Nicene and Post-Nicene Fathers, Vol. V:
A Treatise on the Soul and its Origin.: Chapter 18

Chapter 18.—The First Question, Whether the Soul is Corporeal; Breath and Wind, Nothing Else Than Air in Motion.

Now whether the soul is such a substance, is an extremely nice and subtle question. You, indeed, with a promptitude for which I very greatly congratulate you, affirm that God is not a body. But then, again, you give me some anxiety when you say, “If the soul lacks body, so as to be (as some persons are pleased to suppose) of hollow emptiness, of airy and futile substance.” Now, from these words you seem to believe, that everything which lacks body is of an empty substance. Well, if this is the case, how do you dare to say that God lacks body, without fearing the consequence that He is of an empty substance? If, however, God has not p. 362 a body, as you have just allowed; and if it be profane to say that He is of an empty substance; then not everything which lacks body is an empty substance. And therefore a person who contends that the soul is incorporeal does not necessarily mean, that it is of an empty and futile substance; for he allows that God, who is not an empty being, is at the same time incorporeal. But observe what great difference there is between my actual assertion, and what you suppose me to say. I do not say that the soul is an airy substance; if I did, I should admit that it is a body. For air is a body; as all who understand what they say declare, whenever they speak concerning bodily substances. But you, because I called the soul incorporeal, supposed me not only to predicate mere emptiness of it, but, as the result of such predication, to say that it is “an airy substance;” whereas I must have said both that it has not corporeity, which air has, and that what is filled with air could not be empty. And your own bag similes failed to remind you of this. For when the bags are inflated, what is it but air that is pressed into them? And they are so far from being empty, that by reason of their distension they become even ponderous. But perhaps the breath seems to you to be a different thing from air; although your very breath is nothing else than air in motion; and what this is, can be seen from the shaking of a fan. With respect to any hollow vessels, which you may suppose to be empty, you may ascertain with certainty that they are really full, by lowering them straight into the water, with the mouth downwards. You see no water can get in, by reason of the air with which they are filled. If, however, they are lowered either in the opposite way, with mouth upward, or aslant, they then fill, as the water enters at the same opening where the air passes out and escapes. This could be, of course, more easily proved by performing the experiment, than by a description in writing. This, however, is not the time or place for longer delay on the subject; for whatever may be your perception of the nature of the air, as to whether it has corporeity or not, you certainly ought not to suppose me to have said that the soul is an aerial thing, but absolutely incorporeal. And this even you acknowledge God to be, whom you do not dare to describe as an empty substance, while you cannot but admit that He has an essence which is unchangeable and almighty. Now, why should we fear that the soul is an empty void, if it be incorporeal, when we confess that God is incorporeal, and at the same time deny Him to be an empty void? Thus it was within the competency of an Incorporeal Being to create an incorporeal soul, even as the living God made living man; although, as the unchangeable and the almighty, He communicated not these attributes to the changeable and far inferior creature.