Chapter 10

The sense in which the soul can be considered as a mixed substance,
comprising principle and term

846. We said that the soul can be considered as term of some preceding action (of the Creator). This needs some explanation.
To say that the soul is term of some action prior to itself is one thing; it is another to say that this action situated and acting in its term is the soul. The second affirmation is obviously mistaken. First, it is absurd because it would follow that the soul would be the creative action; second, its absurdity can be proved directly (as it should be philosophically) by comparing our perception of soul with that of matter.

Bodies are perceived as direct effects of a foreign action in the soul. Because the concept of bodies results from their action in some other perceived ens, they are perceived in so far as their activity is in its term, in the passivities proper to the soul. But this activity of bodies in the soul as in their term is not the principle, unperceived by us, that makes them subsist as entia in themselves. The soul, on the contrary, is never perceived as acting in another ens different from itself, but as existing in itself. It is perceived, therefore, whole and entire even in the principle of its activity. The action of which it is term is something foreign to the principle called soul, and anterior to it. That which is principle of an act cannot be term of the same act, but of some preceding act.

The concept of the soul is that of principle. It is not term relative to its first (substantial) act, but term relative to another act different from itself which is not perceived.