something from every kind of food
is cast out into the privy. It may also be said that whatever is
generated from food, can be dissolved by natural heat, and be cast
aside through the pores, as Jerome expounds the passage.

Reply Obj. 2: By flesh belonging to the species, some have understood
that which first receives the human species, which is derived from
the begetter: this, they say, lasts as long as the individual does.
By flesh belonging to the matter these understand what is generated
from food: and this, they say, does not always remain, but as it
comes so it goes. But this is contrary to the mind of Aristotle. For
he says there, that "just as in things which have their species in
matter"--for instance, wood or stone--"so in flesh, there is
something belonging to the species, and something belonging to
matter." Now it is clear that this distinction has no place in
inanimate things, which are not generated seminally, or nourished.
Again, since what is generated from food is united to, by mixing
with, the body so nourished, just as water is mixed with wine, as the
Philosopher says there by way of example: that which is added, and
that to which it is added, cannot be different natures, since they
are already made one by being mixed together. Therefore there is no
reason for saying that one is destroyed by natural heat, while the
other remains.

It must therefore be said that this distinction of the Philosopher is
not of different kinds of flesh, but of the same flesh considered
from different points of view. For if we consider the flesh according
to the species, that is, according to that which is formed therein,
thus it remains always: because the nature of flesh always remains
together with its natural disposition. But if we consider flesh
according to matter, then it does not remain, but is gradually
destroyed and renewed: thus in the fire of a furnace, the form of
fire remains, but the matter is gradually consumed, and other matter
is substituted in its place.

Reply Obj. 3: The "radical humor" is said to comprise whatever the
virtue of the species is founded on. If this be taken away it cannot
be renewed; as when a man's hand or foot is amputated. But the
"nutritive humor" is that which has not yet received perfectly the
specific nature, but is on the way thereto; such is the blood, and
the like. Wherefore if such be taken away, the virtue of the species
remains in its root, which is not destroyed.

Rep