Aristotle
384-322 B.C.E. - Wrote in Greek
Topics
Written 350 B.C.E
Translated by W. A. Pickard-Cambridge
Topics
By Aristotle
Book I
Part 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.
Part 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.
Part 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.
Part 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.
Part 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.
Part 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 phrase 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.
Part 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 in the same class with the things
that in one way or another are called 'the same' in view of unity of species.
For all such things seem to be of one family and to resemble one another.
For the reaon why all water is said to be specifically the same as all
other water is because of a certain likeness it bears to it, and the only
difference in the case of water drawn from the same spring is this, that
the likeness is more emphatic: that is why we do not distinguish it from
the things that in one way or another are called 'the same' in view of
unity of species. It is generally supposed that the term 'the same' is
most used in a sense agreed on by every one when applied to what is numerically
one. But even so, it is apt to be rendered in more than one sense; its
most literal and primary use is found whenever the sameness is rendered
in reference to an alternative name or definition, as when a cloak is said
to be the same as a doublet, or an animal that walks on two feet is said
to be the same as a man: a second sense is when it is rendered in reference
to a property, as when what can acquire knowledge is called the same as
a man, and what naturally travels upward the same as fire: while a third
use is found when it is rendered in reference to some term drawn from Accident,
as when the creature who is sitting, or who is musical, is called the same
as Socrates. For all these uses mean to signify numerical unity. That what
I have just said is true may be best seen where one form of appellation
is substituted for another. For often when we give the order to call one
of the people who are sitting down, indicating him by name, we change our
description, whenever the person to whom we give the order happens not
to understand us; he will, we think, understand better from some accidental
feature; so we bid him call to us 'the man who is sitting' or 'who is conversing
over there'-clearly supposing ourselves to be indicating the same object
by its name and by its accident.
Part 8
Of 'sameness' then, as has been said,' three senses are to be distinguished.
Now one way to confirm that the elements mentioned above are those out
of which and through which and to which arguments proceed, is by induction:
for if any one were to survey propositions and problems one by one, it
would be seen that each was formed either from the definition of something
or from its property or from its genus or from its accident. Another way
to confirm it is through reasoning. For every predicate of a subject must
of necessity be either convertible with its subject or not: and if it is
convertible, it would be its definition or property, for if it signifies
the essence, it is the definition; if not, it is a property: for this was
what a property is, viz. what is predicated convertibly, but does not signify
the essence. If, on the other hand, it is not predicated convertibly of
the thing, it either is or is not one of the terms contained in the definition
of the subject: and if it be one of those terms, then it will be the genus
or the differentia, inasmuch as the definition consists of genus and differentiae;
whereas, if it be not one of those terms, clearly it would be an accident,
for accident was said' to be what belongs as an attribute to a subject
without being either its definition or its genus or a
property.
Part 9
Next, then, we must distinguish between the classes of predicates
in which the four orders in question are found. These are ten in number:
Essence, Quantity, Quality, Relation, Place, Time, Position, State, Activity,
Passivity. For the accident and genus and property and definition of anything
will always be in one of these categories: for all the propositions found
through these signify either something's essence or its quality or quantity
or some one of the other types of predicate. It is clear, too, on the face
of it that the man who signifies something's essence signifies sometimes
a substance, sometimes a quality, sometimes some one of the other types
of predicate. For when man is set before him and he says that what is set
there is 'a man' or 'an animal', he states its essence and signifies a
substance; but when a white colour is set before him and he says that what
is set there is 'white' or is 'a colour', he states its essence and signifies
a quality. Likewise, also, if a magnitude of a cubit be set before him
and he says that what is set there is a magnitude of a cubit, he will be
describing its essence and signifying a quantity. Likewise, also, in the
other cases: for each of these kinds of predicate, if either it be asserted
of itself, or its genus be asserted of it, signifies an essence: if, on
the other hand, one kind of predicate is asserted of another kind, it does
not signify an essence, but a quantity or a quality or one of the other
kinds of predicate. Such, then, and so many, are the subjects on which
arguments take place, and the materials with which they start. How we are
to acquire them, and by what means we are to become well supplied with
them, falls next to be told.
Part 10
First, then, a definition must be given of a 'dialectical proposition'
and a 'dialectical problem'. For it is not every proposition nor yet every
problem that is to be set down as dialectical: for no one in his senses
would make a proposition of what no one holds, nor yet make a problem of
what is obvious to everybody or to most people: for the latter admits of
no doubt, while to the former no one would assent. Now a dialectical proposition
consists in asking something that is held by all men or by most men or
by the philosophers, i.e. either by all, or by most, or by the most notable
of these, provided it be not contrary to the general opinion; for a man
would probably assent to the view of the philosophers, if it be not contrary
to the opinions of most men. Dialectical propositions also include views
which are like those generally accepted; also propositions which contradict
the contraries of opinions that are taken to be generally accepted, and
also all opinions that are in accordance with the recognized arts. Thus,
supposing it to be a general opinion that the knowledge of contraries is
the same, it might probably pass for a general opinion also that the perception
of contraries is the same: also, supposing it to be a general opinion that
there is but one single science of grammar, it might pass for a general
opinion that there is but one science of flute-playing as well, whereas,
if it be a general opinion that there is more than one science of grammar,
it might pass for a general opinion that there is more than one science
of flute-playing as well: for all these seem to be alike and akin. Likewise,
also, propositions contradicting the contraries of general opinions will
pass as general opinions: for if it be a general opinion that one ought
to do good to one's friends, it will also be a general opinion that one
ought not to do them harm. Here, that one ought to do harm to one's friends
is contrary to the general view, and that one ought not to do them harm
is the contradictory of that contrary. Likewise also, if one ought to do
good to one's friends, one ought not to do good to one's enemies: this
too is the contradictory of the view contrary to the general view; the
contrary being that one ought to do good to one's enemies. Likewise, also,
in other cases. Also, on comparison, it will look like a general opinion
that the contrary predicate belongs to the contrary subject: e.g. if one
ought to do good to one's friends, one ought also to do evil to one's enemies.
it might appear also as if doing good to one's friends were a contrary
to doing evil to one's enemies: but whether this is or is not so in reality
as well will be stated in the course of the discussion upon contraries.
Clearly also, all opinions that are in accordance with the arts are dialectical
propositions; for people are likely to assent to the views held by those
who have made a study of these things, e.g. on a question of medicine they
will agree with the doctor, and on a question of geometry with the geometrician;
and likewise also in other cases.
Part 11
A dialectical problem is a subject of inquiry that contributes
either to choice and avoidance, or to truth and knowledge, and that either
by itself, or as a help to the solution of some other such problem. It
must, moreover, be something on which either people hold no opinion either
way, or the masses hold a contrary opinion to the philosophers, or the
philosophers to the masses, or each of them among themselves. For some
problems it is useful to know with a view to choice or avoidance, e.g.
whether pleasure is to be chosen or not, while some it is useful to know
merely with a view to knowledge, e.g. whether the universe is eternal or
not: others, again, are not useful in and by themselves for either of these
purposes, but yet help us in regard to some such problems; for there are
many things which we do not wish to know in and by themselves, but for
the sake of other things, in order that through them we may come to know
something else. Problems also include questions in regard to which reasonings
conflict (the difficulty then being whether so-and so is so or not, there
being convincing arguments for both views); others also in regard to which
we have no argument because they are so vast, and we find it difficult
to give our reasons, e.g. the question whether the universe is eternal
or no: for into questions of that kind too it is possible to
inquire.
Problems, then, and propositions are to be defined as aforesaid.
A 'thesis' is a supposition of some eminent philosopher that conflicts
with the general opinion; e.g. the view that contradiction is impossible,
as Antisthenes said; or the view of Heraclitus that all things are in motion;
or that Being is one, as Melissus says: for to take notice when any ordinary
person expresses views contrary to men's usual opinions would be silly.
