An interesting proposition, and one I find to be completely incorrect.... but interesting.
As for the "ETs" visiting earth. That's as flimsy and fabricated as any religious belief. There's no verifiable proof, nothing that holds up to scrutiny.
As for there being some level of "life" somewhere in the universe, that's unproveable (until we travel to a place where it exists). However, if you believe in evolution, and you believe in statistics and probability theory, then it is reasonable to state that the odds are strong there is some form of life elsewhere, with the odds reducing as you increase the complexity of said life. This is in NO WAY a proof though, just probability theory.
You seem to think that we are equally likely to encounter some ghost/demon/spirit as we are to encounter some form of non-earth based life though. Am I correct in that re-statement?
I'm going to say you're likely correct (if by "we" you mean you and i) simply because within our short lives neither of us will encounter the statistically likely extra-terrestrial life (since that level of space travel is not happening any time soon) and the other category doesn't likely exist.
However, if you're using the "we" as humanity... then you're probably wrong. One category has a probability associated with its existence, something which given sufficient time will ultimately occur. The "supernatural" category has no probability associated with its existence, and no evidence of its existence. Time is not on its side.
victor809 wrote: