Also I should give an example. You'll have an event that most people agree is x and yet there will be plenty of self-appointed devil's advocates to protest the idea of it being x, being as pedantic as possible, teasing out minor details and ignoring every other instance of x just so they can proclaim this one as "coincidental."
If we all can't see a thing and agree what happened, agree there is a problem, we can't even get to the disagreement on how to deal with said problem.