Or it may be a view about which we have a reasoned theory contrary to men's
usual opinions, e.g. the view maintained by the sophists that what is need
not in every case either have come to be or be eternal: for a musician
who is a grammarian 'is' so without ever having 'come to be' so, or being
so eternally. For even if a man does not accept this view, he might do
so on the ground that it is reasonable.
Now a 'thesis' also is a problem, though a problem is not always
a thesis, inasmuch as some problems are such that we have no opinion about
them either way. That a thesis, however, also forms a problem, is clear:
for it follows of necessity from what has been said that either the mass
of men disagree with the philosophers about the thesis, or that the one
or the other class disagree among themselves, seeing that the thesis is
a supposition in conflict with general opinion. Practically all dialectical
problems indeed are now called 'theses'. But it should make no difference
whichever description is used; for our object in thus distinguishing them
has not been to create a terminology, but to recognize what differences
happen to be found between them.
Not every problem, nor every thesis, should be examined, but only
one which might puzzle one of those who need argument, not punishment or
perception. For people who are puzzled to know whether one ought to honour
the gods and love one's parents or not need punishment, while those who
are puzzled to know whether snow is white or not need perception. The subjects
should not border too closely upon the sphere of demonstration, nor yet
be too far removed from it: for the former cases admit of no doubt, while
the latter involve difficulties too great for the art of the
trainer.
Part 12
Having drawn these definitions, we must distinguish how many species
there are of dialectical arguments. There is on the one hand Induction,
on the other Reasoning. Now what reasoning is has been said before: induction
is a passage from individuals to universals, e.g. the argument that supposing
the skilled pilot is the most effective, and likewise the skilled charioteer,
then in general the skilled man is the best at his particular task. Induction
is the more convincing and clear: it is more readily learnt by the use
of the senses, and is applicable generally to the mass of men, though reasoning
is more forcible and effective against contradictious
people.
Part 13
The classes, then, of things about which, and of things out of
which, arguments are constructed, are to be distinguished in the way we
have said before. The means whereby we are to become well supplied with
reasonings are four: (1) the securing of propositions; (2) the power to
distinguish in how many senses particular expression is used; (3) the discovery
of the differences of things; (4) the investigation of likeness. The last
three, as well, are in a certain sense propositions: for it is possible
to make a proposition corresponding to each of them, e.g. (1) 'The desirable
may mean either the honourable or the pleasant or the expedient'; and (2)
Sensation differs from knowledge in that the latter may be recovered again
after it has been lost, while the former cannot'; and (3) The relation
of the healthy to health is like that of the vigorous to vigour'. The first
proposition depends upon the use of one term in several senses, the second
upon the differences of things, the third upon their
likenesses.
Part 14
Propositions should be selected in a number of ways corresponding
to the number of distinctions drawn in regard to the proposition: thus
one may first take in hand the opinions held by all or by most men or by
the philosophers, i.e. by all, or most, or the most notable of them; or
opinions contrary to those that seem to be generally held; and, again,
all opinions that are in accordance with the arts. We must make propositions
also of the contradictories of opinions contrary to those that seem to
be generally held, as was laid down before. It is useful also to make them
by selecting not only those opinions that actually are accepted, but also
those that are like these, e.g. 'The perception of contraries is the same'-the
knowledge of them being so-and 'we see by admission of something into ourselves,
not by an emission'; for so it is, too, in the case of the other senses;
for in hearing we admit something into ourselves; we do not emit; and we
taste in the same way. Likewise also in the other cases. Moreover, all
statements that seem to be true in all or in most cases, should be taken
as a principle or accepted position; for they are posited by those who
do not also see what exception there may be. We should select also from
the written handbooks of argument, and should draw up sketch-lists of them
upon each several kind of subject, putting them down under separate headings,
e.g. 'On Good', or 'On Life'-and that 'On Good' should deal with every
form of good, beginning with the category of essence. In the margin, too,
one should indicate also the opinions of individual thinkers, e.g. 'Empedocles
said that the elements of bodies were four': for any one might assent to
the saying of some generally accepted authority.
Of propositions and problems there are-to comprehend the matter
in outline-three divisions: for some are ethical propositions, some are
on natural philosophy, while some are logical. Propositions such as the
following are ethical, e.g. 'Ought one rather to obey one's parents or
the laws, if they disagree?'; such as this are logical, e.g. 'Is the knowledge
of opposites the same or not?'; while such as this are on natural philosophy,
e.g. 'Is the universe eternal or not?' Likewise also with problems. The
nature of each of the aforesaid kinds of proposition is not easily rendered
in a definition, but we have to try to recognize each of them by means
of the familiarity attained through induction, examining them in the light
of the illustrations given above.
For purposes of philosophy we must treat of these things according
to their truth, but for dialectic only with an eye to general opinion.
All propositions should be taken in their most universal form; then, the
one should be made into many. E.g. 'The knowledge of opposites is the same';
next, 'The knowledge of contraries is the same', and that 'of relative
terms'. In the same way these two should again be divided, as long as division
is possible, e.g. the knowledge of 'good and evil', of 'white and black',
or 'cold and hot'. Likewise also in other cases.
Part 15
On the formation, then, of propositions, the above remarks are
enough. As regards the number of senses a term bears, we must not only
treat of those terms which bear different senses, but we must also try
to render their definitions; e.g. we must not merely say that justice and
courage are called 'good' in one sense, and that what conduces to vigour
and what conduces to health are called so in another, but also that the
former are so called because of a certain intrinsic quality they themselves
have, the latter because they are productive of a certain result and not
because of any intrinsic quality in themselves. Similarly also in other
cases.
Whether a term bears a number of specific meanings or one only,
may be considered by the following means. First, look and see if its contrary
bears a number of meanings, whether the discrepancy between them be one
of kind or one of names. For in some cases a difference is at once displayed
even in the names; e.g. the contrary of 'sharp' in the case of a note is
'flat', while in the case of a solid edge it is 'dull'. Clearly, then,
the contrary of 'sharp' bears several meanings, and if so, also does 'sharp';
for corresponding to each of the former terms the meaning of its contrary
will be different. For 'sharp' will not be the same when contrary to 'dull'
and to 'flat', though 'sharp' is the contrary of each. Again Barhu ('flat',
'heavy') in the case of a note has 'sharp' as its contrary, but in the
case of a solid mass 'light', so that Barhu is used with a number of meanings,
inasmuch as its contrary also is so used. Likewise, also, 'fine' as applied
to a picture has 'ugly' as its contrary, but, as applied to a house, 'ramshackle';
so that 'fine' is an ambiguous term.
In some cases there is no discrepancy of any sort in the names
used, but a difference of kind between the meanings is at once obvious:
e.g. in the case of 'clear' and 'obscure': for sound is called 'clear'
and 'obscure', just as 'colour' is too. As regards the names, then, there
is no discrepancy, but the difference in kind between the meanings is at
once obvious: for colour is not called 'clear' in a like sense to sound.
This is plain also through sensation: for of things that are the same in
kind we have the same sensation, whereas we do not judge clearness by the
same sensation in the case of sound and of colour, but in the latter case
we judge by sight, in the former by hearing. Likewise also with 'sharp'
and 'dull' in regard to flavours and solid edges: here in the latter case
we judge by touch, but in the former by taste. For here again there is
no discrepancy in the names used, in the case either of the original terms
or of their contraries: for the contrary also of sharp in either sense
is 'dull'.
Moreover, see if one sense of a term has a contrary, while another
has absolutely none; e.g. the pleasure of drinking has a contrary in the
pain of thirst, whereas the pleasure of seeing that the diagonal is incommensurate
with the side has none, so that 'pleasure' is used in more than one sense.
