Book 1, Chapter 3, Footnote #01
A point about Aristotle and the categories
On the preceding passage Professor Bain remarks (Logic, i. 265): ``The Categories do not seem to have been intended as a classification of Nameable Things, in the sense of `an enumeration of all kinds of Things which are capable of being made predicates, or of having anything predicated of them'. They seem to have been rather intended as a generalization of predicates; an analysis of the final import of predication. Viewed in this light, they are not open to the objections offered by Mr. Mill. The proper question to ask is not---In what Category are we to place sensations or other feelings or states of mind? but, Under what Categories can we predicate regarding states of mind? Take, for example, Hope. When we say that it to a state of mind, we predicate Substance: we may also describe how great it Is (Quantity), what is the quality of it, pleasurable or painful (Quality), what it has reference to (Relation). Aristotle seems to have framed the Categories on the plan---Here is an individual; what is the final analysis of all that we can predicate about him?''
This is doubtless a true statement of the leading idea in the classification. The Category Ousía was certainly understood by Aristotle to be a general name for all possible answers to the questions Quid sit? when asked respecting a concrete individual; as the other Categories are names comprehending all possible answers to the questions Quantum sit? Quale sit? &c. In Aristotle's conception, therefore, the Categories may not have been a classification of Things; but they were soon converted into one by his scholastic followers, who certainly regarded and treated them as a classification of Things, and carried them out as such, dividing down the Category Substance as a naturalist might do, into the different classes of physical or metaphysical objects as distinguished from attributes, and the other Categories into the principal varieties of quantity, quality, relation, &c. It is, therefore, a just subject of complaint against them, that they had no Category of Feeling. Feeling is assuredly predicable as a summum genus, of every particular kind of feeling, for instance, as in Mr. Bain's example, of Hope: but it cannot be brought within any of the Categories as interpreted either by Aristotle or by his followers.