I voted for two, interstellar travel of any distance is probably either impractical or impossible. But humans aren't that interesting is another good bet. I have one more. It seems every other scifi book I read these days involving interstellar travel by humans includes some sort of moral prohibition on revealing ourselves to species who have not yet invented interstellar travel. So what if they are hiding from us for our own good?
But ultimately, I don't think we really know how likely intelligent life outside of our solar system really is. After all we only have one example.
But ultimately, I don't think we really know how likely intelligent life outside of our solar system really is. After all we only have one example.
If there is a god, I want to believe that there is a god. If there is not a god, I want to believe that there is no god.