To 'love' also, used of the frame of mind, has to 'hate' as its contrary,
while as used of the physical activity (kissing) it has none: clearly,
therefore, to 'love' is an ambiguous term. Further, see in regard to their
intermediates, if some meanings and their contraries have an intermediate,
others have none, or if both have one but not the same one, e.g. 'clear'
and 'obscure' in the case of colours have 'grey' as an intermediate, whereas
in the case of sound they have none, or, if they have, it is 'harsh', as
some people say that a harsh sound is intermediate. 'Clear', then, is an
ambiguous term, and likewise also 'obscure'. See, moreover, if some of
them have more than one intermediate, while others have but one, as is
the case with 'clear' and 'obscure', for in the case of colours there are
numbers of intermediates, whereas in regard to sound there is but one,
viz. 'harsh'.
Again, in the case of the contradictory opposite, look and see
if it bears more than one meaning. For if this bears more than one meaning,
then the opposite of it also will be used in more than one meaning; e.g.
'to fail to see' a phrase with more than one meaning, viz. (1) to fail
to possess the power of sight, (2) to fail to put that power to active
use. But if this has more than one meaning, it follows necessarily that
'to see' also has more than one meaning: for there will be an opposite
to each sense of 'to fail to see'; e.g. the opposite of 'not to possess
the power of sight' is to possess it, while of 'not to put the power of
sight to active use', the opposite is to put it to active
use.
Moreover, examine the case of terms that denote the privation or
presence of a certain state: for if the one term bears more than one meaning,
then so will the remaining term: e.g. if 'to have sense' be used with more
than one meaning, as applied to the soul and to the body, then 'to be wanting
in sense' too will be used with more than one meaning, as applied to the
soul and to the body. That the opposition between the terms now in question
depends upon the privation or presence of a certain state is clear, since
animals naturally possess each kind of 'sense', both as applied to the
soul and as applied to the body.
Moreover, examine the inflected forms. For if 'justly' has more
than one meaning, then 'just', also, will be used with more than one meaning;
for there will be a meaning of 'just' to each of the meanings of 'justly';
e.g. if the word 'justly' be used of judging according to one's own opinion,
and also of judging as one ought, then 'just' also will be used in like
manner. In the same way also, if 'healthy' has more than one meaning, then
'healthily' also will be used with more than one meaning: e.g. if 'healthy'
describes both what produces health and what preserves health and what
betokens health, then 'healthily' also will be used to mean 'in such a
way as to produce' or 'preserve' or 'betoken' health. Likewise also in
other cases, whenever the original term bears more than one meaning, the
inflexion also that is formed from it will be used with more than one meaning,
and vice versa.
Look also at the classes of the predicates signified by the term,
and see if they are the same in all cases. For if they are not the same,
then clearly the term is ambiguous: e.g. 'good' in the case of food means
'productive of pleasure', and in the case of medicine 'productive of health',
whereas as applied to the soul it means to be of a certain quality, e.g.
temperate or courageous or just: and likewise also, as applied to 'man'.
Sometimes it signifies what happens at a certain time, as (e.g.) the good
that happens at the right time: for what happens at the right time is called
good. Often it signifies what is of certain quantity, e.g. as applied to
the proper amount: for the proper amount too is called good. So then the
term 'good' is ambiguous. In the same way also 'clear', as applied to a
body, signifies a colour, but in regard to a note it denotes what is 'easy
to hear'. 'Sharp', too, is in a closely similar case: for the same term
does not bear the same meaning in all its applications: for a sharp note
is a swift note, as the mathematical theorists of harmony tell us, whereas
a sharp (acute) angle is one that is less than a right angle, while a sharp
dagger is one containing a sharp angle (point).
Look also at the genera of the objects denoted by the same term,
and see if they are different without being subaltern, as (e.g.) 'donkey',
which denotes both the animal and the engine. For the definition of them
that corresponds to the name is different: for the one will be declared
to be an animal of a certain kind, and the other to be an engine of a certain
kind. If, however, the genera be subaltern, there is no necessity for the
definitions to be different. Thus (e.g.) 'animal' is the genus of 'raven',
and so is 'bird'. Whenever therefore we say that the raven is a bird, we
also say that it is a certain kind of animal, so that both the genera are
predicated of it. Likewise also whenever we call the raven a 'flying biped
animal', we declare it to be a bird: in this way, then, as well, both the
genera are predicated of raven, and also their definition. But in the case
of genera that are not subaltern this does not happen, for whenever we
call a thing an 'engine', we do not call it an animal, nor vice
versa.
Look also and see not only if the genera of the term before you
are different without being subaltern, but also in the case of its contrary:
for if its contrary bears several senses, clearly the term before you does
so as well.
It is useful also to look at the definition that arises from the
use of the term in combination, e.g. of a 'clear (lit. white) body' of
a 'clear note'. For then if what is peculiar in each case be abstracted,
the same expression ought to remain over. This does not happen in the case
of ambiguous terms, e.g. in the cases just mentioned. For the former will
be body possessing such and such a colour', while the latter will be 'a
note easy to hear'. Abstract, then, 'a body 'and' a note', and the remainder
in each case is not the same. It should, however, have been had the meaning
of 'clear' in each case been synonymous.
Often in the actual definitions as well ambiguity creeps in unawares,
and for this reason the definitions also should be examined. If (e.g.)
any one describes what betokens and what produces health as 'related commensurably
to health', we must not desist but go on to examine in what sense he has
used the term 'commensurably' in each case, e.g. if in the latter case
it means that 'it is of the right amount to produce health', whereas in
the for it means that 'it is such as to betoken what kind of state
prevails'.
Moreover, see if the terms cannot be compared as 'more or less'
or as 'in like manner', as is the case (e.g.) with a 'clear' (lit. white)
sound and a 'clear' garment, and a 'sharp' flavour and a 'sharp' note.
For neither are these things said to be clear or sharp 'in a like degree',
nor yet is the one said to be clearer or sharper than the other. 'Clear',
then, and 'sharp' are ambiguous. For synonyms are always comparable; for
they will always be used either in like manner, or else in a greater degree
in one case.
Now since of genera that are different without being subaltern
the differentiae also are different in kind, e.g. those of 'animal' and
'knowledge' (for the differentiae of these are different), look and see
if the meanings comprised under the same term are differentiae of genera
that are different without being subaltern, as e.g. 'sharp' is of a 'note'
and a 'solid'. For being 'sharp' differentiates note from note, and likewise
also one solid from another. 'Sharp', then, is an ambiguous term: for it
forms differentiae of genera that are different without being
subaltern.
Again, see if the actual meanings included under the same term
themselves have different differentiae, e.g. 'colour' in bodies and 'colour'
in tunes: for the differentiae of 'colour' in bodies are 'sight-piercing'
and 'sight compressing', whereas 'colour' in melodies has not the same
differentiae. Colour, then, is an ambiguous term; for things that are the
same have the same differentiae.
Moreover, since the species is never the differentia of anything,
look and see if one of the meanings included under the same term be a species
and another a differentia, as (e.g.) clear' (lit. white) as applied to
a body is a species of colour, whereas in the case of a note it is a differentia;
for one note is differentiated from another by being
'clear'.
Part 16
The presence, then, of a number of meanings in a term may be investigated
by these and like means. The differences which things present to each other
should be examined within the same genera, e.g. 'Wherein does justice differ
from courage, and wisdom from temperance?'-for all these belong to the
same genus; and also from one genus to another, provided they be not very
much too far apart, e.g. 'Wherein does sensation differ from knowledge?:
for in the case of genera that are very far apart, the differences are
entirely obvious.
