Re: the saying " just because you don't know, doesnt mean no one else knows"
I've never met any of them. I have no preference for any of them, and a general objection to all these constructions, common though they may be. A fact means something, because doesn't. When I hear constructions like this I assume that there's an implied subject for the second clause: 'Just because ..., [that] doesn't mean ...'.
b