In 1950 the physicist Enrico Fermi was dining with three colleagues at the nuclear weapons development facility in Los Alamos, New Mexico, and the conversation turned to extraterrestrial life. The topic had been on the public mind since the supposed crash of a flying saucer near Roswell, N.M., a few years before. As his colleagues later reported, Fermi asked: Where is everybody? Given the billions of planets that might be capable of supporting life, why haven’t emissaries of other advanced civilizations—claims about Roswell notwithstanding—visited Earth? This simple question has since become known as the Fermi Paradox.
In the decades after Fermi posed this question, fascination with interstellar travel and extraterrestrial civilizations gave rise to one of the most popular cultural products of the late twentieth century: Star Trek. The original television series aired from 1966 to 1969, and was followed by numerous spin-off TV series and movies. A key element of the franchise’s appeal was its optimistic portrayal of a future human society answering the Fermi Paradox by discovering many complex civilizations in other parts of the galaxy. Meanwhile, the future human society depicted in Star Trek was both technologically advanced and economically progressive, a post-scarcity welfare state.
But projecting forward the type of human civilization described in Star Trek actually yields a very different future for humanity, and a very different resolution to the Fermi Paradox. If extraterrestrial civilizations follow the current path of our own, no technologically advanced civilization will ever travel among the stars. This is because they will all undergo demographic collapse once they are technologically capable of limiting their reproduction.
Inspired by the Fermi Paradox, in 1961 astronomer Frank Drake proposed an approach to determine whether there were advanced extraterrestrial civilizations out there somewhere. Among other factors, Drake wondered how long a technologically advanced civilization would endure, and whether it would be long enough to facilitate interstellar travel. The sorts of obstacles to the development and survival of advanced civilizations are known as “Great Filters.” Some of these filters are ones humanity has already passed through, such as the unlikelihood of multicellular life arising and surviving in the first place. Others could lie ahead of us, including nuclear armageddon and human-induced environmental collapse.
Regardless of the future likelihood of these threats, neither nuclear nor civilization-ending climate catastrophes have yet arrived. However, we are now facing another Great Filter: massive population decline. And unlike with other possible filters, on this one we have hard data.
“Unlike with other possible filters, on this question we have hard data.”
In discussing demographics, the key number to remember is 2.1. That is the number of children each woman needs to bear on average to maintain a stable population in a developed economy. The one tenth extra is to compensate for women who are infertile or women or children who die before they can reproduce. Despite great strides in reducing infant and maternal mortality, that number may be 2.3 or higher in poorer areas. This replacement fertility rate is an aggregate average. This means that for every childless woman, another woman must have four or more children to maintain a stable population.
In the “baby boom” years of the 1950s and 1960s, the world fertility rate was just under five. By 2020, it had fallen to just over two. UN population figures, which are widely relied on in demographics, assume that this continuous decades long decline in fertility will soon flatten out. However, this is based on outdated observations that fertility improved when the economy did. Not only does this assume that economic conditions will improve, but more recent research has shown that the correlation between prosperity and fertility no longer exists.
While they continue to work with current UN numbers, most demographers now dismiss its projections because they do not adequately account for the continuing decline in fertility rates, implausibly assuming that this trend, driven by deeply entrenched and continuing global phenomena such as increasing education and employment of women and rapid urbanization, will suddenly and inexplicably stop.
The global rate obscures wide discrepancies in fertility rates across regions. Higher than replacement rates are largely found in sub-Saharan Africa and central Asia, but most of the rest of the world is already below 2.1. The US fertility rate is 1.6, and Europe’s is 1.4, with many European nations declaring population collapse to be a national emergency. These include Italy (1.2), Spain (1.2), Poland (1.3) and Greece (1.3). Perhaps best known are already ongoing population declines of East Asian countries such as Japan (1.2), China (1.0), and South Korea (0.72).
It isn’t just a matter of raw total numbers, but the distribution of those numbers among age groups. Historically, healthy human populations looked like a pyramid, with a base of young people, a substantial middle of working age adults and a small top of elderly. Below-replacement fertility rates invert this pyramid. The base of young people gets smaller, funneling fewer working adults up the pyramid until the middle also decreases while the top grows ever larger thanks to extended life expectancy. This puts significant economic stress on modern welfare states with generous pensions and other support for the elderly, as there are ever fewer working adults to pay the taxes to supply these transfer payments. For example, in 1960 Japan had about seven workers for every retiree, whereas now there are only two workers per retiree. And this ratio continues to decline, not only in Japan but in every other nation with below-replacement fertility. Funding these transfer payments underlies exploding national debt levels across the world.
