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Japan’s Shrinking Population

You have probably read or heard that Japan’s population is shrinking, perhaps faster than any other country in the world. According to the United Nation’s widely-respected reports, Japan’s population today is roughly 125 million. The UN is forecasting a decline to around 106 million in 2050 (18 percent lower than now) and 75 million in 2100 (67 percent lower).

East Asia Forum recently published a story by Noriko Tsuya that explains why the population is declining and what can be done to reverse the decline. In short, women are having fewer children. To maintain a stable population in any country, women of child-bearing age need to have 2.1 children (the Total Fertility Rate). Japan’s fertility rate has been falling steadily since the 1970s and is now in the vicinity of 1.4. Another factor that distinguishes Japan from most other countries with low fertility rates is a very low amount of immigration. Raising the fertility rate, Tsuya argues, will require far-reaching changes in the social role of women that make motherhood more appealing and compatible with careers in the labor force.

Most media have been treating Japan’s population decline as catastrophic. Instead, it should be treated as a blessing for the Japanese people and the rest of the world. Here’s why.

First, we need to put Japan’s population in historical perspective. At the beginning of World War II (1938), Japan’s population was around 70 million. It took about 80 years to rise to 125 million and the UN is forecasting a decline back to the same level in the next 80 years. With 70 million people the, Japan was able to have one of the strongest, most productive economies in the world. It is not obvious why Japan needs twice as many now to maintain the high standard of living its population has achieved.

Second, we need to put Japan’s population dynamics in the context of global population. In the 80 years since the beginning of World War II, Japan’s population increased 1.8 times. In the same period, global population increased 4 times, from around 2 billion then to almost 8 billion now.

Most of the scientific community believes that global warming associated with human activity represents an existential threat, meaning that even with no further increase in global population, climate change will eventually make Earth unfit for human life. If you believe this, as I do, all of us should be working to shrink the world’s population to a sustainable, or optimum, level. It is already moving in this direction because fertility rates are falling in almost every country in the world. It's also happening because of pandemics, conflicts (mostly internal wars), and social challenges ranging from opioid addiction to youth unemployment.

Third, much has been written about the threat of climate change, but not enough about the limits of natural resource extraction. Most of this discussion has been about oil and gas extraction (which has been increasingly expensive to do), and in forestry (where the destruction of tropical rain forests is proceeding at a frightening pace). As the world moves from fossil fuels to renewable sources of energy, new resource constraints are emerging, ranging from copper to rare earths. In his book Collapse: How Societies Choose to Fail or Succeed, the geographer Jared Diamond examines the case of Japan, focusing on its dependence on imported resources. In a world facing fierce competition for resources, he argues that Japan’s sustainable population may be around 70 million, sustainable in the sense of being less dependent on imported fossil fuels and other natural resources required to support household consumption levels. It will be much easier to provide energy from domestic renewable resources for a population of 70 million than a population of more than 120 million.

Fourth, there is a technology argument. Climate change skeptics suggest that some yet-to-be-discovered technologies will make it possible to stop global warming and still provide everybody with plenty of electricity. There is a related thought that a growing global population will produce more inventors so that crucial discoveries will come sooner. There are two flaws in this argument. One is that there was plenty of invention when global population was less than 2 billion. Think of Edison and the Wright brothers. The other is the fact that only a tiny fraction of the world’s population at that time had the education and institutional support needed to produce the Industrial Revolution. Imagine the amount of innovation that would emerge if half or more of a global population of 2 billion had these advantages.

Many of the fears about the consequences of Japan’s shrinking population are related to aging. It is true that as the population shrinks naturally due to the low fertility rate, the proportion of the population over the age of 65 will increase rapidly, even at an alarming rate. But these fears are exaggerated for several reasons.

To begin with, the “bulge” in the aging population will be similar to the bulge in the youth population created when its fertility was above the replacement level. This bulge will disappear as the fertility rate moves back toward the 2.1 replacement rate. Also, the increase in the old-age cohort will occur over decades, providing time to make many adjustments in the way Japanese people live and work. It is hard for us to imagine these adjustments, just as it was hard for people in the 1940s to imagine what life on Planet Earth would be like in the 2022. But these adjustments are possible with simple measures such as extending the retirement age and difficult steps such as making motherhood more compatible with an interesting work life for women. Another fundamental adjustment, I’m betting, will be to stop measuring economic progress by GDP growth and focus more on household well-being. And it seems likely that there will be some radical policy changes such as introducing universal basic income.

Instead of lamenting Japan’s shrinking population, we should study how Japan’s society adjusts over the next 80 years. There will be successful policies and there will be unsuccessful ones, providing lessons for other countries as they iterate toward an optimum/sustainable population size.

As we all face this existential challenge, let us not forget that we are the only species on the planet that is destroying Mother Earth.


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