Would finding life on Mars be such a bad thing as some philosophers have stated.
At the start of June the NASA Phoenix probe (which I am not sure is named because of the city of Phoenix, or perhaps because a past mission went down in flames) made a safe and successful landing at the pole of the Red Planet. Ostensibly this trip, having been planned out for the eons of time it takes to organize these things, is about sampling for water. But there are of course many who would be happy to see it instead as a quest for life. It was only a few months previous to this that a NASA photograph caused a stir purporting to show an alien figure perched on a rock. While this was mainly reported with tongue firmly in cheek, it clearly caused interest. We are fascinated by the idea of life on other worlds, and spend a lot of time imagining it in the arts. No doubt too some people will be studying the numerous pictures about to be sent back from the Phoenix probe in great detail, on the lookout for the elusive little green men.
Philosopher Nick Bostrom has gone on record saying that he hopes any searches for extraterrestrial life fail (MIT Technology Review, 2008). He would be more than happy if the Phoenix probe finds just dust and rock, maybe some water, and hopes that the various searches for life outside of the solar system listening to the sky never find the airwaves polluted by an old time alien rap song. You might be wondering why this is, after all, many people would greet the news of life outside of this planet as a wonderful, miraculous, thing, if that isn't too strong a word. Wouldn’t we have our experiences improved if we know we have a friend somewhere across the vast ocean of void? Though, to be fair, having watched the Eurovision Song Contest this year, I too can see a reason not to expand our circle of cultures too much. Indeed, some of those performances verged on the "alien" side. But that's not the real reason to fear the discovery of life. Bostrom tells us it is far more important than that; the real reason could spell the end of civilization as we know it. Doomsday could be right around the corner.
Bostrom points out that for some reason we are completely alone in our galaxy. As far as we know there is no solid evidence of extraterrestrials having visited this world, or sent us a message across space. Intelligent life is rare, and could, for all we know, only have occurred just this one time in the universe; namely, us, and yes, this could be as good as it gets. Bostrom refers to what he calls a "great filter" that must exist to explain our solitude and is somehow (the reason doesn't matter too much) stopping the universe being full of advanced, sentient beings. Possible candidates would be genocidal destructive tendencies, nuclear wars, or some scientific advance that when discovered wipes out the discoverers before anyone can say high energy particle accelerator. On the other end of the scale, it could equally just be that the formation of self-replicating molecules, the precursors to life, are incredibly unlikely and that’s why there isn’t much of it about. But again the actual reason is not important and can be speculated elsewhere.
What is far more prescient and important for us, or at least should be if we are worried about our likely survival chances, is whether we have already passed through the great filter and won, or whether it is still to come, and hence it is likely we will lose. Bostrom argues that if we were to find evidence of a long-dead advanced civilization on Mars this would be catastrophic news: If advanced intelligent life exists in a few other places in the universe, but not everywhere, then it is likely that the great filter does not involve difficulties in the early stages of starting life; life may well spring up everywhere as is its want, it could have happened throughout the solar system, from underwater cities on the icy moons of Jupiter to vast skyscapes in the gas clouds of Venus. But having sprung up, there must be some point in evolution, that we may soon be reaching, that stops advanced life being prevalent. It got to countless other civilizations, metaphorically snuffing them out in their sleep, perhaps, and it will get us too, maybe soon. Equally if the probe were to find not advanced civilisation, but the remains of a Martian microbe or bunny rabbit, it would imply that whatever stage of evolution was found elsewhere is relatively easy to get to on any planet, ergo the big tests are ahead of us.
But let's take stock for a moment and ask if finding life elsewhere would really be that bad. First, life on Mars actually tells us nothing about the statistical likelihood of our imminent doom. Cross contamination - space rocks flying from Mars to Earth and back again - prevents any meaningful conclusions from being drawn. So while Bostrom’s point is more pertinent when discussing life in other far away star systems, it is not so worrying if life is found to have existed on Mars. It could just be life here started on a tiny rock hurtling through space that fractured before crashing into both Earth and Mars. That said it is clear that the same conclusion would not be true of extra-solar life, the further away the less likely we had a common ancestor.
SETI has spent a great deal of money and effort searching for life elsewhere. Although it famously had its funding cut by government sources, a home version that can be installed on computers to search as part of a screensaver is still popular. Clearly there is a thirst to find some forms of life out there even if it is taking place during coffee breaks the majority of the time. So far there has been very little success, though it is a needle in a haystack kind of task. The question is would discovering life via an extraterrestrial signal, perhaps the first ten digits of pi or something, still be such a devastating moment as Bostrom suggests?
Personally I believe that being alone, having passed through the great filter, or not, would be far worse. What an ever more pointless existence we would lead, masters of all around us, but no one but ourselves to share in the wonder. What kind of world would we live in now if ancient Europeans found the Americas and Asia to be devoid of life and simply waiting for them to arrive? Do you imagine the court of Spain sat in fear should Columbus report other races existing across the Atlantic, even remnants of them? Of course not. But they could have used the same arguments we now use as we look out across to the shorelines of other stars. Life is for experiencing, for comparing different points of view on the same plane of existence. And it is in that wealth that living beings prosper. So what if we are soon doomed to extinction? I think that misses the point. There is nothing we can do about it; so let us live now continuing in our wonder, and fear not foreign bodies.
