Monday, October 14, 2019

Demography vs. Creativity

One of the new Nobel Prize winners in economics, Michael Kremer, once wrote a paper titled Population Growth and Technological Change: One Million B.C. to 1990. The point was to consider two ways of conceptualizing population growth: the Malthusian view that at any given level of technology, population will rise until people are desperately poor, which makes population growth a bad thing, and a technocratic view that says the higher the population, the more inventions will be made, and therefore the faster the economy will grow.

Kremer found that while the question is complicated, over the long term, population growth is proportional to population; more populous regions grow faster. (See the graph above; the curve has flattened in modern times because we started intentionally limiting our fertility.)  This contradicts Malthus, whose model demands that population growth slow as rising populations lead to more starvation and disease.

Kremer seems to feel that this is an optimistic finding, but I disagree. I see the past 10,000 years of human history as a race between population growth and better technology. This has been a brutal, vicious struggle in which the losers are cast aside and trampled under, and any slackening in the pace of economic growth means thousands starve. Even Kremer admits that there are periods when the positive correlations in his model break down, and we can all name several. In the 1650-1800 period Europe experienced a surge in agricultural productivity driven by potatoes, maize, and improved methods, which made this an optimistic time. But the rapid population growth that resulted meant that by 1800 populations were once again bumping up against the limits, so that cold weather in 1815-1850 led to the return of famine on a scale not seen for more than a century. Everybody knows what happened to the large Irish population when the potato blight struck.

Since 1850 we have mostly been able to race ahead of the Malthusian scissors, but the cost (forests cleared, swamps drained, species exterminated, ancient ways of life wiped out) has been very high. I think modern birth control might turn out to be the most important invention in human history, allowing us to finally step out of that race and create a sustainable world. We'll see.

1 comment:

G. Verloren said...

I think modern birth control might turn out to be the most important invention in human history, allowing us to finally step out of that race and create a sustainable world. We'll see.

I mean, we've never lacked the technology to control population growth. It doesn't take much to perform a castration.

What we've always lacked is the will to control populations. We don't want to do it.

It's not just about sexual desire - there are ancient forms of castration that remove fertility while still preserving the capacity for recreational sex. The problem is that growing the population has always been more desireable than maintaining it.

On a societal scale, more people has historically always meant more power. If you have more people than the neighboring country, you have a larger pool of labor and a larger pool of manpower, and you can outcompete others either economically or militarily.

And on an individual scale, having children has historically been far more attractive than not having them, for much the same reason. Having a child means being able to put that child to work; being a parent gives you greater authority over someone than simply being their employer; the pressures of clan loyalty provides a social framework for obligating others to assist you in times of need even if they don't particularly like you or want anything to do with you; etc.

Modern birth control is a fantastic boon, and it certainly helps, but it's only one element of a much larger situation. Far more important is the fact that the traditional incentives to propagate have slowly eroded somewhat. Blood means less than it once did; child labor is no longer seen as permissable; the elderly have other options for means of support than simply their own children; construction, warfare, and agriculture have become far less manpower intensive; etc.