Birth rates are falling much faster than many dominant narratives imply. The global fertility rate for all of Latin America and the Caribbean fell below the replacement rate of 2.1 babies per woman in 2019. India will achieve that status in 2024. China is expected to be at half its current population by 2066. First-generation immigrants to the US fell below the replacement rate in 2019. Already, 115 countries representing about half the world’s population are beneath replacement, and by the end of the century nearly every country in Africa is projected to have a rapidly declining population.

Even strict religious fundamentalism does not protect against this drop. From the 1980s to the 2010s, the average Iranian woman shifted from having 6.5 to just 2.5 children, and as of 2021 it was 1.6. This drop in fertility beat China’s one-child policy. In the U.S., meanwhile, the Mormon population in Utah fell to almost below replacement in 2021. This is not a “canary in the coal mine” moment. We’ve reached the metaphorical point at which the miners’ skin is sloughing off—all while many claim this dramatic drop is a “minor inconvenience” or even a welcome development.

People underestimate how quickly this effect will be felt. South Korea currently has a total fertility rate of 0.81. For every 100 South Korean great-grandparents, there will be 6.6 great-grandkids. At the 0.7 fertility rate predicted in South Korea by 2024, that amounts to 4.3 great-grandkids. It’s as if we knew a disease would kill 94 percent of South Koreans in the next century.

People underrate how quickly this can become serious, once it is felt. As recently as the mid-1990s, South Korea had a birth rate of 1.7, which is close to the U.S.’s present rate. A fertility collapse takes around thirty years before it causes a population collapse, and once that happens, the collapse is inevitable. If 70 percent of a nation’s population is over age 50, and even though many of those people have almost half their lifespan left they are not going to be having any more kids.

Across the world, we see a similar phenomenon: countries explode in population as access to modern wealth expands, then drop off and begin to collapse as incomes rise and lifestyle modernization sets in. While many countries have yet to reach this crescendo, most are well on their way. But why is this happening?

Consider your personal social group. If you are like most in the developed world, around a third of your peers will have no kids and about a third will have two kids. If that group is to hover just above the repopulation rate, the final third must have over four kids each.

People misframe the question of stable birth rates when they ask “Why is everyone in my community not having two kids?” We already know that in the modern world, broken matchmaking and individual choice will drive a large portion of people to forego parenthood entirely. As such, if fertility in your community is to stay sustainable, it is up to a certain number of those who do have kids to have quite a few kids. Modern societies should not be asking: “Why isn’t everyone having kids?” but rather: “Why aren’t many in my community having five to seven kids?”

When the question is reframed, the answer is still obvious, but subtle in its implications. Purely hedonic returns from having more kids diminish significantly after two kids. Even when the financial constraints associated with child-rearing are completely lifted, there are only three reasons a person has well over two kids: if every child they have adds significantly to the family’s economic prospects; if the family lacks the education necessary to use birth control effectively or is in a situation where birth control is not an option; or if there is some cultural externality motivating them to have lots of kids.

While economic gain has historically been a driver of high birth rates, the global decline in child labor and household businesses with modernization has removed this factor. Lack of access to birth control is also increasingly no longer a factor with a massive worldwide increase in female education, sex education, and birth control availability. This is favorable news in many ways, but it also means this future of widespread prosperity, female education, and modernization is inherently unstable unless prosperous egalitarian societies can maintain or increase their populations through sustainable birth rates.

Many people have the intuition that when a population crashes, the amount of resources left to go around will increase on a per-person basis and this boost in individual prosperity will create a new homeostasis at which populations reach a sustainable, more-or-less constant level, or even start to grow. This intuition is wrong on three fronts. 

First, we have seen what happens to nations later on the “fertility collapse timeline” than ours like South Korea. Decline has not tapered off in any of the later-stage demographic collapse nations. If there is an organic floor on fertility collapse, it is so low as to be irrelevant.