These debt loads will be continuously exacerbated by falling population levels. Young people are the most active workers and consumers in the modern economy. As their numbers decline, the economy’s production and consumption decline as well, along with its ability to fund spiraling national debt burdens. And a society without young people is going to be one with very little innovations.
When large amounts of capital are diverted to supporting non-working members of the population, national and private debt levels will continue to soar. Funding for projects which are not of immediate economic value will therefore disappear. One of these unfunded grand projects is space exploration.
When he set out to create his “western in space” in the 1960s, Gene Roddenberry wasn’t planning to engage in an academically rigorous exercise in futurology. He was just trying to create popular entertainment and get good ratings. But from its modest beginnings, Star Trek has become a cultural touchstone that reflects the culture that created it: the politically and socially liberal environment of late twentieth-century California. It is no accident that the central organization of the Star Trek future, Starfleet, is headquartered in San Francisco.
Writer Ryan Britt reports that when President Ronald Reagan visited the set of Star Trek: The Next Generation, actor Patrick Stewart found the courtesy call “as grotesque and bizarre as you can imagine.” Britt notes that “Star Trek actors and writers are mostly against policies that come from the Republican Party,” and cites Rep. Alexandria Ocasio-Cortez as a typical fan of the future portrayed in Star Trek. Kate Mulgrew, the actress who portrayed AOC’s favorite character, Captain Janeway of Star Trek Voyager, reciprocates the lawmaker’s admiration.
The future history elaborated in Star Trek, reflecting as it does the values and aspirations of the leading edge of our civilization, can serve as a template to consider how likely it is that this civilization, the only technological one we know of, can resolve the Fermi Paradox.
Probably without realizing it, the creators of the many Star Trek TV series have provided the necessary data to make population projections to test Star Trek’s proposed solution to the Fermi Paradox. To date there have been a dozen completed TV series based on Star Trek with over 900 episodes, hundreds of hours of usually carefully developed and consistent portrayals of humanity’s possible future. These completed series have featured thirty-four human female main or recurring characters. We focus on main or recurring characters because they are the ones with enough screen time to show their personal backgrounds and circumstances.
Over almost five decades of our time, from the first series in the 1960s to the present (and several centuries of the Star Trek future history), these thirty-four women are portrayed as having borne a total of sixteen children. Using the standard demographic formula, this yields a fertility rate of 0.47 (which we will round to 0.50 for our calculations)—lower even than modern South Korea. To provide a reality check, consider the reproductive history of the thirty-four actresses who portrayed these characters. They do a bit better than the characters they played. To date they have had a total of twenty-four children, for a fertility rate of 0.7, still below present-day South Korea. (California’s current fertility rate is 1.52, among the lowest in the United States.)
What happens when a species’ fertility rate is 0.5, less than a fourth of what is needed to replace its numbers (2.1)? First, we need a starting point. While the current United Nations forecast is that the world’s population will peak at 11 billion sometime late in this century, as noted above, most demographers find that to be an over-count. Organizations such as the Wittgenstein Center for Demographic and Global Human Capital in Austria and the Institute for Health Metric and Evaluation in Seattle have run their own analyses and predict that the peak will be lower and come sooner Demographer and economist Jesús Fernández-Villaverde and his colleagues estimate that the peak population will more likely occur in the 2060s at approximately 9 billion, and then rapidly fall. (The United Nations agrees that after reaching its peak the world’s population will sharply decline, just beginning somewhat later and from a higher maximum.)
Using the 2060s as a peak brings us into alignment with Star Trek’s future history. In that history, the first faster-than-light “warp” drive flight is in 2063, about when Earth will have its maximum population, according to demographers. Star Trek’s creators took a shortcut to bring about this Fermi Paradox-breaking event. Instead of a deus ex machina, we might describe it as a vulcani ex machina. Immediately after the warp drive is first tested by a lone iconoclast (with the help of the starship Enterprise from the future) the Vulcans show up to help humanity begin its slow advance as a space-faring species. (The Vulcans are a species of benign pointy-eared aliens who include the father of one of the most iconic characters, Mr. Spock.)
“Star Trek’s creators took a shortcut to bring about this Fermi Paradox-breaking event.”