Part 17
Likeness should be studied, first, in the case of things belonging
to different genera, the formulae being 'A:B = C:D' (e.g. as knowledge
stands to the object of knowledge, so is sensation related to the object
of sensation), and 'As A is in B, so is C in D' (e.g. as sight is in the
eye, so is reason in the soul, and as is a calm in the sea, so is windlessness
in the air). Practice is more especially needed in regard to terms that
are far apart; for in the case of the rest, we shall be more easily able
to see in one glance the points of likeness. We should also look at things
which belong to the same genus, to see if any identical attribute belongs
to them all, e.g. to a man and a horse and a dog; for in so far as they
have any identical attribute, in so far they are alike.
Part 18
It is useful to have examined the number of meanings of a term
both for clearness' sake (for a man is more likely to know what it is he
asserts, if it bas been made clear to him how many meanings it may have),
and also with a view to ensuring that our reasonings shall be in accordance
with the actual facts and not addressed merely to the term used. For as
long as it is not clear in how many senses a term is used, it is possible
that the answerer and the questioner are not directing their minds upon
the same thing: whereas when once it has been made clear how many meanings
there are, and also upon which of them the former directs his mind when
he makes his assertion, the questioner would then look ridiculous if he
failed to address his argument to this. It helps us also both to avoid
being misled and to mislead by false reasoning: for if we know the number
of meanings of a term, we shall certainly never be misled by false reasoning,
but shall know if the questioner fails to address his argument to the same
point; and when we ourselves put the questions we shall be able to mislead
him, if our answerer happens not to know the number of meanings of our
terms. This, however, is not possible in all cases, but only when of the
many senses some are true and others are false. This manner of argument,
however, does not belong properly to dialectic; dialecticians should therefore
by all means beware of this kind of verbal discussion, unless any one is
absolutely unable to discuss the subject before him in any other
way.
The discovery of the differences of things helps us both in reasonings
about sameness and difference, and also in recognizing what any particular
thing is. That it helps us in reasoning about sameness and difference is
clear: for when we have discovered a difference of any kind whatever between
the objects before us, we shall already have shown that they are not the
same: while it helps us in recognizing what a thing is, because we usually
distinguish the expression that is proper to the essence of each particular
thing by means of the differentiae that are proper to
it.
The examination of likeness is useful with a view both to inductive
arguments and to hypothetical reasonings, and also with a view to the rendering
of definitions. It is useful for inductive arguments, because it is by
means of an induction of individuals in cases that are alike that we claim
to bring the universal in evidence: for it is not easy to do this if we
do not know the points of likeness. It is useful for hypothetical reasonings
because it is a general opinion that among similars what is true of one
is true also of the rest. If, then, with regard to any of them we are well
supplied with matter for a discussion, we shall secure a preliminary admission
that however it is in these cases, so it is also in the case before us:
then when we have shown the former we shall have shown, on the strength
of the hypothesis, the matter before us as well: for we have first made
the hypothesis that however it is in these cases, so it is also in the
case before us, and have then proved the point as regards these cases.
It is useful for the rendering of definitions because, if we are able to
see in one glance what is the same in each individual case of it, we shall
be at no loss into what genus we ought to put the object before us when
we define it: for of the common predicates that which is most definitely
in the category of essence is likely to be the genus. Likewise, also, in
the case of objects widely divergent, the examination of likeness is useful
for purposes of definition, e.g. the sameness of a calm at sea, and windlessness
in the air (each being a form of rest), and of a point on a line and the
unit in number-each being a starting point. If, then, we render as the
genus what is common to all the cases, we shall get the credit of defining
not inappropriately. Definition-mongers too nearly always render them in
this way: they declare the unit to be the startingpoint of number, and
the point the startingpoint of a line. It is clear, then, that they place
them in that which is common to both as their genus.
The means, then, whereby reasonings are effected, are these: the
commonplace rules, for the observance of which the aforesaid means are
useful, are as follows.
Topics
By Aristotle
Book II
Part 1
Of problems some are universal, others particular. Universal problems are
such as 'Every pleasure is good' and 'No pleasure is good'; particular
problems are such as 'Some pleasure is good' and 'Some pleasure is not
good'. The methods of establishing and overthrowing a view universally
are common to both kinds of problems; for when we have shown that a predicate
belongs in every case, we shall also have shown that it belongs in some
cases. Likewise, also, if we show that it does not belong in any case,
we shall also have shown that it does not belong in every case. First,
then, we must speak of the methods of overthrowing a view universally,
because such are common to both universal and particular problems, and
because people more usually introduce theses asserting a predicate than
denying it, while those who argue with them overthrow it. The conversion
of an appropriate name which is drawn from the element 'accident' is an
extremely precarious thing; for in the case of accidents and in no other
it is possible for something to be true conditionally and not universally.
Names drawn from the elements 'definition' and 'property' and 'genus' are
bound to be convertible; e.g. if 'to be an animal that walks on two feet
is an attribute of S', then it will be true by conversion to say that 'S
is an animal that walks on two feet'. Likewise, also, if drawn from the
genus; for if 'to be an animal is an attribute of S', then 'S is an animal'.
The same is true also in the case of a property; for if 'to be capable
of learning grammar is an attribute of S', then 'S will be capable of learning
grammar'. For none of these attributes can possibly belong or not belong
in part; they must either belong or not belong absolutely. In the case
of accidents, on the other hand, there is nothing to prevent an attribute
(e.g. whiteness or justice) belonging in part, so that it is not enough
to show that whiteness or justice is an attribute of a man in order to
show that he is white or just; for it is open to dispute it and say that
he is white or just in part only. Conversion, then, is not a necessary
process in the case of accidents.
We must also define the errors that occur in problems. They are
of two kinds, caused either by false statement or by transgression of the
established diction. For those who make false statements, and say that
an attribute belongs to thing which does not belong to it, commit error;
and those who call objects by the names of other objects (e.g. calling
a planetree a 'man') transgress the established terminology.
Part 2
Now one commonplace rule is to look and see if a man has ascribed
as an accident what belongs in some other way. This mistake is most commonly
made in regard to the genera of things, e.g. if one were to say that white
happens (accidit) to be a colour-for being a colour does not happen by
accident to white, but colour is its genus. The assertor may of course
define it so in so many words, saying (e.g.) that 'Justice happens (accidit)
to be a virtue'; but often even without such definition it is obvious that
he has rendered the genus as an accident; e.g. suppose that one were to
say that whiteness is coloured or that walking is in motion. For a predicate
drawn from the genus is never ascribed to the species in an inflected form,
but always the genera are predicated of their species literally; for the
species take on both the name and the definition of their genera. A man
therefore who says that white is 'coloured' has not rendered 'coloured'
as its genus, seeing that he has used an inflected form, nor yet as its
property or as its definition: for the definition and property of a thing
belong to it and to nothing else, whereas many things besides white are
coloured, e.g. a log, a stone, a man, and a horse. Clearly then he renders
it as an accident.
Another rule is to examine all cases where a predicate has been
either asserted or denied universally to belong to something. Look at them
species by species, and not in their infinite multitude: for then the inquiry
will proceed more directly and in fewer steps. You should look and begin
with the most primary groups, and then proceed in order down to those that
are not further divisible: e.g. if a man has said that the knowledge of
opposites is the same, you should look and see whether it be so of relative
opposites and of contraries and of terms signifying the privation or presence
of certain states, and of contradictory terms. Then, if no clear result
be reached so far in these cases, you should again divide these until you
come to those that are not further divisible, and see (e.g.) whether it
be so of just deeds and unjust, or of the double and the half, or of blindness
and sight, or of being and not-being: for if in any case it be shown that
the knowledge of them is not the same we shall have demolished the problem.
Likewise, also, if the predicate belongs in no case. This rule is convertible
for both destructive and constructive purposes: for if, when we have suggested
a division, the predicate appears to hold in all or in a large number of
cases, we may then claim that the other should actually assert it universally,
or else bring a negative instance to show in what case it is not so: for
if he does neither of these things, a refusal to assert it will make him
look absurd.
