I do think the world has a serious population problem. The world population has reached seven billion and so great a number of people places enormous pressure on the environment; it contributes for example to global warming by increasing carbon emissions as a result of burning more fossil fuel in transportation and electrical generation. But if East Asia the a population problem it is the opposite: shrinking population because of very low fertility rates. The fertility rate (the number of births per woman per year) in Taiwan, apparently the lowest, is only 1—less than half the replacement rate, which is 2.1 In South Korea the ferility rate is 1.1, in Singapore 1.2, in Japan 1.3. Oddly, in China, the only country that actually restricts population growth, the fertility rate is higher—either 1.6, as some sources have it, or 1.4, Becker’s figure—though still below the replacement rate.
If China adhered rigorously to its one-child policy, the fertility rate would be below 1, because not all women have children. So the policy, which in any event as Becker points out makes exceptions for rural families (also for residents of Hong Kong and women who have graduate degrees from foreign universities—a eugenic policy, and Singapore also has encouraged fertility among high IQ couples), must be widely flouted. It is unlikely therefore that abrogating the policy would have a significant effect on birth rates, other than in the short run. There would be a short-run bump because some families who want a second child have been deterred. But the long-run effect might well be nil. The reason is that, as incomes in China rise toward South Korean and Japanese levels, the Chinese birth rate is likely to decline regardless of government policy, offsetting any effects from the abrogation of the one-child policy. As the opportunity costs of having children rise because the value of women’s time in paid work increases, and the expense of children rises as well because of the importance of education, the number of births declines irrespective of government policy.
As Becker points out, the one-child policy distorts the male-female birth ratio, leading to a surplus of males, which is probably a bad thing given the much greater male propensity for criminal behavior; at the same time it portends future reductions in fertility rates. There is also the problem, which all the low-fertility East Asian countries are experiencing, of an increased fraction of retired people. But I doubt that the one-child policy contributes significantly to that problem, because, as I have said, judging from the experience of the countries that are most like China, ending the policy is unlikely to affect China’s overall fertility rate. If this is correct, there really is no justification for this very unpopular policy, and I would therefore expect it to be abandoned, whether formally or simply through nonenforcement.
But I do wish to question whether a fertility rate below the replacement rate should actually be thought problematic. If the current size of the world’s population is excessive, as it may be, implying not only that future population growth is undesirable but that a reduction in population may be desirable, a fertility rate below 2.1 may therefore also be desirable. There are historical examples, of which the most important is medieval Europe. The Black Death, in reducing the European population by a third in a relatively short time, is sometimes credited with Europe’s economic takeoff that gave it world domination, because by substantially increasing the ratio of arable land to people the plague substantially increased incomes, in turn increasing demand for consumer goods, stimulating transportation and urbanization, and facilitating capital formation. A large retired population can act as a stabilizing, pacifying force in a society, whereas a young population, as one observes in many Middle Eastern countries, can be a formula for instability.