Chapter 30

In this same way the pagan philosophers stated the difference between substance, and nature, by saying that substance was being in the strict sense, whereas nature was substance which had been made specific by essential differences so as to have, in addition to being in the strict sense, being in such a way, whether rational or irrational, mortal or immortal. In other words, we may say that, according to them, nature is that unchangeable and immutable principle and cause and virtue which has been implanted by the Creator in each species for its activity—in the angels, for thinking and for communicating their thoughts to one another without the medium of speech; in men, for thinking, reasoning, and for communicating their innermost thoughts to one another through the medium of speech; in the brute beasts, for the vital, the sentient, and the respiratory operations; in the plants, for the power of assimilating nourishment, of growing, and reproducing; in the stones, the capacity for being heated or cooled and for being moved from place to place by another, that is to say, the inanimate capacity. This they called nature, or the most specific species—as, for example, angel, man, horse, dog, ox, and the like. For these are more general than the individual substances and contain them, and in each one of the individual substances contained by them they exist complete and in the same manner. And so, the more particular they called hypostasis, and the more general, which contained the hypostases, they called nature, but existence in the strict sense they called oucnoc, or substance.

The holy Fathers paid no attention to the many inane controversies, and that which is common to and affirmed of several things, that is to say, the most specific species, they called substance, and nature, and form—as, for example, angel, man, horse, dog, and the like. For, indeed 'substance' is so called from its 'being'; and 'nature', is so called from its 'being'. But είναι and πεφυκέναι both mean the same thing. Form, also, and species mean the same thing as nature. However, the particular they called individual, and person, and hypostasis or individual substance—as, for example, would be Peter and Paul. Now, the hypostasis must have substance together with accidents, and it must subsist in itself and be found to be sensibly, that is, actually,