3.) If we don’t find life in the places and under the conditions where we expect it, can that prove the existence of God? Certainly, there are people that will argue that it does. But to me, that’s a terrible way to place your faith. Consider this:
“Do you want or need your belief in a divine or supernatural origin to the Universe to be based in something that could be scientifically disproven?”
I am very open about not being a man of faith myself, but of having tremendous respect for those who are believers. The wonderful thing about science is that it is for everybody who’s willing to look to the Universe itself to find out more information about it. Why would your belief in God require that science give a specific answer to this question that we don’t yet know the answer to? Will your faith be shaken if we find that, hey, guess what, chemistry works to form life on other worlds the same way it worked in the past on this one? Will you feel like you’ve achieved some sort of spiritual victory if we scour the galaxy and find that human beings are the most intelligent species on all the worlds of the Milky Way?
Or, can your beliefs — whatever they are — stand up to whatever scientific truths the Universe reveals about itself, regardless of what they are? In the professional opinion of practically all scientists who study the Universe, it is very likely that there is life on other worlds, and that there’s a very good chance — if we invest in looking for it — that we’ll be able to find the first biological signatures on other worlds within a single generation. Whether there’s intelligent life beyond Earth, or more specifically, intelligent life beyond Earth in our galaxy that’s still alive right now, is a more dubious proposition, but the outcome of this scientific question in no way favors or disfavors the existence of God, any more than the order of whether fish or birds evolved first on Earth favors or disfavors a deity’s existence.