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On The Malthusian Views Of Carl Safina

Tim Worstall, Forbes

Economic growth is the best way to limit the future number of people.

Carl Safina seems to be taking issue with the views of Matt Ridley. I’m not unbiased here as I know Ridley: indeed, I’m actually mentioned in the specific piece that Safina is complaining about. So be warned that I’ve obviously already got a dog in this fight. However, the error in Safina’s views is simple enough to comprehend. He seems to think that population is exogenously determined: that how many people there are is unrelated to the standard of living they have and thus the size of the economy. Both Ridley and I would insist the opposite: that the size of the global population is endogenously determined, it is a function of how large the economy is and thus of the standard of living of those people.

And that, really, is it in the difference between the two worldviews. From that one simple difference all else flows. Safina says:

Because such people as my old girlfriend and economists presuppose that unlimited economic growth is necessary and also believe adding billions more humans to the world is desirable, I would like to share some thoughts about such thinkers, whom I’ll call “Growthers.”

Why do Growthers think we should add billions more humans to the world? Do they want more consumers? Or is it something deeper, more biblical, more fruitfully multiplied? All of the above? Whatever their impulse, compulsive craving for “no limits” to economic growth and human numbers is irrational. A finite planet comes with limits.

If we are to assume that I’m one of those “Growthers” being complained about then that description is simply wrong. For I don’t desire infinite numbers of people, nor even ever rising numbers. However, I do desire a growing economy because that is, from human experience, the best way to limit the future number of people. Even a casual glance at historical demographics will show that: that as people become richer, as fewer of their children die in their youth, then people have fewer children and, after the demographic shift, population begins to decline. As an example there isn’t a single rich world nation that, absent immigration, will not have a declining population in the decades to come. Not one single one. And there are few middle income ones of which this will not be true too. The reason is quite simply that a goodly portion of the world has gone through that happy income barrier where people decide, all for themselves, to have fewer children.

Safina again:

The Green Revolution solved the food production problem of its time. It did not solve hunger because we did not achieve the family planning revolution needed with it. Had we stayed for the main event — stabilizing population — the whole world might have reached a wonderful sweet spot in nutrition, health and security. What we got was billions more people and, consequently, more people living with hunger and poverty.

Plenty of places did get serious about family planning. Indira Gandhi ran sterlisation programs for example: didn’t have much effect on the Indian birthrate. For here’s the little secret about contraception: the availability of it only ever accounts for some 10% of changes in fertility. The other 90% comes from peoplewanting to change their fertility levels. The logical proof of this is simple enough: fertility levels began to drop significantly for the first time in 19th century France, long before the invention of reliable artificial contraception. And they dropped in most of early 20th century Europe as well, long before the pill.

Now quite as to why richer societies desire fewer children economists have a whole parcel of possible reasons. The invention of pension schemes means that a large family isn’t necessary in order to ensure care in your old age. A richer society means there are more interesting things to do than continually pop out children, meaning the opportunity cost of having them is higher. Public health measures and vaccines mean fewer die young, lowering the number of children it is necessary to have to ensure grandchildren (whether you take your guidance from the Bible or Darwin, that is pretty much the meaning of life). We can go on through any number of other reasons. But the evidence is there before our eyes: in richer societies fertility rates drop simply because people desire to have smaller families.

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