Si consideremus habitum secundum ea ad quae se extendit, sic inveniemus in eo quandam multiplicitatem, sed quia illa multiplicitas est ordinata ad aliquid unum, ad quod principaliter respicit habitus, inde est quod habitus est qualitas simplex, non constituta ex pluribus habitibus, etiam si ad multa se extendat, quia non unus habitus se extendit ad multa, nisi in ordine ad unum, ex quo habet unitatem.
If we consider a habit as to the extent of its object, we shall find a certain multiplicity therein; but since this multiplicity is directed to one thing, on which the habit is chiefly intent, hence it is that a habit is a simple quality, not composed from several habits, even though it extend to many things, because a habit does not extend to many things save in relation to one, whence it derives its unity.
Ille qui in aliqua scientia acquirit per demonstrationem scientiam conclusionis unius, habet quidem habitum, sed imperfecte. Cum vero acquirit per aliquam demonstrationem scientiam conclusionis alterius, non aggeneratur in eo alius habitus; sed habitus qui prius inerat fit perfectior, utpote ad plura se extendens; eo quod conclusiones et demonstrationes unius scientiae ordinatae sunt, et una derivatur ex alia.
In any science, he who acquires, by demonstration, scientific knowledge of one conclusion, has the habit indeed, yet imperfectly. And when he obtains, by demonstration, the scientific knowledge of another conclusion, no additional habit is engendered in him: but the habit which was in him previously is perfected, inasmuch as it has increased in extent; because the conclusions and demonstrations of one science are coordinate, and one flows from another.