" "You never know what you'll find if you start looking without prejudice."

Except that 'prejudice' may not be exactly the right word. Many who 'look' in certain directions already have a 'predisposition' to interpret genuine experiences as metaphysical or religious...etc.
   The extreme of this is crowds wanting to believe they see an image of Jesus on a rusty water tank. If a person who already has an opinion... or predisposition... to the OOB or such like has an intense experience, well.... the word 'proof' in the thread title is almost always overused & inappropriate.