Whether the intellect is a power of the soul?

Objections

Objection 1 : It would seem that the intellect is not a power of the soul, but the essence of the soul. For the intellect seems to be the same as the mind. Now the mind is not a power of the soul, but the essence; for Augustine says (De Trin. ix, 2): "Mind and spirit are not relative things, but denominate the essence." Therefore the intellect is the essence of the soul.
Objection 2 : Further, different genera of the soul's powers are not united in some one power, but only in the essence of the soul. Now the appetitive and the intellectual are different genera of the soul's powers as the Philosopher says (De Anima ii, 3), but they are united in the mind, for Augustine (De Trin. x, 11) places the intelligence and will in the mind. Therefore the mind and intellect of man is of the very essence of the soul and not a power thereof.
Objection 3 : Further, according to Gregory, in a homily for the Ascension (xxix in Ev.), "man understands with the angels." But angels are called "minds" and "intellects." Therefore the mind and intellect of man are not a power of the soul, but the soul itself.
Objection 4 : Further, a substance is intellectual by the fact that it is immaterial. But the soul is immaterial through its essence. Therefore it seems that the soul must be intellectual through its essence.