This is an excellent lecture on the question of life in the Universe and why we should be hesitant to make pontifical statements in this regard.
We just do not know enough in many areas to even present an hypothesis.
What are the odds of you being here to read this statement? Think of all the fantastic coincidences that must have taken place for you to be here to read this. Just the fact that your Mother and Father had to meet to produce you may have been highly improbable. Go back in time with all the pairings which had to have taken place, and eventually you arrive at some primitive RNA molecule attempting to survive and replicate 4 Billion years ago. Think of all the steps necessary to arrive today at you reading this line.