Can we define religion as "the mythologies that don't assume they are mythologies"?
First, mythology is the oldest way of describing Nature. Polytheisms, extant or extinct, usually know|knew their mythologic nature. Thus the usually pacific and prolific relationships between many different polytheistic people (between many amerindian tribes, or between old indians and chinese, for instance).
Since many gods exist in such mythologies, for "my gods" to exist it isn't necessary that "your gods" don't exist.
Then monotheism comes to the picture. It claims to itself the status of "truth". For "my God", the "only god" to be correct, any other gods must be false. Isn't it a completely new concept? Isn't it a mythology, like any other, with the main difference of not accepting to be called like that? Doesn't it come wrapped in an unprecedented layer of lie (deny every other myth, except itself)? If so, how can we call all of them the same?
A: call both "mythology", and monotheism/religion a subset of all existing mythologies. B: call both "religion", but polytheism/mythology a subset of all existing religions.
Looks like the choice between A and B is entirely dependent of what you believe|think? Or is there a rational, concrete, least prone to doubt or attack, way of choosing?
Since polytheistic mythologies are much older and geographically more widespread, to me sounds natural that some modern so-called religions derived from them, and not the opposite (as some believers have already tried to convince me).
So, "religion" and "mythology" are synonyms? Or one is a subset of the other? If so, which is a subset of which?