We shall now explain the difference obtaining between a part and a faculty of the soul. One part differs from another by the characteristics of its genus (or, kind); while different faculties may relate to a common genus. That is why Aristotle did not allow that the soul contained parts, though granting that it contained faculties. Indeed, the introduction of a new part changes the nature of the subject, while the diversity of faculties does not alter its unity. Longinus did not allow in the animal (or, living being) for several parts, but only for several faculties.
Cassius Longinus (ca. 213–273 AD) foi um retórico helênico e crítico filósofo.
Numenius, who teaches that the faculty of assent (or, combining faculty) is capable of producing various operations, says that representation (fancy) is an accessory of this faculty, that it does not, however, constitute either an operation or function of it, but a consequence of it. The Stoics, on the contrary, not only make sensation consist in representation, but even reduce representation to (combining) assent. According to them sense-imagination (or sense-fancy) is assent, or the sensation of the determination of assent. Longinus, however, does not acknowledge any faculty of assent.