Back on topic, it was once theorized that there were some 10,000ish planets in our galaxie that were able to support life. This number was generated by statistics based on:
-The average number of planets in a given sector of start (stars:planet by area)
-That spread out over the whole area of our galaxy.
Now, that was over 10 years ago. Having studied the same are more throughly, we've found many more planets. Basically, it's mathematically improbable that there isn't life elsewhere.
Now, look at our own worlds history. The Earth formed, cooled, water condensed, and life began. In that order, almost as fast. In geologic time, life appeared in almost the same instant as liquid water. It's been theorized that life is a byproduct of liquid water.
It's there.
Oh wait, all this, fossils, other planets, etc. It's all made up by God to test our faith. Almost forgot!
http://www.commonsensemedia.org/reviews/images/4812.jpg