Note: I first started working on this post long before the news about the likely reversal of Roe vs. Wade came out. It doesn’t really have much to do with abortion in my eyes, but you are welcome to cite it if you encounter anti-abortion agitators who are concerned about underpopulation.
I’ve recently noticed a fair number of people expressing concern about the falling birthrate in many (usually rich and well-developed) countries, and the fact that the global birthrate is expected to fall below replacement level near the end of this century (https://population.un.org/wpp/Graphs/Probabilistic/FERT/TOT/900).
It’s clear why this is concerning on first glance — if the birthrate falls below replacement level, and doesn’t ever recover, the human population will eventually shrink to zero. However, it will be a long time before that happens (as in many lifetimes long), the societal implications of an aging population can be mitigated through technological means, and there’s really nothing wrong with having a smaller population anyway. In fact, a smaller population may greatly increase quality of life for the people living in that era.
Let’s dive into why…
Fewer people means each person gets a bigger share of the pie.
This probably goes without saying, but if there are fewer humans competing for limited resources, each person’s “fair share” of the available resource pool will be larger. Now, we all know that resource allocation is rarely fair, but in this situation, humans alive at that time could at least strive towards a society that allocated more resources to each person, as compared to our time, in which residents of rich regions might have to accept a lower standard of living in order to increase fairness worldwide.
Furthermore, while the population is gradually falling, each successive generation will look forward to an even larger share of the pie than what their parents had — something that should make any parent happy. People’s standards of living will rise, and there will be room for them and their projects to grow, without having to worry about exhausting the carrying capacity of the planet. The world still wouldn’t be infinite, but there would be much more breathing room for that smaller population.
And of course, once we become a multiplanet species, this trend will become even more pronounced. There may be a generation in the future in which each person or family gets their own planet — space is big, and humans need not fill it if they don’t want to (more on that later).
Elder care can be managed by robots
One reason why a declining population can be such a big problem for a nation today is that it requires a disproportionate percentage of the working-age population to care for or otherwise support the elderly. In the past, and even in the present, this is still an issue, since most manual labor jobs requiring dexterity and thinking on one’s feet are still performed by humans — and the number of elderly only continues to grow, as people live longer.
However, robotics has made great strides in the past couple of decades, and there is no reason to assume that it won’t progress even further in coming years. Soon enough, elderly and/or disabled people will likely be able to have their assistance needs met by machines — in the same way that i.e. wheelchairs mean that a person who can’t walk no longer needs to be carried from place to place, various robots will gradually take over the roles of modern-day carers. In the very short term, before robots can handle the majority of the tasks required, the shortfall of carers can be alleviated by encouraging immigration from countries with younger populations to those with demographics that skew older.
The elderly, like almost everybody else, also have social needs, but there’s no reason why those need to be filled by younger people. Most people tend to make friends with people around their own age, so most elderly people will probably prefer this arrangement anyway — and I strongly suspect that for many, not needing a stranger around to provide physical and mental assistence will eliminate some of the potential for embarrassment caused by needing assistence in the first place.
We’re not going extinct anytime soon
There are currently 8 billion people in the world. Even if the human population were to halve every century, it would still take around 3000 years for us to die out entirely. That’s more than enough time for people to decide they want more children, or to increase their lifespans so that the population remains stable for much longer of its own accord, or even to develop technology beyond our wildest imagination that would allow them to evolve into something incomprehensible to those of us alive today and render the entire question moot.
This isn’t to say that population growth or decrease shouldn’t be a topic of interest when doing very long term planning, but there is more than enough time to make those plans. We could take generations to make those plans, and our ability to fulfill them would not be appreciably affected by population shrinkage. When humans truly want to reproduce quickly and trigger a population boom, they are more than capable of doing so very rapidly.
We don’t have to fill the universe
The Universe is perfectly content to exist either with or without us, and we should not feel obligated to fill it just for the sake of filling it. Instead, we should explore and settle the Universe in ways that make existing humans happy — which may include having either more or less children, depending on the individuals involved. Remember that ultimately, everything that humanity does should be done for concrete reasons that support concrete ends and improve the lives of real individuals (human or otherwise), rather than in service of cold, abstract principles that may no longer fulfill the purposes they were created for.
And even with a declining population, there will still be billions of us for many years to come — more than enough to fill cities throughout the solar system, if that’s what those people decide to do. If those space city builders desire large families and bustling metropoles, but can’t find enough takers on Earth, they are perfectly capable of having children of their own. Don’t worry about there not being enough people for Mars — Martians will have kids if they want them.
The falling birthrate isn’t being legally mandated
Which brings us to another point: nobody is forbidding you from having kids! While I am in no way qualified to go into detail on all of the causes of the drop in birthrate in developed countries, it is most definitely not caused by a China-style “One Child Policy” or similar government intervention. Although there are many people who want children and can’t have them for medical, financial, or other reasons, the main driving force behind the falling birthrate in rich countries is the simple fact that most people only want one or two kids, and many people don’t want kids at all.
And that’s okay! Having a small family, or choosing to remain childless, is entirely okay. Forcing a person to have children they don’t want is widely considered a serious form of abuse, and should not be done. Nobody should ever be punished for not reproducing, and there is absolutely no moral requirement to have children.
And we don’t really know what’s coming!
We simply can’t see far enough into the future to predict what the population trends of a thousand years from now will look like. We have an idea of what 20th and 21st century living in rich countries, and at various income levels in rich countries, does to the birthrate, but we have no idea what new technological or social developments will come along in future centuries to upend the entire paradigm, just as the industrial revolution and urbanization upended so many existing paradigms in the last couple of centuries and got us to where we are today. We can speculate, but that’s often no better than shear guesswork.
All in all, there is no need to worry about a falling birth rate. While it will certainly lead to some social changes, not all changes are bad, and this one may actually be good for quite a few people. There is no moral imperative to create more people than would naturally come to be — instead, we should focus on doing what we can to make the lives of existing people as good as possible. And if we discover at some point that we genuinely need a larger population, humans are very good at reproducing. Really, a falling average birthrate should be a cause for celebration — we have very little to lose, and a lot to gain.