Every age has its fantasies. For over a thousand years in Europe the Christian mythology conditioned people to think in terms of ghouls and goblins, gods and angels. Not surprisingly, from time to time susceptible individuals imagined they saw miracles or celestial creatures; even today the ignorant and simple-minded believe they see statues weeping blood or moving spontaneously.
We humans, with our tiny ape-brains, are supremely credulous creatures.
Today our fantasies are shaped by sci-fi, which is nothing more than Cowboys & Indians In Space. Not surprisingly from time to time susceptible individuals imagine they see UFOs or are abducted by aliens whose raison d’etre is apparently to gain intimate knowledge of our posterior parts.
While people in backward countries still imagine that angels walk among us and that aliens are “out there,” most educated people in Western societies aren’t obsessed about upsetting angelic visitors or preparing a for an impromptu rectal probe.
We do, however, succumb to a fallacy that is no less lacking in substance. Astonishingly, this fallacy has even been promoted by people who ought to know better. From the so-called Fermi Paradox to the ramblings of Stephen Hawking, we see a persistent delusion regarding the probability of our species ever encountering a sophisticated technologically advanced alien species.
So let us examine this notion and try to determine how credible it may be.
It’s always difficult to argue anything from a single example, and all we have is our single example of homo sapiens. Yet even this single example holds plenty of clues. We can begin by noting that we’ve existed as a distinct species for somewhere between 400,000 years and 200,000 years. For 96% of that time (taking the median value of 300,000 years) we were clinging on to survival at the margin, eking out a simple existence with primitive tools. It’s easy to imagine we’d have gone extinct without ever making any kind of lasting impact. Lacking strong muscles, powerful jaws, and sharp claws, we used our brains in much the same way that those other opportunists the rats and corvids do.
But rats and corvids haven’t developed sophisticated technological civilizations. There was no inevitability about our unique path.
So what happened to change our historical trajectory?
After the last ice age, a mutation arose in grass that resulted in the energy-rich kernel falling more easily from the stalk and detaching from its protective coating. Within a thousand years or so, small groups of humans had begun to take advantage of this change. They learned to scavenge the seed-kernels by flailing so as to separate the wheat from the chaff. They learned to plant some of the seeds, protect them from birds, and wait until they yielded new bounty several months later. In other words, our distant ancestors began to learn the crafts of agriculture.
In consequence, human society changed forever. Instead of existing in relatively small numbers, we began to clump together in villages that grew into towns and towns that ultimately grew into cities. Somewhere between 8,000 years ago and 6,000 years ago the first true city-states emerged. We have a few records from the later incarnations: Babylon, Mesopotamia, and Egypt.
The astonishing changes of massively increased social and organizational complexity, the development of permanent records utilizing writing and arithmetic, and the emergence of gods coalesced from thousands of tribal cult deities, were all made possible because agriculture provided a modest surplus of calories. This modest surplus enabled the most momentous change in human history: specialization.
When each of us had to scavenge for our dinner, none of us really specialized. Yes, one or two members of the group would be better hunters or better flint-nappers, but we all did more or less the same things in the same way. In consequence, innovation happened rarely. Our tools remained unchanged for tens of thousands of years. Generation after generation lived as their ancestors had lived. A human born 200,000 years ago could be transported to 40,000 years ago and almost nothing would seem new to them. Compare that with our modern world: a person from 200 years ago transported to today would find nearly everything to be utterly different from what they were used to.
Our astonishing rate of change is possible only because, thanks to a surplus of calories, people can specialize. People who have an aptitude for making pots can specialize in making pots and trade them for food and clothing. Those who specialize in making clothes can trade clothes for pots and food. With specialization comes slow but sure improvements that today we call innovations. At the beginning of the process, innovations are infrequent and incremental; later, as empirically-based science begins to emerge around five hundred years ago, innovations become more frequent and more radical. Shakespeare wrote his plays using a quill pen scratching across parchment; today’s playwright types on a laptop and stores the results on a server thousands of kilometers distant. Cloth is no longer woven by hand on crude looms but spun by machines far faster than any human could ever accomplish. We no longer rely on horses to cover distance. All of our modern shiny toys are the result of hundreds of years of cumulative innovation and improvement.
But if grass hadn’t developed a fortuitous genetic mutation, none of our civilizations would ever have emerged.
Cetaceans are intelligent, as are elephants. But neither will ever develop even rudimentary technological civilizations. Intelligence without (i) sustained calorific surplus, and (ii) the right kind of environment-phenotype match, simply remains within the domain of generic social interaction. Whales and dolphins and elephants have quite complex societies and even appear to have rudimentary languages; what they will never have is laptops and MRI machines. The environment-phenotype combinations are simply unsuitable.
Now let us amble sideways to consider the problem of spacetime. Let us, for the sake of argument, agree that we live in a very large universe. Currently we can detect around 2 x 10¹² galaxies and yet only 1.4% of them are even theoretically accessible to us because of the fact the universe is expanding. This still leaves an impressive number of galaxies, within which are billions of stars around which probably tens of billions of planets orbit.
