The Paradox of Low Fertility

Modernity has a strange paradox. During a time of great abundance, when most children live to adulthood, fertility has fallen well below replacement.

Abundance normally causes population growth. After a forest fire, light-loving plants have a population explosion, because light is abundant. On a fresh plate of agar jelly, bacteria multiply rapidly. When it rains in the desert, flowers bloom. If you feed the geese in the local park, their numbers increase. Nature abhors an under-utilized resource. Abundance causes populations to increase until scarcity returns. That feedback loop controls populations.

Abundance causes population growth, because organisms are reproducing machines. Their forms were selected to have the effect of reproduction. All types of life have the capacity to increase in number, by excess (above-replacement) reproduction. Populations are limited by premature death, not by voluntary low fertility. Given abundant resources, every type of life reproduces to excess.

Except, apparently, human beings in modern civilization.

In recent history, humans did reproduce to excess. The human population exploded during the last few hundred years, especially during the 20th century. The population explosion was due to modern civilization, which reduced childhood mortality. For most of human history, the population was controlled by war, disease and famine. Modern civilization reduced those causes of premature death. Today, most children live to adulthood, even in developing countries. So, the human population exploded. It is still growing today, by roughly 80 million people per year.

See The Demographic Tsunami for an overview of how the world’s population is changing.

However, this growth is not as explosive as it could be. Given abundant resources, populations normally grow exponentially. The human population has been growing linearly, not exponentially, for half a century. It increases by roughly the same amount every decade, not by the same percentage. This is due to declining fertility, not increasing childhood mortality.

The low fertility is voluntary. People are choosing not to reproduce, especially in the more developed (modern) parts of the world.

It is a paradox that a reproducing machine, whose form was selected to reproduce, would choose not to reproduce.

This doesn’t happen with any other species. No species lowers its fertility in a time of abundance. It didn’t happen to humans in the past. It is a recent change in human behavior.

Why are people choosing not to reproduce?

In talking about human nature, the first task is to create a detached, scientific frame. Most people default to a moral frame when thinking about human beings. So, if you ask the question “Why has fertility declined?”, they might respond with “Low fertility is good”, “It’s not a problem” or some other non sequitur. In fact, people often become uneasy or agitated if you discuss human nature from a detached, scientific perspective. But that’s what I’m going to do.

To understand human behavior, we must understand psychology and biology. Human behavior has causes, and we can understand those causes. Again, this makes some people uncomfortable, but that’s what I’m going to do: explain human behavior in terms of psychological and biological causes.

Low fertility has become a morally charged topic. Most of the discourse around it begins with a value judgment: whether low fertility is good or bad. This prevents understanding. It activates a frame of advocacy rather than inquiry.

Conservatives and reactionaries (those on the “right”, loosely speaking) tend to view low fertility as bad. They believe that it is caused by the breakdown of traditional values, which (in turn) was caused by progressive/liberal ideology and social control. So, they believe that low fertility is caused by deception or coercion. They blame the left for this change in human values. They believe that restoring traditional values would restore fertility.

Progressives and liberals (those on the “left”, loosely speaking) tend to view low fertility as good or neutral. They believe that it is due to increased knowledge and agency. Some believe that low fertility is a natural mechanism for avoiding overpopulation. They believe that humanity is going through a “demographic transition” from high fertility and high childhood mortality to low fertility and low childhood mortality. They view this transition as progress, which benefits individuals and humanity as a whole.

Both views are incorrect. Both sides are blind to certain aspects of the issue.

Let’s debunk the right-wing view first. Low fertility was not imposed on people by the left. It is not primarily due to the breakdown of traditional values and their replacement by new, modern values.

First, high fertility was not caused by traditional values, so its decline is not explained by the breakdown of traditional values. What we call “high fertility” today is just the natural level of fertility. Women have the ability to give birth to 10 or more children. Without birth control, most women would have at least 5 children. Fertility above 5 children per woman was the norm in premodern societies. The population was controlled by premature death, not by low fertility.

Traditional religion and morality did not promote fertility. The main focus of traditional sexual morality was preventing sex outside marriage, not promoting reproduction. Low fertility was not viewed as personally or morally bad. The Catholic church had celibate priests and nuns. Christianity focused on the inner self and the afterlife, not on biological success in the material world.

There hasn’t been much antinatalist propaganda in mass media or education. During the 1970s to the 1990s, most popular entertainment was family-oriented, and portrayed a rosy view of family life. There were many TV shows about happy families, such as The Brady Bunch and The Cosby Show. Love between a man and woman was also a common theme. In general, the media promoted men and women falling in love and having children.

Popular culture did promote an extended adolescence and casual sex, but that was mostly bottom-up. As people shifted toward a lower-fertility lifestyle, the media increasingly showed and celebrated that lifestyle.

It’s also true that young women have been encouraged to pursue careers instead of becoming homemakers. The education system, more so than mass media, promoted that value. However, that change also seems to have been mostly bottom-up, not top-down. Given more options, women are choosing to prioritize their careers over having children.

