§ 313. A predicate is something which is stated of a subject.
§ 314. A predicable is something which can be stated of a subject.
§ 315. The Heads of Predicables are a classification of the various things which can be stated of a subject, viewed in their relation to it.
§ 316. The treatment of this topic, therefore, as it involves the relation of a predicate to a subject, manifestly falls under the second part of logic, which deals with the proposition. It is sometimes treated under the first part of logic, as though the heads of predicables were a classification of universal notions, i.e. common terms, in relation to one another, without reference to their place in the proposition.
§ 317. The heads of predicables are commonly reckoned as five, namely,
(1) Genus.
(2) Species.
(3) Difference.
(4) Property.
(5) Accident.