We Are Not Alone... or Are We?
Over the course of my lifetime, there's been an interesting little change in the common wisdom.
I can remember a time in my childhood when the unshakable sessile assumption among the bien pensants was that certainly life was nowhere to be found except here in our little corner of the universe. There were no planets outside our solar system. There was no life except on Earth. There was no intelligent life except for Man. Any disagreement with this heavy-jowled orthodoxy was met with a loud, bone-shaking, vibrato bass "NOOOOOOOOO!!!"
I myself, as a kid, was one of the few known dissenters from this wisdom. I followed astronomy the way some kids follow sports. I knew the name, diameter, orbital period, and distance from primary of every moon then known in the solar system. I knew all the stats on the Mercury and Vostok missions, who, when, how many orbits. I had a stack of astronomy books. And you could not fool me: of course stars with planets were widespread in the universe; of course life was commonly to be found on other planets throughout the cosmos; of course intelligent life reared its pesky head not so very infrequently where life was to be found.
Well. I haven't changed since. But the common wisdom has. Stars with planets, hard to deny it any longer when astronomers are discovering them out there left and right. Life out there, the heavy-jowled orthodoxy has done a 180, and now you'd get a leaden, angry "NOOOOOOOOO!!!" if you denied that life exists elsewhere. Likewise the received wisdom is that "we are not alone" in the intelligent-life department, either.
I only wish I could resist the impression that the turning point in the common wisdom was the entry of science fiction into the cultural mainstream. I grew up in an era when science fiction was still marginal and disreputable and rather grubby, and people scoffed at the possibility of planets and life and intelligence elsewhere in the universe. Then, in the late 1970s, science fiction went mainstream in our culture. Star Wars was what did it. And unless I'm missing my guess, that was also about the point when more and more "respectable" people, including those of the white-lab-coat persuasion, began to give credence to the possibility of planets, life, and intelligence out there.
This is the way human culture often works, and shifts and changes its outlook. Kekulé's dream of a hoop-snake, and the structure of the benzene molecule: cultures as well as individuals go "aha!" for the most pictorial and phantastic of reasons, which turn out in the long run to have been correct after all. Then in hindsight the guardians of the received wisdom try to airbrush the abductive leap, the hoop-snake, the science-fiction movies out of the picture: makes it harder to be heavy-jowled and leaden and sessile and beyond all question when it's known that poetry was one of your ancestors.
So. Extrasolar planets already discovered by the bushel, and they seem to be widespread. The biologist would be hard to find who would deny any longer that life is probably common out there. But as for intelligent life elsewhere in the universe... well, now there's the rub. We are not alone... or are we?
Because, you see, for quite some time now we've been listening. If there's anyone out there who's broadcasting on radio frequencies, you'd think we'd have picked them up. Wouldn't you? Only... nothing but the silence of the interstellar deep.
As the physicist Enrico Fermi is said to have put it, "Where are they?"
This gives rise to the Fermi paradox, "the apparent contradiction between high estimates of the probability of the existence of extraterrestrial civilizations and the lack of evidence for or contact with such civilizations." One would think, on the basis of today's common wisdom, that we are not alone. Yet as far as we can tell, it seems we are alone. What gives?
At present one can only speculate. I used to speculate about this as a kid, back when I had already embraced today's common wisdom 40 years and more in advance. Back when I was writing reams of science-fiction stories in high school, my surmise was that intelligent life is not uncommon in the universe, but that most intelligent life differs radically from us in its psychology. "Alien psychology" means really, really, really alien psychology.
Imagine a species of birds whose nervous system is hardwired for radio transceiving, forming an intelligent collective mind, as in my recent short story, "Skeetchee." Imagine something like Fredric Brown's electromagnetically-based life forms, in his classic story "The Waveries." Imagine life forms so alien that you couldn't even begin to conceive what they're up to, or why.
I also used to speculate as a youngster that, even if intelligent life was not uncommon, technologically oriented intelligent life was. That "alien psychology" angle again. There are a thousand and one things an alien culture might be up to, without being up to anything that involved high technology. Or even if they were technologically inclined, they might lack the psychological push that drives us, as humans, to expand outward like a gas spreading to fill a psychological formless void: an alien race might be technological without being in the least technocratic.
So I used to think, 35 and 40 years ago. If my speculations on this question differ today, it is only by the addition of a darker strand: if we are alone in this vast universe, it may be because intelligent races inevitably succumb to self-destruction very shortly after they achieve high technology. The fate of the Krell, annihilated in a single night, in the classic science-fiction movie Forbidden Planet. "Monsters from the id." How long do you think the human race would survive, if we gained freedom from physical instrumentality, and removed every last obstacle between the Thought and the Deed?
Well. We are not alone... or are we? At present we can only speculate. Some day we may find out more. I for one would be curious to know.