A few weeks ago (October 12, 2014) I wrote a blog post about the immense distances between stars and their planetary systems. The distances are so large as to make travel between star systems very difficult, if not impossible. Now I come across an article on Yahoo Finance entitled “Here’s Why A Leading Futurist Hopes We Don’t Find Life On Mars.” It’s a reprint of an article from Business Insider (which is why it was in Yahoo Finance). The article is about Nick Bostrom of Oxford University who thinks that if we find life on Mars or signs of previous life on Mars, it will be a bad thing. A very bad thing. He’s concerned that the presence of life on Mars either now or in the past would indicate that life may have developed in many other places in the Milky Way Galaxy, and that could be bad for us. Not bad in the sense of aliens coming to destroy us, but of us destroying ourselves.
Dr. Bostrom postulates that every civilization that develops on a planet somewhere has to go through a “Great Filter” sometime in it’s lifetime. But he doesn’t know if Earth has gone through that filter yet or not. That filter is hypothesized to cut down the number of civilizations that can develop the ability to travel from star system to star system. It’s a hypothetical reason why we haven’t been visited by other civilizations. But does it mean the Earth is about to go through a filter like that? Or will we continue to evolve and develop the ability to travel to another planet outside our solar system?
I’ve heard the “Great Filter” concept before in conversations and in meetings. Personally I have my doubts that it even exists. It’s virtually certain that we haven’t been visited by extraterrestrial aliens, but I don’t believe that we have to postulate a complex idea such as a global cataclysm that wipes out all life and prevents earthlings from populating the stars. That doesn’t mean I don’t believe in life on other planets, I do. But the distances between planets are so great as to make it extremely difficult to make the trip. The concept of a “Great Filter” is strictly hypothetical. There’s no evidence to back it up. In that sense it’s like science fiction, a figment of someone’s imagination.
Dr. Bostrom hopes that the “Great Filter” is in our past, though what cataclysm he thinks makes up that filter, I’m not sure, and how he gets from the filter being in our past to hope for the future escapes me, but I’m hopeful for the future myself. I’m sure we’re not alone in the galaxy, but the chances of meeting another civilization are so infinitesimally small that I think we ought to drop the whole subject and go on about the business of exploring our solar system. There’s too much interesting stuff out there to worry about who else might be out there.