Hi.

I have a question for any UFO skeptics that may be here. What is the
rationale for considering UFOs an "extraordinary claim" for which the
probability of being true is so nearly zero that it's best not to do
any serious and deep scientific investigations, anyway? Is it because
the supposed lack of evidence? If so, then why believe in, say, string
theory, which by the way has absolutely NO evidence (or at best, very
little) to directly prove that it actually is true, unlike general
relativity and quantum mechanics (which it purports to unify)? Why is
that considered a more "likely" or "reasonable" avenue of inquiry as
opposed to UFOs despite the fact that there is very little if any
direct evidence to substantiate it?