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and so on: for
people are said to be mad or irascible in virtue of these.
Similarly those abnormal psychic states which are not inborn, but
arise from the concomitance of certain other elements, and are
difficult to remove, or altogether permanent, are called qualities,
for in virtue of them men are said to be such and such.
    Those, however, which arise from causes easily rendered
ineffective are called affections, not qualities. Suppose that a
man is irritable when vexed: he is not even spoken of as a
bad-tempered man, when in such circumstances he loses his temper
somewhat, but rather is said to be affected. Such conditions are
therefore termed, not qualities, but affections.
    The fourth sort of quality is figure and the shape that belongs
to a thing; and besides this, straightness and curvedness and any
other qualities of this type; each of these defines a thing as
being such and such. Because it is triangular or quadrangular a
thing is said to have a specific character, or again because it is
straight or curved; in fact a thing’s shape in every case gives
rise to a qualification of it.
    Rarity and density, roughness and smoothness, seem to be terms
indicating quality: yet these, it would appear, really belong to a
class different from that of quality. For it is rather a certain
relative position of the parts composing the thing thus qualified
which, it appears, is indicated by each of these terms. A thing is
dense, owing to the fact that its parts are closely combined with
one another; rare, because there are interstices between the parts;
smooth, because its parts lie, so to speak, evenly; rough, because
some parts project beyond others.
    There may be other sorts of quality, but those that are most
properly so called have, we may safely say, been enumerated.
    These, then, are qualities, and the things that take their name
from them as derivatives, or are in some other way dependent on
them, are said to be qualified in some specific way. In most,
indeed in almost all cases, the name of that which is qualified is
derived from that of the quality. Thus the terms ‘whiteness’,
‘grammar’, ‘justice’, give us the adjectives ‘white’,
‘grammatical’, ‘just’, and so on.
    There are some cases, however, in which, as the quality under
consideration has no name, it is impossible that those possessed of
it should have a name that is derivative. For instance, the name
given to the runner or boxer, who is so called in virtue of an
inborn capacity, is not derived from that of any quality; for lob
those capacities have no name assigned to them. In this, the inborn
capacity is distinct from the science, with reference to which men
are called, e.g. boxers or wrestlers. Such a science is classed as
a disposition; it has a name, and is called ‘boxing’ or ‘wrestling’
as the case may be, and the name given to those disposed in this
way is derived from that of the science. Sometimes, even though a
name exists for the quality, that which takes its character from
the quality has a name that is not a derivative. For instance, the
upright man takes his character from the possession of the quality
of integrity, but the name given him is not derived from the word
‘integrity’. Yet this does not occur often.
    We may therefore state that those things are said to be
possessed of some specific quality which have a name derived from
that of the aforesaid quality, or which are in some other way
dependent on it.
    One quality may be the contrary of another; thus justice is the
contrary of injustice, whiteness of blackness, and so on. The
things, also, which are said to be such and such in virtue of these
qualities, may be contrary the one to the other; for that which is
unjust is contrary to that which is just, that which is white to
that which is black. This, however, is not always the case. Red,
yellow, and such colours, though qualities, have no contraries.
    If one of two contraries is a quality, the other will also be