The media has effects on culture, and thus on human behavior, but culture primarily depends on human nature. Entertainment and advertising must appeal to human emotions. The media couldn’t “sell” us low fertility if it wasn’t intuitively appealing.

Also, the collapse of fertility is not confined to the West. Places as culturally different as South Korea and Iran have below-replacement fertility. The formerly communist countries of Eastern Europe have very low fertility, despite having a more “based” culture (probably due to less Western media consumption). Low fertility seems to be an effect of modern civilization in general, not specifically the current culture of the West.

Some on the right will complain that mass immigration, high house prices, and other social conditions have negative effects on family formation and fertility. That may be true to some extent, but our ancestors had plenty of children while living in small huts, tents, or caves, while struggling to feed themselves, fending off predators, etc. It could be argued that expectations have been set very high, so people are not comfortable having children in the current environment. But there are subpopulations within modern societies that maintain high fertility, such as the ultra-orthodox Jews, fundamentalist Muslims, Amish, etc. If a couple really want to have children, they can have children. If a single woman wants to have children, she can have children.

Again, low fertility is not confined to the West. It occurs in many different countries with different social conditions, such as China, Japan, Russia, Germany, Brazil and Iran.

Now, let’s debunk the left-wing view. It is partly correct. Low fertility is due to increased agency, not deception or coercion. However, it is not due to an innate mechanism for avoiding overpopulation, and we are not going through a demographic transition to a new mode of existence. Low fertility is not part of a march of progress toward a more rational world. It is a breakdown of human nature caused by modern civilization. Voluntary low fertility is not a stable mode of existence. It is evolutionarily unstable.

There is no innate mechanism for avoiding overpopulation. Such a mechanism could not evolve. That belief is based on ignorance of biology and the moralistic fallacy. All types of life are selected to reproduce. Humans have had many local population explosions in the past. We are still in a global population explosion, despite declining fertility.

I presented the case against demographic transition theory in Fertility and Destiny, so I won’t repeat it here.

The collapse of fertility is due to new types of agency, provided by modern civilization.

Birth control is the main cause of low fertility. It allows people to have sex without reproducing. It gives us a new choice — one that our ancestors didn’t have. Our emotions are not adapted to this new form of agency. We didn’t evolve to choose to have children. We evolved to choose to have sex, which had the effect of producing children. Given the ability to control reproduction, most people choose to have fewer children.

There are other contributing factors. Modern civilization liberates women from their economic dependence on men. This has caused a breakdown of the pair-bond. Modern civilization provides alternatives to real life, such as drugs and entertainment. We have cute little pets that replace children. Modern civilization has resulted in a “great replacement” of real life with simulations.

See Alienation and Art.

Low fertility primarily arises from human nature, although of course culture and conformity are involved in its widespread adoption. Low fertility was not imposed on us. It was given to us, by modern technology.

Low fertility is a choice, and a natural consequence of human emotions in the modern environment. But it is not adaptive. Voluntary low fertility is maladaptive. It is a breakdown of the human organism.

Choosing not to reproduce is the biological equivalent of suicide. If you have no children, your life is biologically pointless. So, the choice to have no children is extremely maladaptive — as maladaptive as jumping off a cliff. It is also maladaptive to have few children when you could have more.

It seems paradoxical that human beings are committing biological suicide en masse.

The paradox disappears if you understand (and accept) that human nature is an evolved mechanism, and our values are generated by that mechanism. There is no value oracle in the human brain that always generates adaptive values. Values arise from the emotions, which are heuristic, ad hoc and stimulus-dependent. There is no guarantee that they will generate adaptive values in every environment.

The brain is a mechanism that doesn’t always work, and emotions are the most fragile and kludgy part of that mechanism.

We have various emotions that push and pull us in different directions: hunger, thirst, lust, fear, etc. Each emotion motivates us to solve some biological problem. But no emotion motivates us to reproduce per se. There is no reproduction drive.

In the ancestral environment, human emotions had the combined effect of reproduction. If they didn’t, you wouldn’t be here. But now, they don’t generally have that effect. In this environment, human emotions generate maladaptive values, such as wanting to have no children, or putting career ahead of family. As we go deeper into modernity, our emotions become more and more dysfunctional.

Modern civilization has liberated human nature from its ancestral constraints. Ironically, this has broken human nature.

Leftists and liberals don’t see low fertility as a problem, because they sacralize human nature. They assume that human nature is essentially good, and thus it will produce good outcomes if it is liberated. They become upset if you point out that human behavior has become systematically maladaptive, and that this is not going to produce a utopia.

Conservatives and reactionaries see low fertility as a problem. They believe that it is caused by the imposition of new values, and that it would be fixed by restoring traditional values. They are wrong. Even if we could restore them, traditional values are not adaptive in the modern environment. They cannot solve the problems of modernity.

A new type of agency can break human nature, because it allows us to make maladaptive choices. To make adaptive choices, you need adaptive values. But what if you have the “wrong” values? They wouldn’t seem wrong to you.

That is another paradox of low fertility. It is only a problem for those who don’t see it it as a problem.