The Fermi Paradox and the Birth Dearth

I've mentioned the Fermi Paradox a number of times which asks the question: "where are the aliens?" The story goes:

    During a 1950 visit to the Los Alamos National Laboratory in New Mexico, Fermi and some colleagues were discussing extraterrestrials and interstellar travel over lunch, in conjunction with a cartoon from “The New Yorker” showing aliens stealing New York City trash cans.

    As the story goes, Fermi famously asked, “where is everybody?” Three people who were part of the discussion later reported that Fermi was specifically talking about interstellar travel: If aliens exist and are capable of flying between the stars, then they should have visited us already.

    Fermi never published any work on his off-the-cuff remark, and died just four years later. However, his question lived on and became known as the Fermi paradox.

Given the number of stars and planets in the galaxy, even a very low probability of intelligent life forming must still yield a large number of potentially spacefaring species in the galaxy over its lifetime that should have been able to spread throughout the entire galaxy by this time, discovering our planet in the process. At a minimum, we should have been able to detect some signal or other sign of advanced technological species. But we haven't, according to mainstream science. (There is evidence to the contrary: the mysterious Wow Signal, the oddities concerning Tabby's Star, the strange acceleration of the Oumuamua "comet", the UFO footage and information released by the Navy indicating craft way beyond anything our technology can create, and more).

    So where are they? The answer generally posited is that there must be some sort of "great filter" that prevents intelligent species from maintaining an advanced technological civilization. There are a great number of hypotheses as to what might be the Great Filter and the YouTuber, Isaac Arthur, has created numerous videos exploring these different hypotheses. Common ones are war, exhaustion of resources, or perhaps something sentient that simply wipes out such civilizations after they arise. 

    Glenn Reynolds, looking about our world, suggests something more mundane: depopulation as a consequence of people simply choosing not to reproduce. In his piece, "Free Will, Children, and the Great Filter," he observes:

    One of the things about pretty much all human societies until recently is that they put pressure on their members to have children.  Some of that pressure was provided by nature in the form of hormones and sex drive, but some of it also came from societal/cultural pressures to reproduce.  Get rid of those and people have fewer kids. 

    One example is China, where rates of marriage and childbirth are plummeting, far below replacement.  As the New York Times recently reported, even backing away from the one-child policy hasn’t changed things.  Chinese of 50 years ago wanted lots of kids.  Chinese today, on the other hand, don’t care so much.  The cultural chain has been broken, and it won’t restart itself just because the Party realizes it made a big mistake.  People got used to smaller families, and to lifestyles that make bigger families harder and more expensive.

    Add to that the social and financial uncertainties created by dictatorial government, and, well, no children please, we’re Chinese...

Of course, if you've followed my blog for very long, you already know that it is not just China, but the whole world facing declining populations. Reynolds continues in this vein:

    Tough luck for the Chinese, we might say smugly, but it serves them right.  Er, except that something more or less like that is happening pretty much everywhere.  Birth rates are way down everywhere – even in sub-Saharan Africa, though the trend there started later and has further to go – and we can’t blame that on the one-child policy.

    In Japan and South Korea, which never had the one-child policy, birth rates are frighteningly small.  South Korea has the world’s lowest birth rate:  “The country’s fertility rate, which indicates the average number of children a woman will have in her lifetime, sunk to 0.81 in 2021 – 0.03% lower than the previous year, according to government-run Statistics Korea.  To put that into perspective, the 2021 fertility rate was 1.6 in the United States and 1.3 in Japan, which also saw its lowest rate on record last year. . . .  To maintain a stable population, countries need a fertility rate of 2.1 – anything above that indicates population growth.  South Korea’s birth rate has been dropping since 2015, and in 2020 the country recorded more deaths than births for the first time – meaning the number of inhabitants shrank, in what’s called a ‘population death cross.’”

    It's all part of what Brink Lindsey calls a “global fertility collapse.”  He calls it that because that’s what it is.  “The defusing of the population bomb was a triumph of capitalist wealth creation — but it came with a catch. Birth rates fell enough to avert Malthusian catastrophe, but then they kept right on falling. In the 1970s, sub-replacement fertility rates — that is, rates below the roughly 2.1 children per woman needed to maintain a stable population — began cropping up in rich democracies. But low fertility didn’t confine itself to rich countries; it kept spreading. As of now, roughly half the world’s population resides in countries with sub-replacement fertility.”

