aboriginal Australians, the Manx, the Boni—are not drivers of global population growth. The decline of these populations and cultures is a genuine problem, but it is distinct from global population decline. The authors ignore this difference and capitalize on cultural decline for sensationalized storytelling.

It is a shame that Empty Planet hyperbolizes to the point of losing credibility. Population aging is uncharted territory and deserves serious consideration. Most industrialized economies developed in an era of young populations and population growth. The implications of aging on these economies are unclear, as aging populations will affect the flow of intergenerational wealth. The most obvious examples of this flow are social security and analogous programs.

Population aging affects the home before it hits the economy. It is the result of declining fertility, which shrinks the extended family. Fewer children by adults translates into fewer siblings and cousins, then to fewer aunts and uncles. Yet even as extended families contract, children are more and more likely to grow up with living grandparents. Adults are more likely to have aging parents for whom to care, creating a caregiving squeeze on adults who are considering having (more) children.[1] All of these age dynamics on a population scale are new developments in human history. Their implications are unclear and merit sincere consideration.

Even as the global population ages, Malthusian population doomsayers persist. Rhetoric for population control endures in India even as that country’s fertility approaches replacement level (and the southern Indian states have fertility levels comparable to Europe’s). Op-eds in Bangladesh, Pakistan, and Nigeria regularly sound alarmist bells about population growth and call for action to quell childbearing. The myth of overpopulation persists in the popular mind as well as in the mind of many governing elites. When people learn that I am a demographer, the first thing they often ask is, “So, is the world overpopulated?” Empty Planet had the potential to help correct this persistent error, but instead overcorrected and lost credibility.

The authors’ sensationalism makes them easy to discount. This is a shame since they write well and could have helped to popularize correct narratives about the world population. The global demography is changing: The facts adults learned in grade school are now outdated. The world is aging. Global aging is quietly reshaping societies even as a few people still sound the misplaced alarm against rapid population growth. Demographic change is neither sudden nor obvious, but it is altering the world. Look for it in the society around you, think about it well, and read about it. Just do not bother to read Empty Planet.

Anne R. Morse is pursuing a Ph.D. in sociology and demography from Pennsylvania State University.

[1]     S.C. Watkins, J.A. Menken, and J. Bongaarts, “Demographic Foundations of Family Change,” American Sociological Review 52.3 (June 1987): 346-58.