I would add knowledge and misconceptions here
Discussion
Truth and falsehoods, as well.
The larger point I am trying to make is that there are categories that things fall into. So, you can prove that something is the one, or at least tends strongly to the one, if it is clearly not the other.
It seems intuitive. But after all, the same thing can be located in different categories for different people with different points of view based on hereditary and acquired factors.
That people categorize it differently, doesn't negate the point that it there are only two categories. Which categorization is "more correct" has to be deliberated.
It's a rhetorical rule, like "the greater and the lesser".