There's a term for this, sort of like a scientific equivalent of cultural relativism. The problem with proof is that the existence of something exists independently of people's ability to find proof of it's existence. Similarly, there's plenty of times where scientists had completely wrong interpretations of the universe based on spurious information available to them at the time.
I think though that you can read into this sort of stuff too much. For example, our current model of physics is quite flawed in that it has too completely separate sets of rules for things that occur on a quantum level, and... everything else, and has nothing to reconcile them. It's likely, even within our lifetimes that a completely profound discovery will render everything currently known about science to be completely wrong. But I very much believe that it's better to be wrong for the right reason than right for the wrong one... So we teach stuff like this which will be laughed at sooner or later because it's the best we have now given the information. If we got too caught up in objectivity and saying "ah, but we can never be sure if this is really right or not", we'd never advance because things like science are largely based on people making completely wrong assumptions that get progressively less wrong as time goes on because we learn from our mistakes.
