by Aristotle
not for their being, but for their well-being. Such, e.g. is sight,
which, since it lives in air or water, or generally in what is
pellucid, it must have in order to see, and taste because of what is
pleasant or painful to it, in order that it may perceive these
qualities in its nutriment and so may desire to be set in motion,
and hearing that it may have communication made to it, and a tongue
that it may communicate with its fellows.
THE END
.
350 BC
TOPICS
by Aristotle
translated by W. A. Pickard-Cambridge
Book I
1
OUR treatise proposes to find a line of inquiry whereby we shall
be able to reason from opinions that are generally accepted about
every problem propounded to us, and also shall ourselves, when
standing up to an argument, avoid saying anything that will obstruct
us. First, then, we must say what reasoning is, and what its varieties
are, in order to grasp dialectical reasoning: for this is the object
of our search in the treatise before us.
Now reasoning is an argument in which, certain things being laid
down, something other than these necessarily comes about through them.
(a) It is a 'demonstration', when the premisses from which the
reasoning starts are true and primary, or are such that our
knowledge of them has originally come through premisses which are
primary and true: (b) reasoning, on the other hand, is
'dialectical', if it reasons from opinions that are generally
accepted. Things are 'true' and 'primary' which are believed on the
strength not of anything else but of themselves: for in regard to
the first principles of science it is improper to ask any further
for the why and wherefore of them; each of the first principles should
command belief in and by itself. On the other hand, those opinions are
'generally accepted' which are accepted by every one or by the
majority or by the philosophers-i.e. by all, or by the majority, or by
the most notable and illustrious of them. Again (c), reasoning is
'contentious' if it starts from opinions that seem to be generally
accepted, but are not really such, or again if it merely seems to
reason from opinions that are or seem to be generally accepted. For
not every opinion that seems to be generally accepted actually is
generally accepted. For in none of the opinions which we call
generally accepted is the illusion entirely on the surface, as happens
in the case of the principles of contentious arguments; for the nature
of the fallacy in these is obvious immediately, and as a rule even
to persons with little power of comprehension. So then, of the
contentious reasonings mentioned, the former really deserves to be
called 'reasoning' as well, but the other should be called
'contentious reasoning', but not 'reasoning', since it appears to
reason, but does not really do so. Further (d), besides all the
reasonings we have mentioned there are the mis-reasonings that start
from the premisses peculiar to the special sciences, as happens (for
example) in the case of geometry and her sister sciences. For this
form of reasoning appears to differ from the reasonings mentioned
above; the man who draws a false figure reasons from things that are
neither true and primary, nor yet generally accepted. For he does
not fall within the definition; he does not assume opinions that are
received either by every one or by the majority or by
philosophers-that is to say, by all, or by most, or by the most
illustrious of them-but he conducts his reasoning upon assumptions
which, though appropriate to the science in question, are not true;
for he effects his mis-reasoning either by describing the
semicircles wrongly or by drawing certain lines in a way in which they
could not be drawn.
The foregoing must stand for an outline survey of the species of
reasoning. In general, in regard both to all that we have already
discussed and to those which we shall discuss later, we may remark
that that amount of distinction between them may serve, because it
is not our purpose to give the exact definition of any of them; we
merely want to describe them in outline; we consider it quite enough
from the point of view of the line of inquiry before us to be able
to recognize each of them in some sort of way.
2
Next in order after the foregoing, we must say for how many and
for what purposes the treatise is useful. They are
three-intellectual training, casual encounters, and the
philosophical sciences. That it is useful as a training is obvious
on the face of it. The possession of a plan of inquiry will enable
us more easily to argue about the subject proposed. For purposes of
casual encounters, it is useful because when we have counted up the
opinions held by most people, we shall meet them on the ground not
of other people's convictions but of their own, while we shift the
ground of any argument that they appear to us to state unsoundly.
For the study of the philosophical sciences it is useful, because
the ability to raise searching difficulties on both sides of a subject
will make us detect more easily the truth and error about the
several points that arise. It has a further use in relation to the
ultimate bases of the principles used in the several sciences. For
it is impossible to discuss them at all from the principles proper
to the particular science in hand, seeing that the principles are
the prius of everything else: it is through the opinions generally
held on the particular points that these have to be discussed, and
this task belongs properly, or most appropriately, to dialectic: for
dialectic is a process of criticism wherein lies the path to the
principles of all inquiries.
