[bananarama]

Originally posted by James
There's a theory that if intelligent life had ever developed in the universe before life on Earth it should have had time by now to travel to, explore and settle on every planetary system in the universe (or was it galaxy, can't remember).

Therefore no other intelligent life has existed away from the Earth because we don't have any evidence of aliens exploring or colonising this planet in its past. QED.

But it's just a theory...

I watched 2001 on TV the other day again. Great film.

Problem with that theory is how do we know that we and the rest of life on this planet is not the result of some sort of alien landing from the past. The state of intelligent life on this planet could be as a result of a previous alien intelligence that lost it's knowledge and capabilities once its landing craft and original occupants had died. Leaving behind their offspring with no knowledge or technology to speak of.....Hence to-day mankind (The original aliens) is slowly regaining technical capabilities it used to have.......