I usually only blog about issues on which I have some expertise, or at least sufficient knowledge to make points that have not been put forward by other commentators. But I am making an exception for the Fermi Paradox – the question of why we have not so far detected any intelligent extraterrestrial life. Astronomers and a few social scientists have been debating this issue for years. UFO enthusiasts, of course, believe the question has already been answered. But I think it deserves more attention than it has gotten so far from serious scholars in a variety of disciplines.

This recent Huffington Post article has a good summary of the issues involved, why they are important, and why they are much more difficult than we might at first think. It also describes some of the possible solutions to the Paradox proposed by various scholars. As the article explains, under plausible assumptions about the number of habitable planets out there, the likelihood of life arising, and the possibilities of communication and interstellar flight, we should by now have detected some intelligent aliens, perhaps even a great many:

SETI (Search for Extraterrestrial Intelligence) is an organization dedicated to listening for signals from other intelligent life. If we’re right that there are 100,000 or more intelligent civilizations in our galaxy, and even a fraction of them are sending out radio waves or laser beams or other modes of attempting to contact others, shouldn’t SETI’s satellite array pick up all kinds of signals?

But it hasn’t. Not one. Ever.

Where is everybody?

It gets stranger. Our sun is relatively young in the lifespan of the universe. There are far older stars with far older Earth-like planets, which should in theory mean civilizations far more advanced than our own. As an example, let’s compare our 4.54 billion-year-old Earth to a hypothetical 8 billion-year-old Planet X….

The technology and knowledge of a civilization only 1,000 years ahead of us could be as shocking to us as our world would be to a medieval person. A civilization 1 million years ahead of us might be as incomprehensible to us as human culture is to chimpanzees. And Planet X is 3.4 billion years ahead of us…

As the article explains, there could easily be numerous potential “Planet Xs” out there, which makes it more difficult to explain our failure to detect any intelligent extraterrestrial life at all. Thus, Enrico Fermi’s famous question – “Where is everybody?” – is not easy to answer. Obviously, there are numerous potential answers out there. Indeed, we have a lot more theories than data with which to assess them. Whatever the right answer is, it will have important implications for our future, for reasons that Oxford philosopher Nick Bostrom explains in this 2008 article.

I don’t have anything profound to say about this issue that hasn’t already been better said by others. But I do believe it is an extremely important question that deserves more attention from those in a better position to analyze it. Even if we can just narrow down the range of possible answers without zeroing in on the single correct one, that would be significant progress.