Another rule is to make definitions both of an accident and of
its subject, either of both separately or else of one of them, and then
look and see if anything untrue has been assumed as true in the definitions.
Thus (e.g.) to see if it is possible to wrong a god, ask what is 'to wrong'?
For if it be 'to injure deliberately', clearly it is not possible for a
god to be wronged: for it is impossible that God should be injured. Again,
to see if the good man is jealous, ask who is the 'jealous' man and what
is 'jealousy'. For if 'jealousy' is pain at the apparent success of some
well-behaved person, clearly the good man is not jealous: for then he would
be bad. Again, to see if the indignant man is jealous, ask who each of
them is: for then it will be obvious whether the statement is true or false;
e.g. if he is 'jealous' who grieves at the successes of the good, and he
is 'indignant' who grieves at the successes of the evil, then clearly the
indignant man would not be jealous. A man should substitute definitions
also for the terms contained in his definitions, and not stop until he
comes to a familiar term: for often if the definition be rendered whole,
the point at issue is not cleared up, whereas if for one of the terms used
in the definition a definition be stated, it becomes
obvious.
Moreover, a man should make the problem into a proposition for
himself, and then bring a negative instance against it: for the negative
instance will be a ground of attack upon the assertion. This rule is very
nearly the same as the rule to look into cases where a predicate has been
attributed or denied universally: but it differs in the turn of the
argument.
Moreover, you should define what kind of things should be called
as most men call them, and what should not. For this is useful both for
establishing and for overthrowing a view: e.g. you should say that we ought
to use our terms to mean the same things as most people mean by them, but
when we ask what kind of things are or are not of such and such a kind,
we should not here go with the multitude: e.g. it is right to call 'healthy'
whatever tends to produce health, as do most men: but in saying whether
the object before us tends to produce health or not, we should adopt the
language no longer of the multitude but of the doctor.
Part 3
Moreover, if a term be used in several senses, and it has been
laid down that it is or that it is not an attribute of S, you should show
your case of one of its several senses, if you cannot show it of both.
This rule is to be observed in cases where the difference of meaning is
undetected; for supposing this to be obvious, then the other man will object
that the point which he himself questioned has not been discussed, but
only the other point. This commonplace rule is convertible for purposes
both of establishing and of overthrowing a view. For if we want to establish
a statement, we shall show that in one sense the attribute belongs, if
we cannot show it of both senses: whereas if we are overthrowing a statement,
we shall show that in one sense the attribute does not belong, if we cannot
show it of both senses. Of course, in overthrowing a statement there is
no need to start the discussion by securing any admission, either when
the statement asserts or when it denies the attribute universally: for
if we show that in any case whatever the attribute does not belong, we
shall have demolished the universal assertion of it, and likewise also
if we show that it belongs in a single case, we shall demolish the universal
denial of it. Whereas in establishing a statement we ought to secure a
preliminary admission that if it belongs in any case whatever, it belongs
universally, supposing this claim to be a plausible one. For it is not
enough to discuss a single instance in order to show that an attribute
belongs universally; e.g. to argue that if the soul of man be immortal,
then every soul is immortal, so that a previous admission must be secured
that if any soul whatever be immortal, then every soul is immortal. This
is not to be done in every case, but only whenever we are not easily able
to quote any single argument applying to all cases in common, as (e.g.)
the geometrician can argue that the triangle has its angles equal to two
right angles.
If, again, the variety of meanings of a term be obvious, distinguish
how many meanings it has before proceeding either to demolish or to establish
it: e.g. supposing 'the right' to mean 'the expedient' or 'the honourable',
you should try either to establish or to demolish both descriptions of
the subject in question; e.g. by showing that it is honourable and expedient,
or that it is neither honourable nor expedient. Supposing, however, that
it is impossible to show both, you should show the one, adding an indication
that it is true in the one sense and not in the other. The same rule applies
also when the number of senses into which it is divided is more than
two.
Again, consider those expressions whose meanings are many, but
differ not by way of ambiguity of a term, but in some other way: e.g. 'The
science of many things is one': here 'many things' may mean the end and
the means to that end, as (e.g.) medicine is the science both of producing
health and of dieting; or they may be both of them ends, as the science
of contraries is said to be the same (for of contraries the one is no more
an end than the other); or again they may be an essential and an accidental
attribute, as (e.g.) the essential fact that the triangle has its angles
equal to two right angles, and the accidental fact that the equilateral
figure has them so: for it is because of the accident of the equilateral
triangle happening to be a triangle that we know that it has its angles
equal to two right angles. If, then, it is not possible in any sense of
the term that the science of many things should be the same, it clearly
is altogether impossible that it should be so; or, if it is possible in
some sense, then clearly it is possible. Distinguish as many meanings as
are required: e.g. if we want to establish a view, we should bring forward
all such meanings as admit that view and should divide them only into those
meanings which also are required for the establishment of our case: whereas
if we want to overthrow a view, we should bring forward all that do not
admit that view, and leave the rest aside. We must deal also in these cases
as well with any uncertainty about the number of meanings involved. Further,
that one thing is, or is not, 'of' another should be established by means
of the same commonplace rules; e.g. that a particular science is of a particular
thing, treated either as an end or as a means to its end, or as accidentally
connected with it; or again that it is not 'of' it in any of the aforesaid
ways. The same rule holds true also of desire and all other terms that
have more than one object. For the 'desire of X' may mean the desire of
it as an end (e.g. the desire of health) or as a means to an end (e.g.
the desire of being doctored), or as a thing desired accidentally, as,
in the case of wine, the sweet-toothed person desires it not because it
is wine but because it is sweet. For essentially he desires the sweet,
and only accidentally the wine: for if it be dry, he no longer desires
it. His desire for it is therefore accidental. This rule is useful in dealing
with relative terms: for cases of this kind are generally cases of relative
terms.
Part 4
Moreover, it is well to alter a term into one more familiar, e.g.
to substitute 'clear' for 'exact' in describing a conception, and 'being
fussy' for 'being busy': for when the expression is made more familiar,
the thesis becomes easier to attack. This commonplace rule also is available
for both purposes alike, both for establishing and for overthrowing a
view.
In order to show that contrary attributes belong to the same thing,
look at its genus; e.g. if we want to show that rightness and wrongness
are possible in regard to perception, and to perceive is to judge, while
it is possible to judge rightly or wrongly, then in regard to perception
as well rightness and wrongness must be possible. In the present instance
the proof proceeds from the genus and relates to the species: for 'to judge'
is the genus of 'to -perceive'; for the man who perceives judges in a certain
way. But per contra it may proceed from the species to the genus: for all
the attributes that belong to the species belong to the genus as well;
e.g. if there is a bad and a good knowledge there is also a bad and a good
disposition: for 'disposition' is the genus of knowledge. Now the former
commonplace argument is fallacious for purposes of establishing a view,
while the second is true. For there is no necessity that all the attributes
that belong to the genus should belong also to the species; for 'animal'
is flying and quadruped, but not so 'man'. All the attributes, on the other
hand, that belong to the species must of necessity belong also to the genus;
for if 'man' is good, then animal also is good. On the other hand, for
purposes of overthrowing a view, the former argument is true while the
latter is fallacious; for all the attributes which do not belong to the
genus do not belong to the species either; whereas all those that are wanting
to the species are not of necessity wanting to the genus.
