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] THE BODY EXERTS A UNIFORM ACTION, WHILE THE SOUL EXERTS A VARIED ONE. (g.) (The body exerts an uniform action, while the soul exerts a very diverse action.) The following considerations further demonstrate the impossibility of the soul being a body. A body must be hot or cold, hard or soft, liquid or solid, black or white, or qualities differing according to its nature. If it is only hot or cold, light or heavy, black or white, it communicates its only quality to what comes close to it; for fire could not cool, nor ice heat. Nevertheless, the soul produces not only different effects in different animals, but contrary effects even in the same being; she makes certain things solid, dense, black, light, and certain others liquid, sparse, white, or heavy. According to the different quality of the body, and according to its color, she should produce but a single effect; nevertheless, she exerts a very diverse action. THREE MORE PROOFS OF THE INCORPOREITY OF THE SOUL.