Personally I think it’s folly to impose on alien life the constraints operating on our own particular forms here on Earth. I don’t think we need to assume a “goldilocks zone” nor that life can only emerge on planets like ours with a solid surface and a thin smear of atmosphere and liquid water. It may even be the case that protective magnetic fields aren’t necessarily essential either.
But even if we take the widest view of the potential for life to emerge elsewhere, this doesn’t help us when it comes to the probability of meeting little green creatures piloting their spacecraft towards the nearest human anus.
The very size of space is what defeats us. Sure, there are around 6 x 10¹⁰ galaxies we can theoretically interact with, but even the closest (Andromeda) is 2.5 million light-years distant. In other words, if some alien civilization in the Andromeda galaxy decided to visit the Milky Way, and if they had amazing technology that could transport them at 99% of lightspeed, the journey would take them just under three million years. While it’s amusing to conjure up space magic like Alcubierre drives, we ought to leave such things to cheap sci-fi. Otherwise we may as well argue that benevolent angels will simply whisk us between the stars while dancing on the heads of pins.
Assuming that aliens in Andromeda have far better things to do with their time than spend millions of years on a journey to nowhere, we have to accept that we’re restricted to our own backyard.
So we’re confined to our own galaxy if we want to imagine some technological alien civilization. Our galaxy likely contains around 2 x 10¹⁰ stars, but again nearly all of these are inaccessible to us unless we think journeys lasting 50,000 years are feasible. Elon Musk is doubtless already planning a galaxy-class megaship that will consume two trillion dollars of naïve venture capital, but the rest of us can be spared this kind of delusional nonsense.
Let’s assume that our short human lifespan is not necessarily typical of life elsewhere. Perhaps there are animal-like creatures (meaning that they have the capacity for independent movement) whose lifespans are much longer, perhaps as a result of understanding the various processes involved in ageing, perhaps as a result of evolution. Whatever the case, let’s imagine that a thousand Earth-years is a reasonable lifespan. In which case journeys lasting a hundred years could seem reasonable. So now we’ve a sphere around our own location of approximately 75 light years in radius (assuming this putative alien species has really impressive technology).
Unfortunately this turns out to be not a tremendously impressive number of stars. Worse still, we’ve so far ignored the problem of time. Imagine some advanced alien civilization coming into existence 20 light-years away. Unfortunately, they reached their technological period two million years ago. That’s the merest blink of an eye in universal times, but an unbridgeable gap for living creatures. Two million years ago our distant ancestors hadn’t developed language and were barely using rocks and bones to smash things.
And it gets worse. Our galaxy is around 13.5 billion years old, having formed early in the life of the universe. Assuming most life requires a reasonable mix of heavy elements which are created by older suns and by supernova, complex life equivalent to our eukaryotes could have arisen as long ago as 6 billion years under favorable local circumstances. Given the many variables involved, it’s not difficult to speculate that technologically sophisticated civilizations could have sprung into existence within our nominal 75-light-year radius several times since then. But the chances of overlapping in time with our own technological civilization are effectively zero.
True Believers imagine that technological civilizations must end up merging with machines to become immortal, but that particular fantasy has no more substance in necessity than does the disturbing fantasy of little green rectally-obsessed interstellar perverts.
As all intelligent social life appears to end up in the same situation, which is in competition with others of its own kind, it would be reasonable to argue that the duration of any sophisticated technological civilization is likely to be quite short. Our own brain-dead mismanagement of Earth would support this argument, as would the fact we’re highly likely to accidentally exterminate ourselves within the next two hundred years. Our technologies merely amplify our inherent follies. Those follies arise from a combination of limited intellect combined with perpetual competition with our peers. It is extremely difficult to hypothesize any intelligent species that will not inevitably fall into the same trap and thus suffer the same fate we’re almost certainly going to suffer.
Consequently, for us to encounter any technological alien life (rectally-oriented or otherwise) we’d need an astonishing coincidence in spacetime: physically and temporally close enough to overlap with our own brief moment in the technological sun.
Given that we’re talking about literally astronomical odds, one would need to be either hopelessly ignorant of the pertinent facts or hopelessly optimistic in the face of the pertinent facts to believe that any human-alien encounter is possible, even if we somehow manage to survive another thousand years before we blunder into self-induced extinction.
We are thus, to all intents and purposes, alone in the universe. We are therefore stewards of this fragile and amazing planet and no grownups are coming to help us mend our ways. Perhaps we need to focus more on trying not to destroy the one place we know we’re evolved to inhabit, and on trying not to destroy the complex ecosystems essential to preserving all life on Earth, than on focusing on teenage boy tech fantasies about billionaires’ panic rooms on barren rocky planets lacking absolutely everything we need for survival.
Yes, no matter how inept and destructive we are during our brief existence as a species, the Earth will recover from our stupidities and in ten million years it will be as if we never existed. Mass extinctions create new opportunities for evolution to improvise and adapt and so life on Earth will continue regardless of how badly we screw things up.
But maybe, just maybe, we ought to be a lot less focused on fantasies about aliens and a great deal more focused on trying to be less irresponsible here and now.
Or, conversely, we should hurry up and finish the job as quickly as possible, before we drag more species into extinction alongside us.
Either way, aliens aren’t coming to help.