Since those things of which the genus is predicated must also of
necessity have one of its species predicated of them, and since those things
that are possessed of the genus in question, or are described by terms
derived from that genus, must also of necessity be possessed of one of
its species or be described by terms derived from one of its species (e.g.
if to anything the term 'scientific knowledge' be applied, then also there
will be applied to it the term 'grammatical' or 'musical' knowledge, or
knowledge of one of the other sciences; and if any one possesses scientific
knowledge or is described by a term derived from 'science', then he will
also possess grammatical or musical knowledge or knowledge of one of the
other sciences, or will be described by a term derived from one of them,
e.g. as a 'grammarian' or a 'musician')-therefore if any expression be
asserted that is in any way derived from the genus (e.g. that the soul
is in motion), look and see whether it be possible for the soul to be moved
with any of the species of motion; whether (e.g.) it can grow or be destroyed
or come to be, and so forth with all the other species of motion. For if
it be not moved in any of these ways, clearly it does not move at all.
This commonplace rule is common for both purposes, both for overthrowing
and for establishing a view: for if the soul moves with one of the species
of motion, clearly it does move; while if it does not move with any of
the species of motion, clearly it does not move.
If you are not well equipped with an argument against the assertion,
look among the definitions, real or apparent, of the thing before you,
and if one is not enough, draw upon several. For it will be easier to attack
people when committed to a definition: for an attack is always more easily
made on definitions.
Moreover, look and see in regard to the thing in question, what
it is whose reality conditions the reality of the thing in question, or
what it is whose reality necessarily follows if the thing in question be
real: if you wish to establish a view inquire what there is on whose reality
the reality of the thing in question will follow (for if the former be
shown to be real, then the thing in question will also have been shown
to be real); while if you want to overthrow a view, ask what it is that
is real if the thing in question be real, for if we show that what follows
from the thing in question is unreal, we shall have demolished the thing
in question.
Moreover, look at the time involved, to see if there be any discrepancy
anywhere: e.g. suppose a man to have stated that what is being nourished
of necessity grows: for animals are always of necessity being nourished,
but they do not always grow. Likewise, also, if he has said that knowing
is remembering: for the one is concerned with past time, whereas the other
has to do also with the present and the future. For we are said to know
things present and future (e.g. that there will be an eclipse), whereas
it is impossible to remember anything save what is in the
past.
Part 5
Moreover, there is the sophistic turn of argument, whereby we draw
our opponent into the kind of statement against which we shall be well
supplied with lines of argument. This process is sometimes a real necessity,
sometimes an apparent necessity, sometimes neither an apparent nor a real
necessity. It is really necessary whenever the answerer has denied any
view that would be useful in attacking the thesis, and the questioner thereupon
addresses his arguments to the support of this view, and when moreover
the view in question happens to be one of a kind on which he has a good
stock of lines of argument. Likewise, also, it is really necessary whenever
he (the questioner) first, by an induction made by means of the view laid
down, arrives at a certain statement and then tries to demolish that statement:
for when once this has been demolished, the view originally laid down is
demolished as well. It is an apparent necessity, when the point to which
the discussion comes to be directed appears to be useful, and relevant
to the thesis, without being really so; whether it be that the man who
is standing up to the argument has refused to concede something, or whether
he (the questioner) has first reached it by a plausible induction based
upon the thesis and then tries to demolish it. The remaining case is when
the point to which the discussion comes to be directed is neither really
nor apparently necessary, and it is the answerer's luck to be confuted
on a mere side issue You should beware of the last of the aforesaid methods;
for it appears to be wholly disconnected from, and foreign to, the art
of dialectic. For this reason, moreover, the answerer should not lose his
temper, but assent to those statements that are of no use in attacking
the thesis, adding an indication whenever he assents although he does not
agree with the view. For, as a rule, it increases the confusion of questioners
if, after all propositions of this kind have been granted them, they can
then draw no conclusion.
Moreover, any one who has made any statement whatever has in a
certain sense made several statements, inasmuch as each statement has a
number of necessary consequences: e.g. the man who said 'X is a man' has
also said that it is an animal and that it is animate and a biped and capable
of acquiring reason and knowledge, so that by the demolition of any single
one of these consequences, of whatever kind, the original statement is
demolished as well. But you should beware here too of making a change to
a more difficult subject: for sometimes the consequence, and sometimes
the original thesis, is the easier to demolish.
Part 6
In regard to subjects which must have one and one only of two predicates,
as (e.g.) a man must have either a disease or health, supposing we are
well supplied as regards the one for arguing its presence or absence, we
shall be well equipped as regards the remaining one as well. This rule
is convertible for both purposes: for when we have shown that the one attribute
belongs, we shall have shown that the remaining one does not belong; while
if we show that the one does not belong, we shall have shown that the remaining
one does belong. Clearly then the rule is useful for both
purposes.
Moreover, you may devise a line of attack by reinterpreting a term
in its literal meaning, with the implication that it is most fitting so
to take it rather than in its established meaning: e.g. the expression
'strong at heart' will suggest not the courageous man, according to the
use now established, but the man the state of whose heart is strong; just
as also the expression 'of a good hope' may be taken to mean the man who
hopes for good things. Likewise also 'well-starred' may be taken to mean
the man whose star is good, as Xenocrates says 'well-starred is he who
has a noble soul'.' For a man's star is his soul.
Some things occur of necessity, others usually, others however
it may chance; if therefore a necessary event has been asserted to occur
usually, or if a usual event (or, failing such an event itself, its contrary)
has been stated to occur of necessity, it always gives an opportunity for
attack. For if a necessary event has been asserted to occur usually, clearly
the speaker has denied an attribute to be universal which is universal,
and so has made a mistake: and so he has if he has declared the usual attribute
to be necessary: for then he declares it to belong universally when it
does not so belong. Likewise also if he has declared the contrary of what
is usual to be necessary. For the contrary of a usual attribute is always
a comparatively rare attribute: e.g. if men are usually bad, they are comparatively
seldom good, so that his mistake is even worse if he has declared them
to be good of necessity. The same is true also if he has declared a mere
matter of chance to happen of necessity or usually; for a chance event
happens neither of necessity nor usually. If the thing happens usually,
then even supposing his statement does not distinguish whether he meant
that it happens usually or that it happens necessarily, it is open to you
to discuss it on the assumption that he meant that it happens necessarily:
e.g. if he has stated without any distinction that disinherited persons
are bad, you may assume in discussing it that he means that they are so
necessarily.
Moreover, look and see also if he has stated a thing to be an accident
of itself, taking it to be a different thing because it has a different
name, as Prodicus used to divide pleasures into joy and delight and good
cheer: for all these are names of the same thing, to wit, Pleasure. If
then any one says that joyfulness is an accidental attribute of cheerfulness,
he would be declaring it to be an accidental attribute of
itself.
Part 7
Inasmuch as contraries can be conjoined with each other in six
ways, and four of these conjunctions constitute a contrariety, we must
grasp the subject of contraries, in order that it may help us both in demolishing
and in establishing a view. Well then, that the modes of conjunction are
six is clear: for either (1) each of the contrary verbs will be conjoined
to each of the contrary objects; and this gives two modes: e.g. to do good
to friends and to do evil to enemies, or per contra to do evil to friends
and to do good to enemies. Or else (2) both verbs may be attached to one
object; and this too gives two modes, e.g. to do good to friends and to
do evil to friends, or to do good to enemies and to do evil to enemies.
Or (3) a single verb may be attached to both objects: and this also gives
two modes; e.g. to do good to friends and to do good to enemies, or to
do evil to friends and evil to enemies.
The first two then of the aforesaid conjunctions do not constitute
any contrariety; for the doing of good to friends is not contrary to the
doing of evil to enemies: for both courses are desirable and belong to
the same disposition. Nor is the doing of evil to friends contrary to the
doing of good to enemies: for both of these are objectionable and belong
to the same disposition: and one objectionable thing is not generally thought
to be the contrary of another, unless the one be an expression denoting
an excess, and the other an expression denoting a defect: for an excess
is generally thought to belong to the class of objectionable things, and
likewise also a defect. But the other four all constitute a contrariety.