3
We shall be in perfect possession of the way to proceed when we
are in a position like that which we occupy in regard to rhetoric
and medicine and faculties of that kind: this means the doing of
that which we choose with the materials that are available. For it
is not every method that the rhetorician will employ to persuade, or
the doctor to heal; still, if he omits none of the available means, we
shall say that his grasp of the science is adequate.
4
First, then, we must see of what parts our inquiry consists. Now
if we were to grasp (a) with reference to how many, and what kind
of, things arguments take place, and with what materials they start,
and (h) how we are to become well supplied with these, we should
have sufficiently won our goal. Now the materials with which arguments
start are equal in number, and are identical, with the subjects on
which reasonings take place. For arguments start with
'propositions', while the subjects on which reasonings take place
are 'problems'. Now every proposition and every problem indicates
either a genus or a peculiarity or an accident-for the differentia
too, applying as it does to a class (or genus), should be ranked
together
with the genus. Since, however, of what is peculiar to
anything part signifies its essence, while part does not, let us
divide the 'peculiar' into both the aforesaid parts, and call that
part which indicates the essence a 'definition', while of the
remainder let us adopt the terminology which is generally current
about these things, and speak of it as a 'property'. What we have
said, then, makes it clear that according to our present division, the
elements turn out to be four, all told, namely either property or
definition or genus or accident. Do not let any one suppose us to mean
that each of these enunciated by itself constitutes a proposition or
problem, but only that it is from these that both problems and
propositions are formed. The difference between a problem and a
proposition is a difference in the turn of the phrase. For if it be
put in this way, "'An animal that walks on two feet" is the definition
of man, is it not?' or '"Animal" is the genus of man, is it not?'
the result is a proposition: but if thus, 'Is "an animal that walks on
two feet" a definition of man or no?' [or 'Is "animal" his genus or
no?'] the result is a problem. Similarly too in other cases.
Naturally, then, problems and propositions are equal in number: for
out of every proposition you will make a problem if you change the
turn of the phrase.
5
We must now say what are 'definition', 'property', 'genus', and
'accident'. A 'definition' is a phrase signifying a thing's essence.
It is rendered in the form either of a phrase in lieu of a term, or of
a phrase in lieu of another phrase; for it is sometimes possible to
define the meaning of a phrase as well. People whose rendering
consists of a term only, try it as they may, clearly do not render the
definition of the thing in question, because a definition is always
a phrase of a certain kind. One may, however, use the word
'definitory' also of such a remark as 'The "becoming" is "beautiful"',
and likewise also of the question, 'Are sensation and knowledge the
same or different?', for argument about definitions is mostly
concerned with questions of sameness and difference. In a word we
may call 'definitory' everything that falls under the same branch of
inquiry as definitions; and that all the above-mentioned examples
are of this character is clear on the face of them. For if we are able
to argue that two things are the same or are different, we shall be
well supplied by the same turn of argument with lines of attack upon
their definitions as well: for when we have shown that they are not
the same we shall have demolished the definition. Observe, please,
that the converse of this last statement does not hold: for to show
that they are the same is not enough to establish a definition. To
show, however, that they are not the same is enough of itself to
overthrow it.
A 'property' is a predicate which does not indicate the essence of a
thing, but yet belongs to that thing alone, and is predicated
convertibly of it. Thus it is a property of man to-be-capable of
learning grammar: for if A be a man, then he is capable of learning
grammar, and if he be capable of learning grammar, he is a man. For no
one calls anything a 'property' which may possibly belong to something
else, e.g. 'sleep' in the case of man, even though at a certain time
it may happen to belong to him alone. That is to say, if any such
thing were actually to be called a property, it will be called not a
'property' absolutely, but a 'temporary' or a 'relative' property: for
'being on the right hand side' is a temporary property, while
'two-footed' is in point of fact ascribed as a property in certain
relations; e.g. it is a property of man relatively to a horse and a
dog. That nothing which may belong to anything else than A is a
convertible predicate of A is clear: for it does not necessarily
follow that if something is asleep it is a man.
