Editing Substance theory (section)

===Aristotle<!--'Primary substance', 'Primary substances', 'Secondary substance' and 'Secondary substances' redirect here-->===
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[[Aristotle]] used the term "substance" ({{langx|el|οὐσία}} ''[[ousia]]'') in a secondary sense for [[genus|genera]] and [[species]] understood as [[hylomorphism|hylomorphic forms]]. Primarily, however, he used it with regard to his [[Categories (Aristotle)|category]] of substance, the specimen ("this person" or "this horse") or [[identity (philosophy)|individual]], ''qua'' individual, who survives [[accident (philosophy)|accidental change]] and in whom the [[essence|essential properties]] inhere that define those [[problem of universals|universals]].{{quote|A substance—that which is called a substance most strictly, primarily, and most of all—is that which is neither said of a subject nor in a subject, e.g. the individual man or the individual horse. The species in which the things primarily called substances are, are called secondary substances, as also are the genera of these species. For example, the individual man belongs in a species, man, and animal is a genus of the species; so these—both man and animal—are called secondary substances.<ref name="Ackrill1988">{{cite book |first=J.L. |last=Ackrill |year=1988 |title=A New Aristotle Reader |publisher=Princeton University Press |isbn=9781400835829 |url=https://books.google.com/books?id=Cz8-DgxETuAC&pg=PA7 |page=7}}</ref>|Aristotle|''[[Categories (Aristotle)|Categories]]'' 2a13 (trans. [[J. L. Ackrill]])}}

In chapter 6 of book I the ''[[Physics (Aristotle)|Physics]]'' Aristotle argues that any change must be analysed in reference to the property of an invariant subject: as it was before the change and thereafter. Thus, in his hylomorphic account of change, ''matter'' serves as a relative substratum of transformation, i.e., of changing (substantial) form. In the ''Categories'', properties are predicated only of substance, but in chapter 7 of book I of the ''Physics'', Aristotle discusses substances coming to be and passing away in the "unqualified sense" wherein '''primary substances'''<!--boldface per WP:R#PLA--> (πρῶται οὐσίαι; ''Categories'' 2a35) are generated from (or perish into) a material substratum by having gained (or lost) the essential property that formally defines substances of that kind (in the secondary sense). Examples of such a substantial change include not only conception and dying, but also metabolism, e.g., the bread a man eats becomes the man. On the other hand, in [[accident (philosophy)|accidental]] change, because the essential property remains unchanged, by identifying the substance with its formal essence, substance may thereby serve as the relative subject matter or property-bearer of change in a qualified sense (i.e., barring matters of life or death). An example of this sort of accidental change is a change of color or size: a tomato becomes red, or a juvenile horse grows.

Aristotle thinks that in addition to primary substances (which are particulars), there are '''secondary substances'''<!--boldface per WP:R#PLA--> (δεύτεραι οὐσίαι), which are universals (''Categories'' 2a11–a18).<ref>{{Cite book|url=https://plato.stanford.edu/archives/fall2018/entries/aristotle-categories/|title=Aristotle's Categories|first=Paul|last=Studtmann|editor-first=Edward N.|editor-last=Zalta|date=January 9, 2018|publisher=Metaphysics Research Lab, Stanford University|via=Stanford Encyclopedia of Philosophy}}</ref>

However, according to [[Aristotelian view of God|Aristotle's theology]], a form of invariant form exists without matter, beyond the [[cosmos]], powerless and oblivious, in the eternal substance of the [[unmoved movers]].