And if this is so, they should already be here. We fail to observe them. Hence the premise is flawed: there are no neighbors who are way ahead of us.
--Boris
That led to a discussion of the "non-interference" principle. They've seen us, find us hopelessly backward, and choose to leave us alone for a few millenia to see if we grow up and mature as a civilization.
No way to prove it either way, without venturing into the Von Daniken tin-foil theories, but there it is.
Congressman Billybob