Democracy (the system) is enough to account for the seeming alien life-form which is Hillary and for whatever that thing is on Trump’s head. But as queer as Democracy is as a political organization, it cannot explain why we don’t see ETs zipping to and fro throughout the cosmos.
After all, the universe, scientists say, is several billion years old, containing lots of stars with planets similar to earth. Evolution, scientists promise to show some day but haven’t yet, accounts for the origin of life and for its non-progression to biological forms such as we (the obvious progression in the complexity of life that is observed is, some scientists say, only an artifact, because the observation of increasing complexity does not accord with some theories).
Anyway, by “such as” I mean capable of creating websites like this. As Enrico Fermi famously asked, “Where are the Martian bloggers?”
They are not here, they are not there. They appear to be nowhere. They appear not to exist. Yet theory says they should. Which should we believe? Observation or theory?
Fermi’s question isn’t a paradox unless you accept certain premises, and among those premises is the unconfirmed-by-any-observation theory that solely natural processes produced life on our planet, and thus should also produce life on other planets similar to ours. Well, and maybe this is a true theory. I certainly don’t know, and neither do you, because, as said, natural biogenesis hasn’t been observed. It is only a surmise.
If it is a true theory—which, again, nobody knows—then Fermi was right to ask his question, for something must then account for the lack of life. If instead the theory is false, there is no paradox and all is right with the worlds.
Incidentally, science deals only with that which can be observed; that which cannot be observed falls under religion or metaphysics. Such that if you accept or deny the a theory in the absence of observation you are doing so on faith—not that there’s anything wrong with that.
Suppose, then, natural biogenesis is a true theory, for supposing it is false answers our main question and we are done.
We next need to assume another premise, which is that evolution invariably, or largely, or even only sometimes, produces life-forms capable of blogging. Nobody knows if this premise, or rather theory, is true, either. We only have ourselves to go by, and perhaps there was some event which makes us unique. You can’t tell by the single observation that is we. The evidence of us supports equally the theory’s truth and its falsity (and that we’re sui generis). But we may as well assume it’s true, because without it we again have our answer that there is no paradox.
Enter Aditya Chopra and Charles H. Lineweaver and their paper “The Case for a Gaian Bottleneck: The Biology of Habitability” in Astrobiology (which, given the absence of actual observations, you’d guess is a thin journal; a simpler summary is here). These authors answer the paradox by invoking planetary agency, pace, “If life emerges on a planet, it only rarely evolves quickly enough to regulate greenhouse gases and albedo, thereby maintaining surface temperatures compatible with liquid water and habitability” and as such extinction of nascent life-forms is the norm.
Life, under the Gaian theory, provides its own means of living. Unanswered is how life originates at all, since without the Gaian goddess imparting the necessary initial spark, life can’t massage an atmosphere or terrain into regimes more comfortable for itself.
But we assumed life “got going” via some as-yet undiscovered mechanism. We also assumed that it got going in the same way as on earth, and did not get going such that, say, uranium and not carbon was the basic building block, an option considered by the authors.
There is no proof either for non-carbon life-forms, of course, only surmises, wishes, and guesses.
The authors speak of various kinds of Gaian bottlenecks and the difficulties life has bootstrapping itself under various other unknown and theories. These are of minor interest. What is more to the point is that all of the theories are observation-free. There is no confirmation, or disconfirmation, of any of them. And there are more theories than these the authors show. Heck, every working scientist probably has at least one.
In order to confirm or disconfirm any of the theories we’ve used so far—from life’s start, to evolution of bloggers, to Gaian control of other planets—requires that which we do not have, observations. To say we will have observations is (again) mere faith. I certainly don’t know if we will, and neither do you.
Lastly, the authors admit “The Universe does not seem to be teeming with life. This could be an observational selection effect: it is teeming with life, but we just have not been able to detect it yet.”
Yes, true: it could be teeming. Or it could be deader than a bureaucrat’s sympathy. The observations we have are consistent with both.