A probabalistic analysis of the state of life on earth and how it was formed lead us to come to a few conclusions that can be held as facts:
1. It is possible that life can come about on a planet. This is evidenced by the fact that there is life on earth.
2. We live in a very large universe that has many trillions of stars. We are discovering now that many of those stars have planets, and thus logic would dictate that spread across these many many planets there would be some planets with similar conditions to Earth.
I would agree that probability is in favour of the existance of extraterrestrial life, and I would consider such a discovery inevitable. I, however, am a man who sincerely believes in science and I do not draw conclusions without evidence. Probability is not science and it doesn't decide the truth of things. Regardless of how likely something is to happen, there is a possibility- however remote- that it won't happen. As such I wouldn't be so brazen as to assume that life must exist merely because probability says so. Until we have concrete, irrefutable evidence that life exists elsewhere in the galaxy I don't believe that there is.
I should clarify, however, that I believe in extraterrestrial life. I don't think that intelligent life is likely to have made physical contact with us, but I still believe that life- in some form or another- is out there. I maintain an understanding, however, that what I believe and what I know are two very different things. Beliefs can be well reasoned or not but facts are indesputeable.
