When considering the issues of low birth rates and population decline, it's essential to differentiate between those who are pro-life and those who are pro-natalist.

While both have concluded that people around the world should have more children, their reasoning is almost diametrically opposed to each other.

Defining terms

Pro-lifers, often informed by Christian morality, believe in the dignity and value of each human life. They value the virtues of the nuclear family, believing it brings out the best in parents and their children. Their commitment to life and family means they vigorously oppose all forms of abortion and, by extension, in-vitro fertilization, surrogate parenting, and divorce.

In the pro-life view, lower birth rates are largely the result of cultural and moral decadence, which can be reversed only through a full reformation of social values and institutions.

By contrast, pro-natalists tend to be strict utilitarians, arguing for more children for primarily economic and political reasons. They worry about the public pensions going unsupported, schools emptying, and whole political systems collapsing due to depopulation. They fear a technological regression, a contraction in the markets, and even a revival of provincialism (or de-globalization) in a world with fewer people.

Unlike pro-lifers, they have no problems with employing artificial means of reproduction, legalizing abortion, and allowing any adult, regardless of background, to adopt and raise children for whatever reasons. In the minds of most pro-natalists, depopulation can be averted through twisting the right dials of social policy and letting go of the traditional expectations around parenting.

'No future is more likely than that people worldwide choose to have too few children to replace their own generation.'

Put more crudely, pro-lifers tend to be conservative and pro-natalists tend to be non-conservatives (which would include libertarians and moderates in addition to progressives).

Then, of course, there are the anti-natalists (usually on the political and cultural left), who believe overpopulation is a problem and oppose having more children. They believe a lower population will improve the environment and the quality of the life for those lucky enough to be alive.

'After the Spike'

Understanding these distinctions is key to understanding the latest best-selling book on depopulation, "After the Spike: Population, Progress, and the Case for People" by economists Dean Spears and Michael Geruso. This is a book by pro-natalists written explicitly for anti-natalists.

As such, the two writers end up spending more time on what they are not arguing (i.e., pro-life claims about morality and culture) than what they are actually arguing (i.e., the pro-natalist concerns about depopulation).

Not only does this approach shut out a large group of potentially sympathetic readers wanting to know more about the issue, but it also fatally undermines their main argument for stabilizing the population. Even though they use the language of anti-natalists and speak to their concerns, it’s doubtful they would even persuade the target audience since their claims are so qualified and open.

However, this is not necessarily the fault Spears and Geruso, but the presuppositions of utilitarianism itself, which prove to be wholly inadequate for addressing the challenge of depopulation.

Math over meaning

These problems begin early in the book. As the book’s title suggests, the writers mainly frame depopulation as a simple math problem. They explain how the world population will peak or “spike” in the coming decades and then swiftly drop over the course of a few generations right afterward.

Their “big claim” in the first two chapters is expressed in clinical terms: “No future is more likely than that people worldwide choose to have too few children to replace their own generation. Over the long run, this would cause population decline.”

Somehow proving this “big claim” takes up nearly a fifth of the whole book. Perhaps they do not want to be confused with Bible-thumping pro-lifers who lack their credentials and supposedly rarely bother with hard numbers. That said, pro-lifers would not deny the claim that depopulation is imminent — birth rates are below replacement, so yes, deaths will outnumber births and result in depopulation — but the anti-natalist crowd evidently struggles to accept this basic fact.

If so, this popular denial might be an interesting potential factor in depopulation to explore further, but the writers never go there. Instead, they review the usual anti-natalist arguments made in favor of depopulation: It’s better for the planet; it’s better for women; and it’s better for conserving resources.

In most cases, debunking these claims is as simple as looking at available social science data. It turns out that the world is cleaner, more equitable, and in less danger of running out of natural resources now with a larger population than it was in the recent past with a smaller population.

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Again, this point is fairly easy to grasp, but not if a person casts human beings as irredeemable parasites. Spears and Geruso thus spend much of their time showing that human beings can generate new ideas and do useful things. Yes, a person represents another mouth to feed, but he or she also represents another set of hands who can produce food or anything else.

This means that humanity can clean up their messes, come up with systems that better support women and minorities, and find better ways to extract and use natural resources.

It follows that without these extra people, many innovations would never materialize, social progress would likely stagnate or go backward, and there would be too few workers to support today’s high standard of living. To illustrate how bad conditions could become, the writers bring up the fact that “small towns hardly ever have a great Ethiopian place and a great Indian place and a great Korean place. But big cities often do.”

If the prospect of ghost towns, lonely elderly people dying in squalor, and a full-scale devolution into a pre-industrial age fails to raise any alarms, then maybe the loss of one’s favorite greasy spoon will do it.

Values without roots

Although Dean and Geruso carefully avoid moral questions throughout the book — it's taken for granted that abortion is good, modern feminism has zero downsides, and human-caused climate change is a critical matter — they make their one moral claim in favor of having children in the most generic tautology they can muster: “More good is better.”

In other words, a bigger overall population means a bigger number of worthwhile lives. But what makes a life worthwhile? True to utilitarian philosophy, it's all about material comforts and basic necessities.

For those who argue that this makes an insufficient distinction about the moral worth (or worthlessness) of each life and the surrounding context in which a life is lived, they will have to settle for the writers’ quantifications and graphs.

Once Spears and Geruso establish that people are good and that depopulation is bad, they move on to possible solutions. Unfortunately, nothing seems to work. Compelling people to have children (as Romania did under Nicolae Ceausescu) or offering money and additional maternity leave (as the Swedish government has done) have done little to fix the sliding birth rates.

The main problem seems to be that women will have fewer children if the opportunity costs of parenting are too high. As the writers declare in their inimitable prosaic style, “Spending time on parenting means giving up something. Because the world has improved around us, that ‘something’ is better than it used to be.” When men and women find fulfillment in their careers and self-indulgence, they have less interest in sacrificing this for the sake of having children.

While this assertion aligns with their value-neutral utilitarian premises, Spears and Caruso are completely uninterested in countries that still have high birth rates, like those in sub-Saharan Africa.

'Change needs vision and values and commitments before detailed plans matter at all.'

Would it offend their readers to suggest that these countries have high birth rates because there are relatively few opportunity costs that exist because these countries are less developed? Is there something to be said about traditional gender roles and the high regard given to parenthood and children in these cultures? What about the religious practices of these places?

For unspecified reasons, these obvious questions about population trends are scrupulously ignored.

Where science fails

Instead, the writers insist that there is no solution to the depopulation bomb set to go off after the spike: “No one has such a solution. The challenge is still too new.” For the time being, people need to be made aware of the difficulties that await them and consider ways they can organize and effect change.

In other words, it’s a weak ending to a weak argument in favor of a weak position. But even this could be forgiven if the book overall were interesting, but it isn’t. By avoiding moral questions, ignoring cultural factors, and rejecting all speculation, "After the Spike" is boring, basic, and dry.

Still, Spears and Geruso perform an important service by demonstrating the limits of pro-natalism. While it's perfectly reasonable to be worried about the global birth dearth and to try to use the scientific method to fix this problem, the formation of families and communities is a fundamentally human matter that largely transcends the scope of the sciences.

Although graphs can illustrate the superficial reality of declining populations, it will take the humanities disciplines to understand and effectively address this reality on a deeper level. Moreover, it will require letting go of progressive priorities and returning to certain beliefs and practices that made parenthood in the past more appealing than it is now.

This may be hard pill for pro-natalists to swallow, but as Spears and Geruso themselves conclude, “Change needs vision and values and commitments before detailed plans matter at all.”

This "vision and values” just happen to be pro-life — not pro-natalist.