Anyway, if you'll allow me, I'd like to ramble a bit in an effort to describe (explain would be too ambitious) my idea (theory would be presumptuous) about extraterrestrial intelligence. In doing so, I will necessarily touch on the concept of god (lack of capitalization is intended), the Universe, the Big Bang Theory, and stuff like that.
The idea that our universe had no beginning and will have no ending comes and goes in cosmology (kind of like our universe, as you'll see). In fact, no less a light than Albert Einstein initially believed the universe was closed and steady state. But his own General Theory of Relativity required that the universe be either expanding or contracting, so Einstein created a "cosmological constant" to insert in his equations in order to make them conform to his belief in a steady state universe. He later came to see this as a mistake. Well, anyone could have told Albert that, don't you think?
Anyway, where the hell am I going with this. Let me think... Oh yeah, there were other respected astrophysicists/cosmologists who believed in an essentially eternal universe, but the discovery by Edwin Hubble that the universe appeared to be expanding and the further discovery of microwave background radiation predicted by the Big Bang Theory seemed to seal the deal -- Big Bang was king.
Not so fast (although the "singularity" that composed all that existed before anything existed and became The Universe did it in ten to the minus four seconds and that's damned fast). There are other theories of cosmological reality and they are pretty cool, e.g., parallel universes anyone?
Mathematical physicist Neil Turok theorizes that the universe cycles through expansions and contractions (the "Cyclic Universe" theory), and neither time nor the universe has a beginning or end. Google Turok and you can read all you want about "string theory" and "M-theory," and branes, and black holes, and try to figure it all out -- good luck with that.
My own "theory" is that the universe is and has always been, but it's nature changes because it's being pulled in and out of an infinite number of black holes (thus the appearance of expansion and contraction); think about pulling your socks inside out before you throw them in the wash and then pulling them back right side out when you pull them out of the dryer. If you don't wash your socks and want a different example, forget about it you stinker!
I posit this theory because I want you to expand your ability to conceptualize possibilities that are outside the realm of your physical being and your experience as such. Consider this for example, mathematical physicists like Neil Turok deal with many more than 3 dimensions (10 or more sometimes) when they cogitate on the nature of our universe. Imagine how many pairs of special glasses you'd have to wear to watch a movie in 10-D.
Now that your mind has expanded, consider your place in a universe that is infinite and eternal. You may see yourself as floating on an air mattress in a pool, in your backyard, in your neighborhood, in, say, Washington State, in the USA. So, on the North American continent, on the earth, which you may think of as floating around the sun with a bunch of other planets that form our Solar System.
Well fine, but keep going. Okay, so you know about the Milky Way Galaxy. Do you know that the only stars we see with the naked eye are all part of our Galaxy? And that there are an unknown number of galaxies (some say billions) in the universe? That seems really big, doesn't it. Maybe not. Maybe all this is just a gas bubble in the lower intestine of a super being that ate too much dark matter for dinner, and you're a microbe sitting on a piece of undigested fruit, say a blueberry -- our earth -- working with all the other microbes on the partially digested blueberry to turn it into fecal matter (you have to admit, we're doing a pretty good job).
The point is, that in a universe of essentially unknown size, we have no real point of reference for the size of our Galaxy, Solar System, planet, or ourselves. I will tell you this. We are larger than some of the things on this planet that we know about, like bacteria. We're a lot larger than those little buggers.
Again, in an earlier post I wrote about something called Cyanobacteria. This microbe is largely responsible for creating the earth as we know it. An interesting question is, how did it get here? Furthermore, we might ask if it exists only here, or has this particular bacterium migrated elsewhere? Do the bacteria we encounter exist because we exist, or do we exist because they exist?
There is some evidence that suggests certain bacteria were carried to earth on meteorites. The possibility that life first came to earth and indeed, was distributed throughout the universe by ejecta blasted from planets bombarded by huge meteors has spawned a theory of interstellar life called "panspermia" (or "transpermia"). The prospect was first proposed in the 1870s by physicists Lord Kelvin (British) and Hermann von Helmholtz (German).
A hundred years later, British astronomers Fred Hoyle and Chandra Wickramasinghe found new evidence for panspermia, traces of life in the dust of space. They also proposed that comets carry bacterial life across galaxies and protect it from radiation damage along the way because comets are largely made of water-ice.
James Lovelock's Gaia theory of the earth can be seen as complementary to the theory of panspermia, or vice versa, I don't know. In any case, it's intriguing to think of the earth as a living being in its own right, and more so if we accept that it's "life" was seeded from space.
Let's summarize. We have an eternal, infinite universe that contains the building blocks of life. Life on earth was seeded from somewhere in that infinite, eternal universe. Given this, there's no reason not to believe that many other life forms exist in many other parts of the universe. But are they "intelligent?"
The very question is posed in such a way that it once again anthropomorphizes our consideration of possibilities. Why? Because it's altogether possible that we humans are an integral part of a pervasive, self-perpetuating, cosmic intelligence, i.e., Cosmic Gaia, in which elemental life is transported via comets throughout the universe, making course corrections as the universe expands and contracts and planetary bodies form and are destroyed.
The universe exists in a state of homeostasis, forever and always. The intelligence necessary for that to happen has existed and will exist forever and ever. Right now, we are part of it. Some day, we'll be replaced. Our replacements will be wearing their socks wrong side out.