The Categories

Part 8

By ‘quality’ I mean that in virtue of which people are said to be such
and such.

Quality is a term that is used in many senses. One sort of quality let
us call ‘habit’ or ‘disposition’. Habit differs from disposition in
being more lasting and more firmly established. The various kinds of
knowledge and of virtue are habits, for knowledge, even when acquired
only in a moderate degree, is, it is agreed, abiding in its character
and difficult to displace, unless some great mental upheaval takes
place, through disease or any such cause. The virtues, also, such as
justice, self-restraint, and so on, are not easily dislodged or
dismissed, so as to give place to vice.

By a disposition, on the other hand, we mean a condition that is easily
changed and quickly gives place to its opposite. Thus, heat, cold,
disease, health, and so on are dispositions. For a man is disposed in
one way or another with reference to these, but quickly changes,
becoming cold instead of warm, ill instead of well. So it is with all
other dispositions also, unless through lapse of time a disposition has
itself become inveterate and almost impossible to dislodge: in which
case we should perhaps go so far as to call it a habit.

It is evident that men incline to call those conditions habits which
are of a more or less permanent type and difficult to displace; for
those who are not retentive of knowledge, but volatile, are not said to
have such and such a ‘habit’ as regards knowledge, yet they are
disposed, we may say, either better or worse, towards knowledge. Thus
habit differs from disposition in this, that while the latter in
ephemeral, the former is permanent and difficult to alter.

Habits are at the same time dispositions, but dispositions are not
necessarily habits. For those who have some specific habit may be said
also, in virtue of that habit, to be thus or thus disposed; but those
who are disposed in some specific way have not in all cases the
corresponding habit.

Another sort of quality is that in virtue of which, for example, we
call men good boxers or runners, or healthy or sickly: in fact it
includes all those terms which refer to inborn capacity or incapacity.
Such things are not predicated of a person in virtue of his
disposition, but in virtue of his inborn capacity or incapacity to do
something with ease or to avoid defeat of any kind. Persons are called
good boxers or good runners, not in virtue of such and such a
disposition, but in virtue of an inborn capacity to accomplish
something with ease. Men are called healthy in virtue of the inborn
capacity of easy resistance to those unhealthy influences that may
ordinarily arise; unhealthy, in virtue of the lack of this capacity.
Similarly with regard to softness and hardness. Hardness is predicated
of a thing because it has that capacity of resistance which enables it
to withstand disintegration; softness, again, is predicated of a thing
by reason of the lack of that capacity.

A third class within this category is that of affective qualities and
affections. Sweetness, bitterness, sourness, are examples of this sort
of quality, together with all that is akin to these; heat, moreover,
and cold, whiteness, and blackness are affective qualities. It is
evident that these are qualities, for those things that possess them
are themselves said to be such and such by reason of their presence.
Honey is called sweet because it contains sweetness; the body is called
white because it contains whiteness; and so in all other cases.

The term ‘affective quality’ is not used as indicating that those
things which admit these qualities are affected in any way. Honey is
not called sweet because it is affected in a specific way, nor is this
what is meant in any other instance. Similarly heat and cold are called
affective qualities, not because those things which admit them are
affected. What is meant is that these said qualities are capable of
producing an ‘affection’ in the way of perception. For sweetness has
the power of affecting the sense of taste; heat, that of touch; and so
it is with the rest of these qualities.

Whiteness and blackness, however, and the other colours, are not said
to be affective qualities in this sense, but because they themselves
are the results of an affection. It is plain that many changes of
colour take place because of affections. When a man is ashamed, he
blushes; when he is afraid, he becomes pale, and so on. So true is
this, that when a man is by nature liable to such affections, arising
from some concomitance of elements in his constitution, it is a
probable inference that he has the corresponding complexion of skin.
For the same disposition of bodily elements, which in the former
instance was momentarily present in the case of an access of shame,
might be a result of a man’s natural temperament, so as to produce the
corresponding colouring also as a natural characteristic. All
conditions, therefore, of this kind, if caused by certain permanent and
lasting affections, are called affective qualities. For pallor and
duskiness of complexion are called qualities, inasmuch as we are said
to be such and such in virtue of them, not only if they originate in
natural constitution, but also if they come about through long disease
or sunburn, and are difficult to remove, or indeed remain throughout
life. For in the same way we are said to be such and such because of

Those conditions, however, which arise from causes which may easily be
rendered ineffective or speedily removed, are called, not qualities,
but affections: for we are not said to be such in virtue of them. The man
who blushes through shame is not said to be a constitutional blusher,
nor is the man who becomes pale through fear said to be
constitutionally pale. He is said rather to have been affected.

Thus such conditions are called affections, not qualities. In like
manner there are affective qualities and affections of the soul. That
temper with which a man is born and which has its origin in certain
deep-seated affections is called a quality. I mean such conditions as
insanity, irascibility, 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

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

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 both 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 a
quality. This will be evident from particular instances, if we apply
the names used to denote the other categories; for instance, granted
that justice is the contrary of injustice and justice is a quality,
injustice will also be a quality: neither quantity, nor relation, nor
place, nor indeed any other category but that of quality, will be
applicable properly to injustice. So it is with all other contraries
falling under the category of quality.

Qualities admit of variation of degree. Whiteness is predicated of one
thing in a greater or less degree than of another. This is also the
case with reference to justice. Moreover, one and the same thing may
exhibit a quality in a greater degree than it did before: if a thing is
white, it may become whiter.

Though this is generally the case, there are exceptions. For if we
should say that justice admitted of variation of degree, difficulties
might ensue, and this is true with regard to all those qualities which
are dispositions. There are some, indeed, who dispute the possibility
of variation here. They maintain that justice and health cannot very
well admit of variation of degree themselves, but that people vary in
the degree in which they possess these qualities, and that this is the
case with grammatical learning and all those qualities which are
classed as dispositions. However that may be, it is an incontrovertible
fact that the things which in virtue of these qualities are said to be
what they are vary in the degree in which they possess them; for one
man is said to be better versed in grammar, or more healthy or just,
than another, and so on.

The qualities expressed by the terms ‘triangular’ and ‘quadrangular’ do
not appear to admit of variation of degree, nor indeed do any that have
to do with figure. For those things to which the definition of the
triangle or circle is applicable are all equally triangular or
circular. Those, on the other hand, to which the same definition is not
applicable, cannot be said to differ from one another in degree; the
square is no more a circle than the rectangle, for to neither is the
definition of the circle appropriate. In short, if the definition of
the term proposed is not applicable to both objects, they cannot be
compared. Thus it is not all qualities which admit of variation of

Whereas none of the characteristics I have mentioned are peculiar to
quality, the fact that likeness and unlikeness can be predicated with
reference to quality only, gives to that category its distinctive
feature. One thing is like another only with reference to that in
virtue of which it is such and such; thus this forms the peculiar mark
of quality.

We must not be disturbed because it may be argued that, though
proposing to discuss the category of quality, we have included in it
many relative terms. We did say that habits and dispositions were
relative. In practically all such cases the genus is relative, the
individual not. Thus knowledge, as a genus, is explained 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.