Animal is SAID OF man. Color is SAID OF white. IN a subject This is a relation of fundamental ontological dependence . This grammatical knowledge is IN a soul. This white is IN a body.
Color is IN body.
Although Aristotle does not use these terms in the Categories , it is clear that he intends to capture the notions of universal and particular with his SAID OF locution. So a universal is what is SAID OF some subject, and a particular is what is not SAID OF any subject. White and color are universal qualities. That is, everything other than primary substance is either SAID OF or IN primary substances. Therefore, if primary substances did not exist, neither would anything else.