On the Immortality of the Soul

[...sur]viving, it cannot be a part when a part is corrupted; and for that reason they wish the whole itself to be abolished, and they think it to be so one with the body in the very constitution of man that they judge if one be separated from the other, that very thing which is "to be a man" perishes entirely; and thus they either place it in the number of natural forms, so that they wish it proved by natural reason that the soul is immaterial only by participation; or they do not hesitate to contend that this opinion is at least more probable than that by which immortality is accustomed to be asserted. These things, and if they scatter anything of this kind, so that they establish the intellect by which the soul itself understands as either entirely mortal with Alexander, or with Averroes

Against those very reasons asserting mortality, which will afterwards be dissolved.

as one in all men—neither of these, nor of such views, has ever seemed to me worthy to be decreed by a man excelling in both genius and learning. For it is necessary that those who speak thus either know or remember that such are the properties of the human soul that lower things cannot be compared to it. She herself, being incorruptible, informs the corruptible body and survives the body, as will be broadly evident in what follows; and for that reason she performs certain functions both with the body and without the body. She has something in common with plants, with brutes, and with higher minds. But this is especially proper to her: that in whatever way she participates in what the others participate, nothing is so entirely similar to her. Those who have noticed this less than is fitting have ascribed to her a certain communion, and have snatched one part this way and another part that way. But it ought not to be so. For it was necessary to perceive in the mind and weigh the parts and their specific nature separately, and separately that which is composed of those parts; and they could easily have been reminded of this matter even from Aristotle himself. For if he himself in the Metaphysics said that a syllable composed of a and b is not a and b, but ab—that is, that the composite itself is not the extremes—how much more in the composition of a mortal and immortal nature ought the property of each part, and of that which is composed of them, to be weighed? And from here it is also possible to notice that neither the division of mortality nor of immortality, which some have attempted to assert, satisfies either simply or in any way the declaration of the nature of the soul. For those properties of the soul which leap out from these must be sought and grasped: which we shall strive for to the best of our ability in this very digression. Certainly the human soul, joined to the body, has a bond of higher and in-