A 'genus' is what is predicated in the category of essence of a
number of things exhibiting differences in kind. We should treat as
predicates in the category of essence all such things as it would be
appropriate to mention in reply to the question, 'What is the object
before you?'; as, for example, in the case of man, if asked that
question, it is appropriate to say 'He is an animal'. The question,
'Is one thing in the same genus as another or in a different one?'
is also a 'generic' question; for a question of that kind as well
falls under the same branch of inquiry as the genus: for having argued
that 'animal' is the genus of man, and likewise also of ox, we shall
have argued that they are in the same genus; whereas if we show that
it is the genus of the one but not of the other, we shall have
argued that these things are not in the same genus.
An 'accident' is (i) something which, though it is none of the
foregoing-i.e. neither a definition nor a property nor a genus yet
belongs to the thing: (something which may possibly either belong or
not belong to any one and the self-same thing, as (e.g.) the
'sitting posture' may belong or not belong to some self-same thing.
Likewise also 'whiteness', for there is nothing to prevent the same
thing being at one time white, and at another not white. Of the
definitions of accident the second is the better: for if he adopts the
first, any one is bound, if he is to understand it, to know already
what 'definition' and 'genus' and 'property' are, whereas the second
is sufficient of itself to tell us the essential meaning of the term
in question. To Accident are to be attached also all comparisons of
things together, when expressed in language that is drawn in any
kind of way from what happens (accidit) to be true of them; such as,
for example, the question, 'Is the honourable or the expedient
preferable?' and 'Is the life of virtue or the life of self-indulgence
the pleasanter?', and any other problem which may happen to be phrased
in terms like these. For in all such cases the question is 'to which
of the two does the predicate in question happen (accidit) to belong
more closely?' It is clear on the face of it that there is nothing
to prevent an accident from becoming a temporary or relative property.
Thus the sitting posture is an accident, but will be a temporary
property, whenever a man is the only person sitting, while if he be
not the only one sitting, it is still a property relatively to those
who are not sitting. So then, there is nothing to prevent an
accident from becoming both a relative and a temporary property; but a
property absolutely it will never be.
6
We must not fail to observe that all remarks made in criticism of
a 'property' and 'genus' and 'accident' will be applicable to
'definitions' as well. For when we have shown that the attribute in
question fails to belong only to the term defined, as we do also in
the case of a property, or that the genus rendered in the definition
is not the true genus, or that any of the things mentioned in the
p
hrase used does not belong, as would be remarked also in the case
of an accident, we shall have demolished the definition; so that, to
use the phrase previously employed,' all the points we have enumerated
might in a certain sense be called 'definitory'. But we must not on
this account expect to find a single line of inquiry which will
apply universally to them all: for this is not an easy thing to
find, and, even were one found, it would be very obscure indeed, and
of little service for the treatise before us. Rather, a special plan
of inquiry must be laid down for each of the classes we have
distinguished, and then, starting from the rules that are
appropriate in each case, it will probably be easier to make our way
right through the task before us. So then, as was said before,' we
must outline a division of our subject, and other questions we must
relegate each to the particular branch to which it most naturally
belongs, speaking of them as 'definitory' and 'generic' questions. The
questions I mean have practically been already assigned to their
several branches.
7
First of all we must define the number of senses borne by the term
'Sameness'. Sameness would be generally regarded as falling, roughly
speaking, into three divisions. We generally apply the term
numerically or specifically or generically-numerically in cases
where there is more than one name but only one thing, e.g. 'doublet'
and 'cloak'; specifically, where there is more than one thing, but
they present no differences in respect of their species, as one man
and another, or one horse and another: for things like this that
fall under the same species are said to be 'specifically the same'.
Similarly, too, those things are called generically the same which
fall under the same genus, such as a horse and a man. It might
appear that the sense in which water from the same spring is called
'the same water' is somehow different and unlike the senses
mentioned above: but really such a case as this ought to be ranked