Peter of Auvergne on Substance

Contemporary interpreters of Aristotle’s ‘Metaphysics’, book Z, have addressed a special attention to the problem of the continuity vs. discontinuity of the "Metaphysics" doctrine of substance with respect to that of the "Categories". In the "Categories" Aristotle characterizes a 'primary substance' as that which is neither predicable of a subject nor in a subject, but of which any other thing is predicated. In the "Categories" this characterization of substance leads Aristotle to identify primary substances with the individual objects of the common experience, viz. with whatever can be designated by means of a linguistic demonstrative conjoined with a common noun, for example ‘this man’ or ‘this table’. In the "Metaphysics" the reference of this phrase undoubtdly changes, for Aristotle calls 'primary substance' the substantial form of an object of the common experience. The paper reconstructs Peter of Auvergne's position on this apparent conflict and, more generally, his doctrine of substance.