    There have been government policy decisions that have contributed. Reynolds mentions, as an example, car seat laws for children which prevented 57 fatalities nationwide in 2017, but simultaneously "led to a permanent reduction of approximately 8,000 births in the same year, and 145,000 fewer births since 1980, with 90% of this decline being since 2000." But, he continues, "the real reason people are having fewer children is because they want fewer children." As he notes, children are expensive and require a lot of hard work and time. And government subsidies won't work because they are too little: they don't come close to compensating for the cost of children or replacing other things like career development, being able to afford vacations, or sleep in on weekends. 

    Reynolds also notes that children no longer bring financial and social upsides they did in the past. He isn't discussing child labor (although that is a factor). Rather, he observes that having a family (i.e., getting married and having children) carried a certain cachet: it was a mark of finally achieving adulthood and being viewed by employers as more stable and responsible. 

    I would further argue that the costs of children have become so prohibitive that children have, in effect, become luxury goods that are increasingly unaffordable to the middle and working class. Karen Guzzo, Professor of Sociology and Director for Family & Demographic Research at Bowling Green State University, likened having children to being a privilege, stating: "It's almost like the haves and have-nots in terms of who gets to have children, because it's so expensive." Having children means having to buy or rent a larger house, a larger car, additional household expenses, and so on. A 2017 NBC article relates: 

    The average middle-income married couple spent between $12,350 and $13,900 on each of their children in 2015, reports the U.S. Department of Agriculture. Extrapolate from that number and you’re looking at spending $233,610 per child from birth through age 17.

    Higher-income families can expect to spend significantly more, around $372,210, while the data shows that lower-income families spend close to $174,690.

And that is the cost per child not including college based on old data. I'm also not sure if it includes costs of childcare expenses. A survey of parents conducted this year (2023) found that, on average, 27% of their household income on child care expenses, with 59% of parents surveyed planning to spend more than $18,000 per child on child care in 2023. If you have a child with a disability, the costs are greatly multiplied both in terms of financial expense and the time and effort that must be expended. 

    Sadly, many potential parents would have children if it cost less to do so. A Newsweek poll from earlier this year (2023) found that "[f]or members of Generation Z between the ages of 18-24, 53 percent said that they would consider having children if the cost of living were lower. Similarly, of Millennials aged 25-34, 55 percent said a lower cost of living would make them think seriously about having children."

    But back to the issue of the Great Filter, Reynolds notes that while not getting married or having children might be financially sound on an individual basis, it has significant downsides in the aggregate: 

    On an individual level, of course, it’s great that people are free to have fewer children, or no children, if they want.  As Elton John informs us, if you choose to, you can live your life alone.  But at a societal level, declining birth rates pose a lot of problems.  First of all, they’re fatal to the Ponzi schemes that comprise most retirement and pension plans.  And even without Ponzi schemes, retirees can only claim a share of whatever wealth is available in general when they retire.  Individuals can save for retirement, but societies really can’t, since even stored-up wealth is just a claim on the productive capacity available when people (or maybe I should say generational cohorts) hit retirement.  If the population is smaller, there will be less wealth available, probably, and at any rate the retirement costs will be spread over a smaller group, meaning that the remaining individuals will feel the pinch more.

    Societies laboring under “population death cross” are also likely to be less dynamic.  Older people aren’t as hidebound as popular culture would have it – most successful entrepreneurs are well into middle age, and some are downright old – but there’s still a measure of truth to that idea.  And fewer people just means fewer sources of ideas, innovation, and energy.

    Anyway, it’s at least conceivable that wealthy, technologically advanced societies in general hit a death spiral:  Fewer people, less dynamism, fewer children, etc.

    Alternatively, more traditional cultures will gradually replace everyone else simply by continuing to breed.  (In American history, the Shakers died out, the Mormons flourished).  Perhaps in a few generations the world will be disproportionately composed of Amish, Mennonites, Orthodox Jews, fundamentalist Muslims, traditionalist Catholics, and the like.

    Such a world might get along fine, at least from the perspective of its inhabitants, but be less disposed to interstellar travel, which suggests that the great filter may not actually be fatal to a species, just to its capacity to be noticed by others.