nnihilated, but perceptibles such as body, heat,
sweetness, bitterness, and so on, will remain.

Again, perception is generated at the same time as the perceiving
subject, for it comes into existence at the same time as the animal.
But the perceptible surely exists before perception; for fire and water
and such elements, out of which the animal is itself composed, exist
before the animal is an animal at all, and before perception. Thus it
would seem that the perceptible exists before perception.

It may be questioned whether it is true that no substance is relative,
as seems to be the case, or whether exception is to be made in the case
of certain secondary substances. With regard to primary substances, it
is quite true that there is no such possibility, for neither wholes nor
parts of primary substances are relative. The individual man or ox is
not defined with reference to something external. Similarly with the
parts: a particular hand or head is not defined as a particular hand or
head of a particular person, but as the hand or head of a particular
person. It is true also, for the most part at least, in the case of
secondary substances; the species 'man' and the species 'ox' are not
defined with reference to anything outside themselves. Wood, again, is
only relative in so far as it is some one's property, not in so far as
it is wood. It is plain, then, that in the cases mentioned substance is
not relative. But with regard to some secondary substances there is a
difference of opinion; thus, such terms as 'head' and 'hand' are
defined with reference to that of which the things indicated are a
part, and so it comes about that these appear to have a relative
character. Indeed, if our definition of that which is relative was
complete, it is very difficult, if not impossible, to prove that no
substance is relative. If, however, our definition was not complete, if
those things only are properly called relative in the case of which
relation to an external object is a necessary condition of existence,
perhaps some explanation of the dilemma may be found.

The former definition does indeed apply to all relatives, but the fact
that a thing is explained with reference to something else does not
make it essentially relative.

From this it is plain that, if a man definitely apprehends a relative
thing, he will also definitely apprehend that to which it is relative.
Indeed this is self-evident: for if a man knows that some parti