Wednesday, September 21, 2005

Is Life Elsewhere?

That title is supposed to be one of my exceedingly clever and erudite puns, this time on the title of Milan Kundera's Life is Elsewhere, but I confess that, as puns go, it is neither clever nor erudite, since the only connection between what I'm going to write about and the contents of that brilliant novel is the presence of the words "life", "elsewhere", and "is" in the title.

Sorry.

But anyway...is there life elsewhere? There are at least three ways of looking at this question. One way, defended by such popularizers of science as Carl Sagan and Isaac Asimov, says that the odds are that there is life elsewhere, and on the following grounds. The sun is just one of "billions and billions" of stars of its kind in the Milky Way galaxy. The Milky Way galaxy, in turn, is just one of "billions and billions" of galaxies of its kind in the observable universe. If life arose on Earth (which is probably just one of "billions and billions" of planets of its kind") then we know that it is possible for life to arise in such a place, and given the sheer number of such places out there "the odds are" that it has arisen in other such places.

The argument, in other words, is one grounded in probability.

Another view, defended by biologists such as Ernst Mayr, holds that the conditions necessary for the origins of life on earth are already so very complex as to make such origins extremely unlikely in the first place. That life arose on this planet at all, according to this view, is already something of a naturalistic miracle, and given the astronomical odds against precisely these initial conditions arising anywhere else in the universe in tandem, we are not warranted in believing that it has arisen anywhere else. For example, if the probability of there being the right mix of O2, CO2, and whatever elements in the atmosphere is, say, n, where n < 1; and the odds of the planet being a certain distance from its sun is x, where x < 1; and all the other odds for all the other components are also less than 1; well, to calculate the overall probability of such a state of affairs you must multiply all those numbers together, and since all those numbers are less than 1, the final product is going to be very, very, very small. That is, it will represent a very tiny probability.

So this argument, too, is grounded in probability, but it draws the opposite conclusion.

The third way of looking at this is a version of the second way. About six or seven years ago a mathematician argued that not only do the conditions on the planet have to be just right for life, but the position of the putative planet must be just like the earth's position in the Milky Way (about two-thirds of the way out from the center), because if you get too close to the center of the galaxy the radiation levels will be too great for life, and if you get too far away from the center of the galaxy there won't be a sufficient mix of molecular constituents for life. So we must reduce the number of "candidate" planets from "billions and billions" to--I don't know what, actually, maybe "millions of billions" or something like that. But it means that the odds are even worse for life arising elsewhere.

So much for the scientific view. My experience has been that certain scientists talk about life "out there" as though it is virtually certain that there is intelligent life out there somewhere, and I suspect that at least half of that is just wishful thinking, seeing as how there is absolutely no empirical evidence whatsoever that there is any life anywhere else, and most of the scientists we're talking about are supposed to be empiricists. But whatever. How about from a religious point of view? Is there any theological reason for endorsing one view rather than the other?

I myself am inclined to think that there is no other intelligent life out there, but I admit that there's no scientifically compelling reason to think that--but then neither is there any scientifically compelling reason to think otherwise. I can't really think of any theologically compelling reason to think that there's no intelligent life out there, either--my main problem with it is purely of my own making: how to make sense of the Incarnation. Our faith is a decidedly historical one, and a very physical one, in the sense that it appeals to facts about the created order of things in its explanation of the meaning of that created order. I can't help but wonder what the meaning of Jesus' birth in 4 BC in Bethlehem would be--would have been?--if there is--was?--intelligent life elsewhere in the kosmos. Would they have a revelation of their own? A Messiah? What of our Messiah's suffering and death? Were they not, in the end, once and for all? Or did God create other beings "in His Image" such that Jesus only came to save us because only we were fallen? That last thought, though, crosses the line into heresy. All of creation is redeemed by Christ's sacrifice, not just the human part of it. That means that the historical, factual, actual suffering, death and resurrection of a real live fully human being is an essential, necessary, and sufficient condition for the redemption of all of creation.

Perhaps humanity serves for the universe the role that the Jews serve for humanity: we are the "chosen species", as it were, representing all of the creatures created in His image. The Jews serve as an imago Dei for the rest of mankind, but mankind is the imago Dei for the whole universe. Now that's what I call real anthropocentrism! If it's true, though, one has to wonder how the rest of the universe is supposed to know about it.

It seems more likely, somehow, that it's just us. And what would be wrong with that? Why do we want (some of us, anyway), so very desperately, for there to be intelligent life out there somewhere? I sometimes wonder if the folks who long for extraterrestrial contact aren't somehow a little disappointed with what we've got here--perhaps there is more than a little misanthropy involved, or just a bit of dissatisfaction with one's lot in life. Sure, it would be really cool to run into Mr. Spock or something even ickier out there, but I'm not sure that I share the feeling that it would be so cool as to be positively disappointing if it turned out that we were the only ones here. Because even if we turn out to be the only ones here, we would not be alone. The folks who hope for alien contact probably don't even believe in angels, let alone the Communion of Saints. Or God. We are a community of human persons because God is a community of persons. There is no need to feel "alone", even if human beings turn out to be the only intelligent creatures (other than God and the angels) in the whole universe.

Pure speculation, of course--there may very well be billions and billions of intelligent species out there; maybe they all know about God or maybe none of them do or maybe a few do and a few don't. For me, though, whatever the case is with respect to extraterrestrial life, I know that I am not alone.

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