Second, increasing individual wealth is associated with decreases in birth rate. While birth rates eventually recover at extreme levels of wealth, they only hit above-repopulation levels when a family is earning between $500,000 to $1 million dollars a year. In the same way that the birth rate begins to crash around an income of $5,000 a year, presumably correlated with an individual’s participation in the modern economy, something similar is happening at the $500,000 mark. Around $500,000 a year may be the income level at which the average person is no longer compelled to be involved in the modern pattern of labor mobilization; they don’t have to work or can at least work flexibly. But this is a relative effect, not absolute, so rising resources overall won’t help.

Third, given how much we have leveraged our land, companies, cities, states, and nations, decreasing populations may even dramatically reduce wealth and trigger a cascade of defaults. We saw this situation play out in Detroit, which lost 40 percent of its population over the last 60 years. Even if people can buy a house for a thousand dollars when the population collapses, those houses will have partially caved-in roofs, be stripped of wiring, and be devoid of power and running water. Our entire civilization has been built like a Ponzi scheme that requires constant growth. That scheme will eventually collapse.

In fact, an infrastructure collapse is a near constant of any location that has a dropping population. The way we have laid out roads, power, or water infrastructure, for example, is not easily partitioned. If you build out infrastructure in a city to deliver water to a million people and its population drops to half a million, it still costs almost as much to maintain as it did before, with half the tax base and half the benefit.

False Solutions

Some imagine that AI or some other technological breakthrough can act as a deus ex machina to ameliorate the economic challenges of population decline by substituting for human workers in the economy. But even in the optimistic case this will not solve all of it, and it may cause its own very serious problems. At the very least, AI will only help the supply side of the incoming economic disaster because it does not consume in the same way humans do. AI wealth may not help at all with infrastructural maintenance, or may even cause it to be even more neglected as it removes the economic imperative to solve coordination problems faced by human workers. 

The fallout from demographic collapse extends beyond crumbling infrastructure, failed pension funds, unstable governments, and faltering financial markets. Consider that almost everything about the human sociological profile has a genetic component, ranging from prosociality to altruism and voting patterns.

Our economy is structured in a manner that organically identifies and maximally utilizes talent to create short-term marginal productivity. The system differentially sorts for the most potentially productive among us, and then offers them money and status to forgo other life activities that don’t create immediate productivity.

There is little that draws a person away from immediate economic productivity more than a social lifestyle compatible with good matchmaking, strong family ties, and child rearing. No one gets financially rewarded in our current system by structuring cities in a way that invites the creation of large families. In fact, many will be punished if this pressure exists by local companies having less worker time, for example. For this reason, the centers of productivity in a modernized economy will intrinsically be suboptimal environments for raising large families.

Those who propose to “solve demographic collapse with immigration” are implicitly endorsing the creation of a toxic situation where the developed world’s economy is reliant on Africa staying poor. This is because if high-birth-rate nations are allowed to continue on their path to development, they, too, will fall below the repopulation rate. Worse still, because the system we have built differentially feasts on the most productive and prosocial people and culturally castrates them, it unsustainably consumes human capital.

If you differentially kill friendly elephants with large tusks, the remaining elephants will have smaller tusks and exhibit more aggressive behavior. The same is true for humans. The sociological profile most amenable to what we think of as modern cosmopolitan society—one that is open-minded, pluralistic, technophilic, and egalitarian—is being aggressively deleted from the world’s population. Given the differential birth rates and the heritability of certain traits, we may see a standard deviation shift in political attitudes towards theocratic dictatorialism within the next 75 years or so.

Cultures That Last

The demographic problem seems very dark, but there is a silver lining that comes down to the final reason people have more than two kids: The presence of a cultural motivator.

Suppose we manage to build a culture that is pronatalist, technophilic, productive, and pluralistic but immune to the siren call of the talent beast. Suppose we, the authors, have eight kids and each of them has eight kids, for example. If this could be kept up for eleven generations, we would have more descendants than people currently alive on Earth and would have set the tone for the future of human civilization. This example is perhaps unrealistic and even undesirable, but it illustrates that a relatively small seed can have a big effect.

