body perceived and a body in which perception takes place. Now if
that which is perceptible is annihilated, it follows that the
body is annihilated, for the body is a perceptible thing; and if
the body does not exist, it follows that perception also ceases
to exist. Thus the annihilation of the perceptible involves that
of perception.

But the annihilation of perception does not involve that of the
perceptible. For if the animal is annihilated, it follows that
perception also is annihilated, 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,