 Aristotle acknowledges that there are three candidates for being called substance, and that all three are substance in some sense or to some degree. First, there is matter, second, form and third, the composite of form and matter. Aristotle acknowledges that matter can be a subject of predication and of change, thereby meeting one of the main criteria set up in Categories (1028 b35ff). This suggests an inadequacy or incompleteness in the account in Categories, for there he had seemed to assume that being the subject of predication belonged peculiarly to substance, and also that a subject is an individual of an appropriate kind—what he calls a ‘this such’: and matter is not an individual, but that from which an individual is made. Two of the criteria of substancehood presented in the Introduction above are: (v) being individuals and kinds of individual; (vi) being stuffs and kinds of stuff. Aristotle acknowledges that things under (vi)—‘natural bodies such as fire and water and everything of that sort’ (1028 b10–11)—are, or are thought to be, substances. But, without seeming to give much argument, he strongly favours (v) over (vi).