Cultural mass extinction is avoidable if just a handful of families from each culture manage to make their cultures intergenerationally durable. Their cultures would be made durable in the sense that they have children above the repopulation rate, and they raise these children in a way that convinces enough of them to also have many children, and so on.

But a future populated only by the descendants of very few family cultures is a failure scenario, as it would be an incredibly homogeneous world prone to fragility. The ideal is a future in which as many cultures as possible—both old and new—cooperate and compete in a diverse cultural ecosystem, sharpening each other in the process.

Part of the reason many are averse to thinking about these problems is that they are associated with the high-modernist approach of twentieth-century eugenics, which targeted centrally determined “desirable” and “undesirable” traits. A focus on creating a diversity of sustainable cultures is a very different proposition and doesn’t share the same failure modes. The key problem is not controlling fertility and diversity, but making room for it and allowing it, which both the current modern system and twentieth-century eugenics do not.

Noticing that genetic traits affect behavior isn’t the problem. The problem is allowing centralized systems to try to control and optimize genetic outcomes, which could only lead to homogenization and centralized pathology. What’s needed is the opposite of centralized valuation—an expansion of choice at the family level that supports a diversity of cultures, desirable societies, and the people that will live in them.

Ensuring the future of our species is dramatically easier than one might imagine. We live in a world in which technophilic cultures are being aggressively deleted, and in which the most productive and meritocratic people are being functionally castrated. This means that even a small group of technophilic, meritocratic families with high birth rates can become the new norm within a few generations. The key challenge for these new cultures will be to maintain their social defenses against the alluring pathologies of the failing modern social system.

But the great thing about living in a world of dying systems is that you are uniquely well-positioned to replace suboptimal systems with something superior. New growth takes root best in the decay of its predecessors. For most of the past, if you wanted to create a better future, you had to rally the troops and take someone else’s land or destroy existing systems and replace them. In a dying world, all you have to do is create something intergenerationally durable.

A century ago, Japan launched a brutal war in hopes that its culture and people would come to dominate China and Korea. Given that all three countries currently have collapsing populations, any of the three could easily dominate their region in just a few generations if they could merely motivate a high or even just stable birth rate within some segment of their population. Given that for every hundred South Koreans there will be 4.3 great-grandchildren at their 0.7 fertility rate, this is very doable. Low-fertility-rate nations will have a very hard time holding up against any culturally sustainable neighbors after a 95 percent population collapse.

Humanity can be thought of as an evolving hardware in the form of our biology and genetically coded predilections, and an evolving software in the form of our religion and culture. Historically speaking, conversions are fairly rare, so most religions and cultures survived by helping their hosts survive and reproduce.

We spent the last century or so ripping this cultural lattice from our psyche and replacing it with the jury-rigged modern economic culture. These systems we ripped out were not an afterthought; humanity co-evolved with them. Should we be so shocked that birth rates plummeted and mental health problems skyrocketed when we ripped out a component our brains evolved to work with? Should we be so surprised that as cultural orphans with faded cultural memory, we search for meaning in the half-baked ideologies of Goop, Effective Altruism, and other modern guru-spheres?

We don’t need to tread the exact steps of our ancestors to get back to a sustainable culture. Little of what came before is compatible with an industrially advanced civilization, nor did it prove itself able to hold up against the pathologies of modern culture. We also don’t need to wait for someone to tell us what is true. The terrifying and exciting nature of the times is that each of us has the chance to define the future of our species through the cultures we create for our families, stitching together modern philosophy, the remaining shreds of past traditions, and our own innovations.

Mainstream culture does not work: it does not motivate sustainable birth rates. In order to make the leap to a culture that does, many of us must create new cultures or significantly fortify those we inherited. Those who will throw their chips in with this massive cultural and demographic experiment by consciously creating a family, and then raising it in an intergenerationally durable culture, will shape the future of our species. Is this an easy feat? No. But what makes this endeavor so appealing and hopeful is that it is within nearly everyone’s reach, so long as they’re willing to try. The future belongs to those who show up.