Monday, August 29, 2011

Zero Population

A recent thread at Mormon Dialogue and Discussion Board mentioned this lovely piece of nostalgia:

The poster apparently shares the same concerns as these hip 80s rebels. Given the centuries old scare of overpopulation that continues even today, it is easy for one to wonder if the Mormon emphasis on childbearing and family life is misguided. Are large Mormon families joining the ranks of the Beckhams as "bad role models and environmentally irresponsible?" Are we not worried about "improving family planning or reducing global inequality?" Do carbon emissions and diminishing resources mean nothing to us? Unfortunately for alarmists, our natural resources are doing just fine. The food supply is not "shrinking away" and the oil is not "depleting."

Economist Bryan Caplan and science writer Matt Ridley have recently taken this Malthusian view and turned it on its head by claiming that increasing population is actually a good thing. Caplan writes,

The case against population is simple: Assume a fixed pie of wealth, and do the math. If every person gets an equal slice, more people imply smaller slices. The flaw in this argument is that people are producers as well as consumers. More sophisticated critics of population appeal to the diminishing marginal product of labor. As long as doubling the number of producers less than doubles total production, more people imply smaller slices. These anti-population arguments have strong intuitive appeal. But they face an awkward fact: During the last two centuries, both population and prosperity exploded. Maybe the world just enjoyed incredibly good luck, but it makes you wonder: Could rising population be a cause of rising prosperity? Yes. Economists’ central discovery about economic growth is that new ideas are more important than labor or capital. The main reason we’re richer than we used to be is that we know more than we used to know. We know how one man can grow food for hundreds. We know how to build flying machines. We know how to build iPhones. Best of all: Once one person discovers a new idea, billions can cheaply adopt it.

Matt Ridley refers to this as "ideas having sex." The way ideas mate, according to Ridley, is exchange. Increased exchange and specialization (i.e. market systems) lead to increased productivity and, consequently, the rise of living standards. "The poor in the developing world grew their consumption twice as fast as the world as a whole between 1980 and 2000…Despite a doubling of the world population, even the raw number of people living in absolute poverty...has fallen since the 1950s. The percentage living in such absolute poverty has dropped by more than half to less than 18 percent."[1] In fact, it was labor's shift from the family to the market that made it plausible for couples to consider having less children.[2] As Ridley notes, "Human beings are a species that stops its own population expansions once the division of labour reaches the point at which individuals are all trading goods and services with each other, rather than trying to be self-sufficient. The more interdependent and well-off we become, the more population will stabilise well within the resources of the planet...Most economists are now more worried about the effects of imploding populations than they are about exploding ones."[3] Birth rates worldwide have been falling since the 1960s, with "the raw number of new people added each year...falling since the late 1980s" (this is across all cultures, including Mormons).[4]

As of now, if the entire population were to live within the density equal to that of New York City, we could all live here in Texas. The Economist has estimated that each subsequent billion will take slightly longer to reach and that the global population growth will plateau at about nine billion people in 2050. "A 2003 assessment by the United Nations concurs," writes RealClearScience editor Alex Berezow. "The UN projects, under its medium-growth scenario, that the human population will remain relatively stable at 9 billion until the year 2300." Wheaton business professor Seth Norton has documented the effects of liberalized economic institutions on fertility rates: high economic freedom and the rule of law (thus, higher economic growth) tend to lead to lower fertility rates.[5] Or, as Reason's Ronald Bailey summarizes, "economic freedom actually generates an invisible hand of population control." It was this kind of evidence that convinced business professor and economist Julian Simon decades ago to make a wager with alarmists: "select any raw material you wanted - copper, tin, whatever - and select any date in the future, "any date more than a year away," and Simon would bet that the commodity's price on that date would be lower than what it was at the time of the wager."

[Environmentalist Paul] Ehrlich and his colleagues picked five metals that they thought would undergo big price rises: chromium, copper, nickel, tin, and tungsten. Then, on paper, they bought $200 worth of each, for a total bet of $1,000, using the prices on September 29, 1980, as an index. They designated September 29, 1990, 10 years hence, as the payoff date. If the inflation-adjusted prices of the various metals rose in the interim, Simon would pay Ehrlich the combined difference; if the prices fell, Ehrlich et alia would pay Simon. Then they sat back and waited. Between 1980 and 1990, the world's population grew by more than 800 million, the largest increase in one decade in all of history. But by September 1990, without a single exception, the price of each of Ehrlich's selected metals had fallen, and in some cases had dropped through the floor. Chrome, which had sold for $3.90 a pound in 1980, was down to $3.70 in 1990. Tin, which was $8.72 a pound in 1980, was down to $3.88 a decade later. Which is how it came to pass that in October 1990, Paul Ehrlich mailed Julian Simon a check for $576.07. A more perfect resolution of the Ehrlich-Simon debate could not be imagined. All of the former's grim predictions had been decisively overturned by events. Ehrlich was wrong about higher natural resource prices, about "famines of unbelievable proportions" occurring by 1975, about "hundreds of millions of people starving to death" in the 1970s and '80s, about the world "entering a genuine age of scarcity."

This brings us to the final point, which is made perfectly by Caplan: "Libertarians could celebrate these changes as proof that the problem of overpopulation solves itself whether or not governments do anything about it. But if Julian Simon and the intellectual tradition he inspired were right, libertarians should be experiencing severe cognitive dissonance." We should continue to want children despite our economic success (success which allows us to actually afford more children). One does not have to take the Tiger Mom (Caplan has been called the "Anti-Tiger Mom") approach of "no time, no bucks, no fun." Having children should be encouraged for both social and private benefits, as Caplan has recently argued.[6] Not to mention it appears to be the first commandment given following creation.

Be fruitful, and multiply, and replenish the earth... (Genesis 1:28)

UPDATE: Ronald Bailey's latest (Aug. 30, 2011) Reason article reviews the recent data on trade, prosperity, and fertility. In conclusion, he states, "In the modern era, trade liberalization promotes a virtuous cycle that boosts incomes, raising the value of education, resulting in the protection of women’s rights, and eventually inducing a fall in fertility rates." Also, thanks to Tyler Anderson for pointing out Elder Nelson's comments on overpopulation. Mike Gallagher has an informative article over at BBC, while Matt Ridley and Nicholas Eberstadt chime in on reaching the 7 billion mark. A Catholic philosopher weighs in on Caplan's theory, while another stresses fact checking.


1. Matt Ridley, The Rational Optimist: How Prosperity Evolves (New York: HarperCollins, 2010), 15.

2. For an overview of the effects of capitalism on the family structure, see Steven Horwitz, "Capitalism and the Family," The Freeman 57:6 (July/Aug 2007).

3. Ridley, 2010, 211.

4. Ridley, 2010, 205.

5. Seth Norton, "Population Growth, Economic Freedom, and the Rule of Law," PERC Policy Series PS-24 (Feb. 2002).

6. Caplan's newest book is Selfish Reasons to Have More Kids: Why Being a Great Parent Is Less Work and More Fun Than You Think (New York: Basic Books, 2011).

1 comment:

  1. Walker,

    I'm glad I decided to stop by your blog again. As always, you provide an intelligent, insightful post. (The nostalgia break was amusing as well, by the way).

    It's good to know that intelligent people have seen through the story crafted to drive certain agendas: I've long maintained that "overpopulation" is nothing more than a commonly-believed lie.

    Perhaps I'll have to blog about this as well, though I can't improve on what you've written.