EXISTENCE AND NON-EXISTENCE

Now, suppose we have two categories, A and B, and we are told simply that “There are some A.” If we are told nothing about whether these individuals are or are not B, we will not know whether to put the x in the top left square (AB) or the top right.

Similarly, if we were told that “There are some B,” this would be represented:

Now, suppose we have the same two categories, A and B, and we are told simply that “There are no A.” This requires us to put a 0 in two regions: the top left square (AB) and the top right

15.2.3