4. (f) (If the soul is anything but simple matter, she must be
constituted by a substantial form.) Those who claim that the soul
is a body are, by the very force of the truth, forced to recognize
the existence, before and above them, of a form proper to the soul;
for they acknowledge the existence of an intelligent spirit, and an
intellectual fire (as do the Stoics, following in the footsteps of
Heraclitus, Stobaeus[49]). According to them, it seems that, without
spirit or fire, there cannot be any superior nature in the order of
beings, and that the soul needs a location where she may be built
up. On the contrary, it is bodies alone that need to be built up on
something, and indeed, they are founded on the powers of the soul.
If really we do believe that the soul and life are no more than a
spirit, why add the qualification "of a certain characteristic,"[50]
a meaningless term employed when forced to admit an active nature
superior to that of bodies. As there are thousands of inanimate
spirits, not every spirit is a soul. If only that spirit is a
soul which possesses that "special characteristic," this "special
characteristic" and this "manner of being" will either be something
real, or will be nothing. If they are nothing, there will be nothing
real but spirit, and this alleged "manner of being" is nothing more
than a word. In that system, therefore, nothing but matter really
exists. God, the soul, and all other things are no more than a word;
the body alone really subsists. If, on the contrary, that "manner of
being" is something real, if it is anything else than substrate or
matter, if it resides in matter without being material or composed of
matter, it must then be a nature different from the body, namely, a
reason (by a pun).[51]