2 posts tagged “aliens”

The ever-wonderful Nick Bostrom, who to my knowledge was the first to argue scientifically that we are overwhelmingly more likely to be living in a computer simulation than otherwise, has a short essay on his hope that we are alone in the universe. The hinge of his argument is the existence of a "Great Filter", some step along the path from planetary formation to the emergence of intelligent, space-colonizing life requiring such an improbable amount of luck that it almost never occurs. If life existed on Mars or elsewhere in our cosmic backyard, then this Great Filter is most likely to remain ahead of us.

Are we too parochial in our search for alien life? Can we define life, can we set limits on where it can or cannot exist, on what chemicals and in what environments it can and cannot persist? I'm put in mind of the engineers who believed train travel would be impossible for human passengers because above 25mph all the air would be forced out of the carriages. More probing analysis of the alien life question is here at the FQXi community blog.