How Many People Does The World Need?

by Patrick Appel

Gary Becker highlights the economic advantages of population growth:

To be sure, if higher birth rates lead to lesser education and other human capital investments in each child, they may result in lower, not higher, per capita incomes. Malthus fear of lower per capita incomes explains his strong opposition to high birth rates. However, the rapid growth in world population during past 250 years has been accompanied by unprecedented high per capita incomes all over the world. Whatever the Malthusian negative effects of greater population, they have been dominated by factors that raised per capita incomes, including the benefits of increasing returns and other advantages from having a larger population.

Richard Posner disagrees:

There is no necessary connection between population and economic growth. The sharp decline of Europe’s population because of the Black Death is thought to have increased per capita incomes significantly by reducing the ratio of people to arable land, resulting in improved nutrition. A larger population can, as Becker points out, increase the rate of technological progress by increasing the number of geniuses and other very creative people. But so can assortative mating, which has become much more common in the advanced countries as a result of falling discrimination and Internet dating search. At some point there may be diminishing returns to the increasing number of computer engineers.