  In the second kind of fundamental predication, the predicate indicates inherence in a subject. According to Aquinas, this kind of predication is initially divided into absolute (per se et absolute) and relative (in respectu ad aliud). In absolute predication the inherence comes from either the subject's matter or form. When it comes from the matter, then the predicate falls into the second category, quantity [quantitas]. For example, in ‘Socrates is five and a half feet tall,’ ‘five and a half feet tall’ is taken from Socrates' matter. But when the inherence comes from the form, the predicate falls into the third category, quality [qualitas]. For example, in ‘Socrates is rational,’ ‘rational’ is taken from the form of Socrates, his humanity. If the predication is relative, however, then the predicate falls into the fourth category, relation [ad aliud]. For example, in ‘Socrates is the father of philosophy,’ ‘father’ indicates the relation of Socrates to philosophy.