Another key feature of the Star Trek future is its vision of a post-scarcity economy. This is based on another near miraculous development: a magical technology that permits, seemingly without the need for any input of material, the replication of any physical object. This magical socialist utopia reflects the attitudes of the Californian progressives who created the lore. As with real socialist societies, there is no independent entrepreneurship, no economic dynamism, no driven iconoclastic creativity in Star Trek’s future society. The aim of scientific and technological advancement largely to counter hostile aliens, and personal ambition is directed to rising in the bureaucracy, not innovation.
Returning to the world of hard data, while many moderns claim that economic hardship is their reason to postpone or forgo having a child, in almost all countries economic growth actually correlates directly with a decline in fertility. Further, generous government financial incentives and benefits such as free childcare intended to ease these supposed economic disincentives to child-bearing have proven ineffective in raising long-term birth rates. Therefore, even if we allow Star Trek its utopian post-scarcity socialist economy, based on demographic facts the society portrayed in this future history would presumably still have the low birth rates shown in the TV shows and movies.
The following chart superimposes the Star Trek future history on projections of human population sizes, assuming that future has the 0.5 fertility rate portrayed in the Star Trek TV series. (It excludes, however, the negative impact on the human population of World War III and the wars with the Romulans and Klingons that appear in the standard Star Trek history timeline.)
Thus, at the fertility rate presented in the 300 years of future history shown in the dozen completed Star Trek TV series, and assuming a continuing life expectancy of eighty-five (which currently appears to have plateaued), but excluding any impacts from wars or plagues, the number of humans would decline by 93 percent over those three centuries, and would be under 50 million by 2400, the time of the end of the most recent Picard series. By then the number of humans left in the universe would be equivalent to the population of modern Sudan. And, projecting forward current population distributions, that remnant might well be mostly located in Sudan. It will certainly not be in outer space.
If we re-insert some realism to this scenario and exclude fantastical scenarios like replicators, robots, transfers of our consciousnesses to machines, and so forth, what becomes of humanity in the next 300 years? The welfare states of the twenty-first century will soon fail due to lack of taxpayers and workers to sustain the transfer payments at their core. For centuries the average age of society would always be sixty years old or older, with any democratic political system dominated by the need to expend most resources to support a permanent majority of elderly and other dependents.
It will be a world of shuttered schools and factories, with retirement facilities as the only stable industry, assuming any human civilization survives. With economies in continuing centuries long decline there would be no resources or demand for new construction, development or research. Instead, it would make more economic sense to scavenge the old infrastructure and technology. Creative and technologically innovative cultures of our time, including the California culture that dreamed of a Star Trek future, would have long since disappeared.
To the extent that humanity does not descend into a post-apocalyptic barbarity, some twenty-first century technology may be preserved and even advanced before the demographic winter advances too far. However, in such a world, the more likely science fiction precedent would be the one found in Isaac Asimov’s Caves of Steel. In that future, human space colonists live in isolation, only connecting electronically while limiting reproduction in order to conserve wealth. In any scenario, human civilizations would be depleted and aged. There would be no Starfleet, no Federation of Planets, and no colonization of other Earth-like planets (if there are any). No progressive vision of humanity’s future would be possible, because progressives are not bearing and raising enough children to populate such futures.
Progressive reactions to these hard demographic facts are an odd mirror of some conservatives’ reactions to climate science, which they resist in part because they do not like its political and economic implications. Progressives resist facing this dark demographic future because they do not want to acknowledge that addressing it would entail resurrecting the ancient female task of mothering future generations.
Perhaps in centuries our descendants will watch reruns of Star Trek, inspired by the then defunct culture of sunny California, and gawk at the scantily clad young space babes who Roddenberry kept sneaking on to his shows. If so, they will likely marvel that there was ever a time when humanity fantasized about exploring strange new worlds, seeking out new life and new civilizations, boldly going where no one had gone before, striving to be the answer to Dr. Fermi’s question.
Something could always happen to reverse the ongoing precipitous decline in fertility rates, although it is unclear what that might be. Certainly the decline appears to be resistant to government supplied financial incentives and child care assistance. However, a potential alternative does present itself in current real-world data. Certain religious groups are still having babies.
For example, alone among economically developed nations, Israel maintains an above-replacement fertility rate of about three (2.9 as of the most recent reports), twice the 1.5 average for OECD nations. This is primarily due to the high 6.6 fertility rate among ultra-orthodox haredi, but even most less religious Israelis maintain at least replacement fertility rates. For example, perhaps the best-known modern Israeli, actress Gal Gadot, has four children.
