Ok, this kind of stuff makes my head hurt. Not because it is hard to understand, but because the scale of the universe is beyond what any person can comprehend.
I have this great discussion point I like to bring up with people because it gives me insight into their thought processes, so I will present it to you.
Imagine that the Earth was exactly the same. Same weather, same development, same continents, same everything...but it was the size of Jupiter. Would we have ever discovered other continents? How many satellites would it take to communicate around the world? How long would it take to fly to London? Weeks? Months? Would Columbus have ever even left land?
I love hypotheticals like this, because it really makes you think about scenarios and how things could be. Our Earth is SO huge, yet it is cosmically tiny. How could there not be life out there?