It will suffice to oppose the arguments of Ammonius, teacher of
Plotinos, and those of Numenius the Pythagorean, to that of all those
who claim that the soul is material. These are the reasons: "Bodies,
containing nothing unchangeable, are naturally subject to change, to
dissolution, and to infinite divisions. They inevitably need some
principle that may contain them, that may bind and strengthen their
parts; this is the unifying principle that we call soul. But if the
soul also be material, however subtle be the matter of which she may be
composed, what could contain the soul herself, since we have just seen
that all matter needs some principle to contain it? The same process
will go on continuously to infinity until we arrive at an immaterial
substance."