 The bulk of the remaining discussion, which is known as the Post-Predicamenta, is directed at concepts involving some kind of opposition, the concepts of priority, posteriorty, simultaneity, and change. Although the latter part of the Categories is interesting, it is not clear that it is integral to either of Aristotle’s classificatory schemes. Moreover, his discussion there is largely superseded by his discussion of the same concepts in the Metaphysics. Hence, instead of discussing the Post-Predicamenta in detail, I shall at this point turn to a topic about Aristotle’s categories that is of fundamental philosophical and interpretive interest: how did Aristotle arrive at his list of categories?