Summary: We’re on our way to a far better world, one with a much smaller population. The world’s population will increase during the next 4 decades, and then begin a long steep drop. East Asia leads the way with its collapsing levels of fertility (Japan’s population has already rolled over), and the rest of the world follows. The road will be rocky unless we prepare for it. Here’s an introduction to the issue. You’ll be reading much more about this in the future.
The collapse in fertility rates is another one of these unexpected phenomena shaping our world that have been described on this website. How unexpected? To understand these things we should always look first at East Asia, where fertility has collapsed the most (or perhaps, fertility has been the first to collapse). Look at Japan. Over a quarter-century every forecast proved too optimistic. It might have found a floor. Or this might be a false hope.
Experts don’t well understand what has caused this crash in fertility — although they have confidence in their theories — and have only guesses about effective public policy responses. But they understand the seriousness of this trend. How much does a nation’s population shrink after a few generations at fertility of 1.3 (approx the current forecast for Japan)?
The 2nd generation after the present one will be only 40% as large as today’s. The 4th generation is only 15% as large. These are astonishing numbers. The worst large-scale pandemics killed 1/4 to 1/3 of the affected population. Only the most severe wars inflict such damage. Unless we take massive and effective action, this outcome is almost certain.
The rest of the developed world is following Japan’s demographic path, and the emerging nations are following still further behind. The social and economic effects are difficult to even imagine.
Benefits and damages from a population crash.
Forecasts usually focus on the economic effects. Fewer workers (and less tax revenue) and more elderly dependents probably means slower growth and fiscal deficits. And persistent inflation — or deflation, depending on the economist. Here’s a more insightful analysis: “Aging and Deflation from a Fiscal Perspective”, Mitsuru Katagiri, Hideki Konishi and Kozo Ueda, November 2014. Get used to deflation.
Our analysis reveals that the effects of aging depend on its causes. Aging is deflationary when caused by an increase in longevity but inflationary when caused by a decline in birth rate. Numerical simulation shows that aging over the past 40 years in Japan generated deflation of about 0.6 percentage points annually.
While the economic effects will be large, they are foreseeable. The social changes are more difficult to understand. What will society look like when configured to support the elderly instead of children? When women’s careers are seldom sidetracked by children, and then only briefly? Our gender roles and institutions are configured for a world very different than that we can expect to see.
History books are filled with struggles with low fertility, as far back as the empires of Hellenistic Greece and Rome. See Polybius’ warnings about demographic collapse from the 3rd century BC. Their struggles were usually in vain. Fertility declines are difficult to fix.
If we want to boost fertility, can we do so?
Fertility rates are difficult to change. The monumental social trends that produced this change — such as new contraceptives and feminism — are still in motion. Feminism is still evolving, each generation more radical than before. Another revolution in contraception lies ahead, a “male pill”, which will depress fertility still more, perhaps by a lot (we don’t know how much men want children).
But why should we see falling population as a problem? The next industrial revolution has begun, probably creating painful levels of unemployment. A falling working age population solves that problem, and the increased productivity of new tech provides a means to support the growing ranks of the elderly. Also, smaller populations reduce our burden on the environment. For more about this see Must our population always grow to ensure prosperity?
For More Information
Wikipedia has an excellent entry on sub-replacement rates of fertility. For details about the data and implications see the population website of the UN’s Department of Economic and Social Affairs, especially this summary article.
- The coming big increase in structural unemployment.
- 50 years of warnings about the next industrial revolution. Are we ready?
- Experts see that the 3rd Industrial Revolution is upon us. How many jobs will be lost?
A look at past fear-mongering about overpopulation.
“The Mark of Gideon“, Star Trek in 1969. We are excited repeatedly by these linear extrapolations of current trends, despite their long history of failure. The result is exaggerated and often false alarms, and public indifference to future warnings.