For to do good to friends is contrary to the doing of evil to friends:
for it proceeds from the contrary disposition, and the one is desirable,
and the other objectionable. The case is the same also in regard to the
other conjunctions: for in each combination the one course is desirable,
and the other objectionable, and the one belongs to a reasonable disposition
and the other to a bad. Clearly, then, from what has been said, the same
course has more than one contrary. For the doing of good to friends has
as its contrary both the doing of good to enemies and the doing of evil
to friends. Likewise, if we examine them in the same way, we shall find
that the contraries of each of the others also are two in number. Select
therefore whichever of the two contraries is useful in attacking the
thesis.
Moreover, if the accident of a thing have a contrary, see whether
it belongs to the subject to which the accident in question has been declared
to belong: for if the latter belongs the former could not belong; for it
is impossible that contrary predicates should belong at the same time to
the same thing.
Or again, look and see if anything has been said about something,
of such a kind that if it be true, contrary predicates must necessarily
belong to the thing: e.g. if he has said that the 'Ideas' exist in us.
For then the result will be that they are both in motion and at rest, and
moreover that they are objects both of sensation and of thought. For according
to the views of those who posit the existence of Ideas, those Ideas are
at rest and are objects of thought; while if they exist in us, it is impossible
that they should be unmoved: for when we move, it follows necessarily that
all that is in us moves with us as well. Clearly also they are objects
of sensation, if they exist in us: for it is through the sensation of sight
that we recognize the Form present in each individual.
Again, if there be posited an accident which has a contrary, look
and see if that which admits of the accident will admit of its contrary
as well: for the same thing admits of contraries. Thus (e.g.) if he has
asserted that hatred follows anger, hatred would in that case be in the
'spirited faculty': for that is where anger is. You should therefore look
and see if its contrary, to wit, friendship, be also in the 'spirited faculty':
for if not-if friendship is in the faculty of desire-then hatred could
not follow anger. Likewise also if he has asserted that the faculty of
desire is ignorant. For if it were capable of ignorance, it would be capable
of knowledge as well: and this is not generally held-I mean that the faculty
of desire is capable of knowledge. For purposes, then, of overthrowing
a view, as has been said, this rule should be observed: but for purposes
of establishing one, though the rule will not help you to assert that the
accident actually belongs, it will help you to assert that it may possibly
belong. For having shown that the thing in question will not admit of the
contrary of the accident asserted, we shall have shown that the accident
neither belongs nor can possibly belong; while on the other hand, if we
show that the contrary belongs, or that the thing is capable of the contrary,
we shall not indeed as yet have shown that the accident asserted does belong
as well; our proof will merely have gone to this point, that it is possible
for it to belong.
Part 8
Seeing that the modes of opposition are four in number, you should
look for arguments among the contradictories of your terms, converting
the order of their sequence, both when demolishing and when establishing
a view, and you should secure them by means of induction-such arguments
(e.g.) as that man be an animal, what is not an animal is not a man': and
likewise also in other instances of contradictories. For in those cases
the sequence is converse: for 'animal' follows upon 'man but 'not-animal'
does not follow upon 'not-man', but conversely 'not-man' upon 'not-animal'.
In all cases, therefore, a postulate of this sort should be made, (e.g.)
that 'If the honourable is pleasant, what is not pleasant is not honourable,
while if the latter be untrue, so is the former'. Likewise, also, 'If what
is not pleasant be not honourable, then what is honourable is pleasant'.
Clearly, then, the conversion of the sequence formed by contradiction of
the terms of the thesis is a method convertible for both
purposes.
Then look also at the case of the contraries of S and P in the
thesis, and see if the contrary of the one follows upon the contrary of
the other, either directly or conversely, both when you are demolishing
and when you are establishing a view: secure arguments of this kind as
well by means of induction, so far as may be required. Now the sequence
is direct in a case such as that of courage and cowardice: for upon the
one of them virtue follows, and vice upon the other; and upon the one it
follows that it is desirable, while upon the other it follows that it is
objectionable. The sequence, therefore, in the latter case also is direct;
for the desirable is the contrary of the objectionable. Likewise also in
other cases. The sequence is, on the other hand, converse in such a case
as this: Health follows upon vigour, but disease does not follow upon debility;
rather debility follows upon disease. In this case, then, clearly the sequence
is converse. Converse sequence is, however, rare in the case of contraries;
usually the sequence is direct. If, therefore, the contrary of the one
term does not follow upon the contrary of the other either directly or
conversely, clearly neither does the one term follow upon the other in
the statement made: whereas if the one followed the other in the case of
the contraries, it must of necessity do so as well in the original
statement.
You should look also into cases of the privation or presence of
a state in like manner to the case of contraries. Only, in the case of
such privations the converse sequence does not occur: the sequence is always
bound to be direct: e.g. as sensation follows sight, while absence of sensation
follows blindness. For the opposition of sensation to absence of sensation
is an opposition of the presence to the privation of a state: for the one
of them is a state, and the other the privation of it.
The case of relative terms should also be studied in like manner
to that of a state and its privation: for the sequence of these as well
is direct; e.g. if 3/1 is a multiple, then 1/3 is a fraction: for 3/1 is
relative to 1/3, and so is a multiple to a fraction. Again, if knowledge
be a conceiving, then also the object of knowledge is an object of conception;
and if sight be a sensation, then also the object of sight is an object
of sensation. An objection may be made that there is no necessity for the
sequence to take place, in the case of relative terms, in the way described:
for the object of sensation is an object of knowledge, whereas sensation
is not knowledge. The objection is, however, not generally received as
really true; for many people deny that there is knowledge of objects of
sensation. Moreover, the principle stated is just as useful for the contrary
purpose, e.g. to show that the object of sensation is not an object of
knowledge, on the ground that neither is sensation knowledge.
Part 9
Again look at the case of the co-ordinates and inflected forms
of the terms in the thesis, both in demolishing and in establishing it.
By co-ordinates' are meant terms such as the following: 'Just deeds' and
the 'just man' are coordinates of 'justice', and 'courageous deeds' and
the 'courageous man' are co-ordinates of courage. Likewise also things
that tend to produce and to preserve anything are called co-ordinates of
that which they tend to produce and to preserve, as e.g. 'healthy habits'
are co-ordinates of 'health' and a 'vigorous constitutional' of a 'vigorous
constitution' and so forth also in other cases. 'Co-ordinate', then, usually
describes cases such as these, whereas 'inflected forms' are such as the
following: 'justly', 'courageously', 'healthily', and such as are formed
in this way. It is usually held that words when used in their inflected
forms as well are co-ordinates, as (e.g.) 'justly' in relation to justice,
and 'courageously' to courage; and then 'co-ordinate' describes all the
members of the same kindred series, e.g. 'justice', 'just', of a man or
an act, 'justly'. Clearly, then, when any one member, whatever its kind,
of the same kindred series is shown to be good or praiseworthy, then all
the rest as well come to be shown to be so: e.g. if 'justice' be something
praiseworthy, then so will 'just', of a man or thing, and 'justly' connote
something praiseworthy. Then 'justly' will be rendered also 'praiseworthily',
derived will by the same inflexion from 'the praiseworthy' whereby 'justly'
is derived from 'justice'.
Look not only in the case of the subject mentioned, but also in
the case of its contrary, for the contrary predicate: e.g. argue that good
is not necessarily pleasant; for neither is evil painful: or that, if the
latter be the case, so is the former. Also, if justice be knowledge, then
injustice is ignorance: and if 'justly' means 'knowingly' and 'skilfully',
then 'unjustly' means 'ignorantly' and 'unskilfully': whereas if the latter
be not true, neither is the former, as in the instance given just now:
for 'unjustly' is more likely to seem equivalent to 'skilfully' than to
'unskilfully'. This commonplace rule has been stated before in dealing
with the sequence of contraries; for all we are claiming now is that the
contrary of P shall follow the contrary of S.
