"But if there is no definitive evidence against it, then in order to investigate a matter one must believe in the possibility; otherwise, there would be no scientific experiments done on anything. One can hypothesize without evidence in order to seek evidence-- for or against."

This is a difficult claim to examine. It IS true and logical...as it stands, but I think there is an unstated premise..perhaps even what is called "undistributed middle" embedded in it.
   Since we are dealing with religious and (obliquely) paranormal beliefs in this thread, it must be assumed that the assertion is being made that "hypothesizing without evidence" can be applied to them, just as we do in science at times. (There are all sorts of hypotheses about "missing matter" in the universe, and where it may 'be'. We have VERY little 'evidence' for some of the ideas being explored.)
   But with religious & paranormal claims & beliefs, the very concept of what might constitute evidence alters. Here we allow hearsay (reports of , historical & cultural 'data', psychological & emotional content (some of which includes supposed historical data), and equivocation on the definition OF evidence to count towards confidence in beliefs.

   I think it is a mistake to confuse the scientific method with what we do when exploring religious tenets. In other discussions, some of those who do hold strong religious beliefs have stated that they 'feel' the value and truth of their positions despite the seeming conflicts with the narrow restriction of the scientific method....and I would suggest that this is the way it must remain.

   *IF* there is truth to religious claims and beliefs, it, by definition, is not subject to 'testing' in the same way a theory of 'dark matter' is. (They are building a new telescope that they think will reveal some traces of part of the missing matter.) No one seems to be able to even suggest what a 'test' for God might be, except waiting till after death, and seeing what happens.

   It is true that NO ONE can DISprove God..etc..(or Vishnu, or Ahura Mazda, or...etc..)...but we simply have different notions of how to interpret either the freedom, or the obligations that this gives us.

Whether we accept some religious doctrine or not, all we can do is explain OUR subjective rationale for our decision.
The crucial thing for BOTH sides is how we deal with the everyday, pragmatic decision of how to interact with each other and make integrating our differences as smooth and comfortable as possible. We are not about to legislate that people should not have religious faith....we should not, and could not if some of us we wanted to. But we do need to guard against that vocal minority who would legislate the other way. As long as there ARE 2 sides to this issue, we MUST coexist as peacefully as possible.

(27 sub paragraphs about specific details omitted to spare my fingers and to give this any chance of being read)