>>Do you remember when people were seen as crazy for believing aliens?
Yup... My dad ridiculed me (lightly) for enjoying Star Trek... At one point, he said, "You know, people with pointed ears aren't real...right?" I said, "Not that we know of right now..."
>>In my opinion you're crazy if you don't believe that aliens exist.
Maybe... I think with the discovery of extra-solar worlds, and the sheer number of stars with planets out there, the concept of intelligence beyond Earth is far more acceptable today than it was 50 or 100 years ago. That *still* doesn't mean any exist, however... while I think there must be life out there - that's just my opinion.... and, it could turn out to be wrong. We'll just have to wait for evidence (either way).
>>They're probably not on this planet, but on some other planet.
I doubt our world could contain *two* separate intelligence species... one or the other would seek to dominate. So... on Earth - it's just us.
>>I mean, all of these planets in the entire solar system and you believe earth is the
>>ONLY one that can support life.
Well... in *our* solar system, I'd place the odds of life on another planet (or one of their moons) pretty low... There may be oceans under the ice of the moons of Jupiter and Saturn - but... I still think life - of any kind - has a low probability of existing there... But - not impossible, I have to admit. Mars might have had microbial life early in it's history, or maybe it lost its atmosphere before life had a chance to develop... Probably we'd need boots on the ground to make that discovery.
But - in our whole *galaxy*... with 250 billion stars, and upwards of a *trillion* planets... I'd say at least a few of them out there would be Earth-like enough to have not only generated life, but have advanced civilizations on them... That's only an opinion for now - and, like I said... could turn out to be wrong...