The Complete Aristotle (eng.)

by
reference to something else, for we mean a knowledge of something.
But particular branches of knowledge are not thus explained. The
knowledge of grammar is not relative to anything external, nor is
the knowledge of music, but these, if relative at all, are relative
only in virtue of their genera; thus grammar is said be the
knowledge of something, not the grammar of something; similarly
music is the knowledge of something, not the music of
something.
    Thus individual branches of knowledge are not relative. And it
is because we possess these individual branches of knowledge that
we are said to be such and such. It is these that we actually
possess: we are called experts because we possess knowledge in some
particular branch. Those particular branches, therefore, of
knowledge, in virtue of which we are sometimes said to be such and
such, are themselves qualities, and are not relative. Further, if
anything should happen to fall within both the category of quality
and that of relation, there would be nothing extraordinary in
classing it under both these heads.
9
    Action and affection both admit of contraries and also of
variation of degree. Heating is the contrary of cooling, being
heated of being cooled, being glad of being vexed. Thus they admit
of contraries. They also admit of variation of degree: for it is
possible to heat in a greater or less degree; also to be heated in
a greater or less degree. Thus action and affection also admit of
variation of degree. So much, then, is stated with regard to these
categories.
    We spoke, moreover, of the category of position when we were
dealing with that of relation, and stated that such terms derived
their names from those of the corresponding attitudes.
    As for the rest, time, place, state, since they are easily
intelligible, I say no more about them than was said at the
beginning, that in the category of state are included such states
as ‘shod’, ‘armed’, in that of place ‘in the Lyceum’ and so on, as
was explained before.
10
    The proposed categories have, then, been adequately dealt
with.
    We must next explain the various senses in which the term
‘opposite’ is used. Things are said to be opposed in four senses:
(i) as correlatives to one another, (ii) as contraries to one
another, (iii) as privatives to positives, (iv) as affirmatives to
negatives.
    Let me sketch my meaning in outline. An instance of the use of
the word ‘opposite’ with reference to correlatives is afforded by
the expressions ‘double’ and ‘half’; with reference to contraries
by ‘bad’ and ‘good’. Opposites in the sense of ‘privatives’ and
‘positives’ are’ blindness’ and ‘sight’; in the sense of
affirmatives and negatives, the propositions ‘he sits’, ‘he does
not sit’.
    (i) Pairs of opposites which fall under the category of relation
are explained by a reference of the one to the other, the reference
being indicated by the preposition ‘of’ or by some other
preposition. Thus, double is a relative term, for that which is
double is explained as the double of something. Knowledge, again,
is the opposite of the thing known, in the same sense; and the
thing known also is explained by its relation to its opposite,
knowledge. For the thing known is explained as that which is known
by something, that is, by knowledge. Such things, then, as are
opposite the one to the other in the sense of being correlatives
are explained by a reference of the one to the other.
    (ii) Pairs of opposites which are contraries are not in any way
interdependent, but are contrary the one to the other. The good is
not spoken of as the good of the had, but as the contrary of the
bad, nor is white spoken of as the white of the black, but as the
contrary of the black. These two types of opposition are therefore
distinct. Those contraries which are such that the subjects in
which they are naturally present, or of which they are predicated,
must necessarily contain either the one or the other of them, have
no intermediate, but those in the case of which no such necessity
obtains, always have an intermediate. Thus disease and health are
naturally present in the body of an animal, and it is necessary
that either the one or the other should be present in the body of
an animal. Odd and even, again, are predicated of number, and it is
necessary that the one or the other should be present in numbers.
Now there is no intermediate between the terms of either of these
two pairs. On the other