QUOTE (Lilly @ Jun 15 2008, 06:25 AM)

Very logical extrapolation, either hypothesis (humans from a parallel universe or from our own future) is as reasonable an explanation as aliens from another planet. This is the real problem here; just because a hypothesis is logical, and fits all the parameters of what's being observed, doesn't make it definitive (aka, the 'correct' hypothesis at the exclusion of any and all other possible hypotheses).
And, as you certainly know, no one has to "prove you wrong"....the burden always falls on those making the claim. When it comes to science the burden of proof is a tall order to fill, far beyond that needed for 'personal proof'. Those who've seen enough to personally convince themselves of extraterrestrial visitation need to keep this in mind.
No offense intended Lilly, but I'll be honest: I was just taking the p*** with my post. Nothing really but very subtle humor.
Your post though, is very reasonable, and I agree with it 100%. And that's no joke.
A comment and question though to those who argue that "it would be arrogant of us to think we're the only life in the universe"....I firmly believe we aren't the only life in the universe, but I also feel it would be very arrogant of us to think out of all the planets in the universe, ET has visited us. What is so special about Earth that some species more advanced than we would travel trillions of miles to investigate us? Sure, you can always answer, "Well, why not us?" but that doesn't answer the question. Our nuclear technology? It poses no danger to the Moon, much less the rest of the solar system, and forget about the rest of the galaxy. A hybrid species? For us and them to be compatible in any way requires a virtually parallel evolution (okay, so I wasn't [i]entirely[/] taking the p*** before) so improbable as to be just about impossible.
Resources? What have we got that the rest of the universe doesn't have? I'm not asking for speculation on why they're here, because that's necessarily a fruitless task. But instead, look at ourselves, and ask what makes us such a tourist hotspot? Especially for 57 different species (if you believe that)?
No, in all seriousness, I say we're nothing special in the Grand Order of Things, and for that reason, among others, it makes little sense for ET to come here.
IMO one reason people believe in the ETH is because it's comforting. We are special. Special enough for ET to spend time, energy, and resources to travel light years (even if they use the famed wormholes and it's virtually instantaneous, or interdimensional travel, or other methods which are at best theoretical to today's scientists) when they could make contact via radio waves, which is much cheaper and easier.
And if I'm right, and people believe because it's comforting (in one way or another), then not only will there never be enough proof to convince the believers otherwise (for instance, "We've searched for decades, but still haven't found any concrete evidence"), but any sort of logical proof is irrelevant. It's truly akin to arguing for and against the existence of God. There may be converts to one side or the other at times, but "proof" is nowhere to be found.
But both sides will always keep trying to convince the other. Not that there's anything wrong with that.