I have doubts about the existential import in categorial propositions of the form "No A is B" under Aristotelian interpretation. In "No A is B", it is assumed that both A and B are not empty, right?
However when I take a look at the "No A is B" Venn diagram in the square of opposition diagram from Wikipedia, it tells me that in "No A is B", only A is guaranteed to be nonempty and we don't know whether B is empty or not. I think this interpretation is wrong because "No A is B" is logically equivalent to its converse "No B is A" so both A and B should be nonempty. In other words, the correct Venn diagram for "No A is B" should be something like
Am I wrong?