In the United States, although the community is too small to materially move the aggregate fertility rate yet, the number of Amish has grown from around 5,000 in 1900 to almost 400,000 today. Anecdotally, higher than average fertility seems to prevail among more tradionalist or conservative Catholics, evangelicals, and Mormons, but it is hard to isolate the fertility of these smaller communities from the secularizing majority in each religious group.
These trends were already in place in 2010 when political scientist Eric Kaufmann wrote Shall the Religious Inherit the Earth? There he argued that by 2085 as the “sea of humanity drains away” due to worldwide below-replacement fertility, high-fertility religious fundamentalists will become the “future of our species.” Initially most seen among smaller groups like “Old Order Anabaptists, Mormons, Haredi Jews, Laestadian Lutherans, Salafi Islamists and Quiverfull Protestants,” this development will become ever more apparent when they are joined by more numerous, if slightly less fertile but still fecund “mainstream Christian charismatics, Protestant fundamentalists and Islamists, all of whom are on the rise against demographically moribund seculars and moderates.”
Fifteen years later, Kaufmann’s predictions appear to be holding for the more insular of these groups. However, those who are more integrated with the larger modern society have not been immune to the vast worldwide tendency to have fewer babies. For example, historically Mormons tended to have one more child per family than the larger host society, a trend that continues to hold. But that means that the Mormon fertility rate has tracked the larger society’s downward trend to a point where even the Mormons’s vaunted fertility is barely above replacement.
Nonetheless, whatever humans exist after the close of this century, our species is going to be in ever increasing numbers the descendants of our traditionalist, religious, and socially conservative contemporaries. And whatever humanity’s future holds, it will not resemble the one portrayed in Star Trek.
Has Star Trek solved the Fermi Paradox? Are there no spacefaring civilizations because they will all ultimately spurn the burden of bearing and rearing their young? Does the coming demographic winter mean the end of visions of a prosperous future founded on carrying forward the technological advances that have powered our age? Let me propose one more thought experiment in the form of a rudimentary fan faction. Could we recast the Star Trek future with the kind of people who might actually be around two or three centuries from now?
Such a reframe would certainly violate Star Trek “canon.” Gene Roddenbery was an avowed atheist, and his Star Trek future had no place for religion. Some alien species were allowed religious beliefs, but they all admitted of an obvious naturalistic explanation. However, as our world exists now, religious humans appear to be the only future available.
“Religious humans appear to be the only future available.”
Instead of James Tiberius Kirk, Roddenberry’s Iowa-born, swashbuckling, womanizing alter ego, we would have a James Theophilus Kirk. He could still be born in Iowa, descendant of prolific Mennonite farmers. And he could still be an adventurous starship captain. However, he would also be an Aeltester of his congregation when he is back at the Enterprise’s home starbase on a colony planet. His wife, Janice Rand, and their seven children would live there.
Janice Rand was an Enterprise crew member in the first season of the original series. Played by actress Grace Lee Whitney, Rand was intended to be a possible romantic partner to Captain Kirk, but was dropped from the series so Kirk could romance other female characters (alien as well as human) unencumbered. (Although Whitney died in 2015, the addition of her character to this alternative lore would be symbolically appropriate, as she actually had two children and became an evangelical Christian later in life.) It would be unrealistic to have a Scot, a Russian, or a Japanese as officers, as these are unlikely to exist as distinct cultures after this century, but the crew could certainly include an African. The others might include an orthodox Jew, and perhaps an Indonesian and an Indian, ethnicities whose fertility is also currently falling but which may persist thanks to larger initial numbers.
Most critically, given that we are nowhere near any realistic means of superluminal travel, we would still need to include Star Trek’s main Fermi Paradox cheat, its vulcani ex machina. However, unlike Roddenberry’s coldly logical alien atheists, to have avoided succumbing to the Star Trek solution, our Vulcans would need to be theists. Rather than detecting some random technological advancement, their coming to Earth would be due to humanity’s achievement of a concord between the religious survivors of the societal and demographic collapse, cooperating in our species’ recovery. The Vulcans’ first contact with humans would be because we had become religious enough to be trusted with their advanced knowledge.
And thus we realize a different solution to Dr. Fermi’s paradox.