Enneads IV.7: Of the Immortality of the Soul: Polemic Against Materialism
There Is No Conceivable Way in Which Soul Could Perish
12. (17). (The Stoics), indeed, claim that every soul is perishable. In this case, everything should long since have been destroyed. Others might say that our soul were mortal, while the universal Soul were immortal. On them, however, is the burden of proof of a difference between the individual and universal souls. Both of them, indeed, are a principle of movement; both live by themselves; both grasp the same object by the same faculty, either by thinking the things contained in heaven, or by considering the nature (“being”) of each being, ascending unto the first principle. Since our soul thinks absolute essences either by the notions she finds within herself, or by reminiscence, she evidently is prior to the body. Possessing knowledge of eternal entities, she herself must be eternal. All that dissolves, existing only by its compositeness, can naturally dissolve in the same manner that it became composite. But the soul is a single, simple actualization, whose essence is life; not in this manner therefore can the soul perish. Neither could the soul perish by division into a number of parts; for, as we have shown, the soul is neither a mass nor a quantity. As little could the soul perish by alteration; for when alteration destroys anything, it may remove its form, but leaves its matter; alteration, therefore, is a characteristic of something composite. Consequently as the soul cannot perish in any of these ways, she is imperishable.
DESCENT INTO THE BODY NEED NOT CONFLICT WITH THE ETERNITY OF SOUL.
13. (18). If intelligible entities are separated from sense objects, how does it happen that the soul descends into a body? So long as the soul is a pure and impassible intelligence, so long as she enjoys a purely intellectual life like the other intelligible beings, she dwells among them; for she has neither appetite nor desire. But that part which is inferior to intelligence and which is capable of desires, follows their impulsion, “proceeds” and withdraws from the intelligible world. Wishing to ornament matter on the model of the Ideas she contemplated in Intelligence, in haste to exhibit her fruitfulness, and to manifest the germs she bears within her (as said Plato, in the Banquet), the soul applies herself to produce and create, and, as result of this application, she is, as it were, orientated (or, in “tension”) towards sense-objects. With the universal Soul, the human soul shares the administration of the whole world, without, however, entering it; then, desiring to administer some portion of the world on her own responsibility, she separates from the universal Soul, and passes into a body. But even when she is present with the body, the soul does not devote herself entirely to it, as some part of her always remains outside of it; that is how her intelligence remains impassible.