[roundsquare]

All aspects of reality coincide with the way the physical world works.

I think observable is the keyword here... we happened to be able to observe enough that we can conclude that E = mc^2

As for your second point... I don't think I agree. The fact of the matter is that as humans, we are essentially unable to reason about how beings with a different set of senses would think. With respect to cosmology, we basically react to how light moves around and that forms the basis of our science (our other senses don't really come into the picture). Its very difficult to think about an intelligence based on some other source of information and impossible to know what sort of data would be present (since we don't have access to the information).