Moreover, look at the modes of generation and destruction of a
thing, and at the things which tend to produce or to destroy it, both in
demolishing and in establishing a view. For those things whose modes of
generation rank among good things, are themselves also good; and if they
themselves be good, so also are their modes of generation. If, on the other
hand, their modes of generation be evil, then they themselves also are
evil. In regard to modes of destruction the converse is true: for if the
modes of destruction rank as good things, then they themselves rank as
evil things; whereas if the modes of destruction count as evil, they themselves
count as good. The same argument applies also to things tending to produce
and destroy: for things whose productive causes are good, themselves also
rank as good; whereas if causes destructive of them are good, they themselves
rank as evil.
Part 10
Again, look at things which are like the subject in question, and
see if they are in like case; e.g. if one branch of knowledge has more
than one object, so also will one opinion; and if to possess sight be to
see, then also to possess hearing will be to hear. Likewise also in the
case of other things, both those which are and those which are generally
held to be like. The rule in question is useful for both purposes; for
if it be as stated in the case of some one like thing, it is so with the
other like things as well, whereas if it be not so in the case of some
one of them, neither is it so in the case of the others. Look and see also
whether the cases are alike as regards a single thing and a number of things:
for sometimes there is a discrepancy. Thus, if to 'know' a thing be to
'think of' it, then also to 'know many things' is to 'be thinking of many
things'; whereas this is not true; for it is possible to know many things
but not to be thinking of them. If, then, the latter proposition be not
true, neither was the former that dealt with a single thing, viz. that
to 'know' a thing is to 'think of' it.
Moreover, argue from greater and less degrees. In regard to greater
degrees there are four commonplace rules. One is: See whether a greater
degree of the predicate follows a greater degree of the subject: e.g. if
pleasure be good, see whether also a greater pleasure be a greater good:
and if to do a wrong be evil, see whether also to do a greater wrong is
a greater evil. Now this rule is of use for both purposes: for if an increase
of the accident follows an increase of the subject, as we have said, clearly
the accident belongs; while if it does not follow, the accident does not
belong. You should establish this by induction. Another rule is: If one
predicate be attributed to two subjects; then supposing it does not belong
to the subject to which it is the more likely to belong, neither does it
belong where it is less likely to belong; while if it does belong where
it is less likely to belong, then it belongs as well where it is more likely.
Again: If two predicates be attributed to one subject, then if the one
which is more generally thought to belong does not belong, neither does
the one that is less generally thought to belong; or, if the one that is
less generally thought to belong does belong, so also does the other. Moreover:
If two predicates be attributed to two subjects, then if the one which
is more usually thought to belong to the one subject does not belong, neither
does the remaining predicate belong to the remaining subject; or, if the
one which is less usually thought to belong to the one subject does belong,
so too does the remaining predicate to the remaining
subject.
Moreover, you can argue from the fact that an attribute belongs,
or is generally supposed to belong, in a like degree, in three ways, viz.
those described in the last three rules given in regard to a greater degree.'
For supposing that one predicate belongs, or is supposed to belong, to
two subjects in a like degree, then if it does not belong to the one, neither
does it belong to the other; while if it belongs to the one, it belongs
to the remaining one as well. Or, supposing two predicates to belong in
a like degree to the same subject, then, if the one does not belong, neither
does the remaining one; while if the one does belong, the remaining one
belongs as well. The case is the same also if two predicates belong in
a like degree to two subjects; for if the one predicate does not belong
to the one subject, neither does the remaining predicate belong to the
remaining subject, while if the one predicate does belong to the one subject,
the remaining predicate belongs to the remaining subject as
well.
Part 11
You can argue, then, from greater or less or like degrees of truth
in the aforesaid number of ways. Moreover, you should argue from the addition
of one thing to another. If the addition of one thing to another makes
that other good or white, whereas formerly it was not white or good, then
the thing added will be white or good-it will possess the character it
imparts to the whole as well. Moreover, if an addition of something to
a given object intensifies the character which it had as given, then the
thing added will itself as well be of that character. Likewise, also, in
the case of other attributes. The rule is not applicable in all cases,
but only in those in which the excess described as an 'increased intensity'
is found to take place. The above rule is, however, not convertible for
overthrowing a view. For if the thing added does not make the other good,
it is not thereby made clear whether in itself it may not be good: for
the addition of good to evil does not necessarily make the whole good,
any more than the addition of white to black makes the whole
white.
Again, any predicate of which we can speak of greater or less degrees
belongs also absolutely: for greater or less degrees of good or of white
will not be attributed to what is not good or white: for a bad thing will
never be said to have a greater or less degree of goodness than another,
but always of badness. This rule is not convertible, either, for the purpose
of overthrowing a predication: for several predicates of which we cannot
speak of a greater degree belong absolutely: for the term 'man' is not
attributed in greater and less degrees, but a man is a man for all
that.
You should examine in the same way predicates attributed in a given
respect, and at a given time and place: for if the predicate be possible
in some respect, it is possible also absolutely. Likewise, also, is what
is predicated at a given time or place: for what is absolutely impossible
is not possible either in any respect or at any place or time. An objection
may be raised that in a given respect people may be good by nature, e.g.
they may be generous or temperately inclined, while absolutely they are
not good by nature, because no one is prudent by nature. Likewise, also,
it is possible for a destructible thing to escape destruction at a given
time, whereas it is not possible for it to escape absolutely. In the same
way also it is a good thing at certain places to follow see and such a
diet, e.g. in infected areas, though it is not a good thing absolutely.
Moreover, in certain places it is possible to live singly and alone, but
absolutely it is not possible to exist singly and alone. In the same way
also it is in certain places honourable to sacrifice one's father, e.g.
among the Triballi, whereas, absolutely, it is not honourable. Or possibly
this may indicate a relativity not to places but to persons: for it is
all the same wherever they may be: for everywhere it will be held honourable
among the Triballi themselves, just because they are Triballi. Again, at
certain times it is a good thing to take medicines, e.g. when one is ill,
but it is not so absolutely. Or possibly this again may indicate a relativity
not to a certain time, but to a certain state of health: for it is all
the same whenever it occurs, if only one be in that state. A thing is 'absolutely'
so which without any addition you are prepared to say is honourable or
the contrary. Thus (e.g.) you will deny that to sacrifice one's father
is honourable: it is honourable only to certain persons: it is not therefore
honourable absolutely. On the other hand, to honour the gods you will declare
to be honourable without adding anything, because that is honourable absolutely.
So that whatever without any addition is generally accounted to be honourable
or dishonourable or anything else of that kind, will be said to be so
'absolutely'.
Topics
By Aristotle
Book III
Part 1
The question which is the more desirable, or the better, of two or more
things, should be examined upon the following lines: only first of all
it must be clearly laid down that the inquiry we are making concerns not
things that are widely divergent and that exhibit great differences from
one another (for nobody raises any doubt whether happiness or wealth is
more desirable), but things that are nearly related and about which we
commonly discuss for which of the two we ought rather to vote, because
we do not see any advantage on either side as compared with the other.
Clearly, in such cases if we can show a single advantage, or more than
one, our judgement will record our assent that whichever side happens to
have the advantage is the more desirable.
First, then, that which is more lasting or secure is more desirable
than that which is less so: and so is that which is more likely to be chosen
by the prudent or by the good man or by the right law, or by men who are
good in any particular line, when they make their choice as such, or by
the experts in regard to any particular class of things; i.e. either whatever
most of them or what all of them would choose; e.g. in medicine or in carpentry
those things are more desirable which most, or all, doctors would choose;
or, in general, whatever most men or all men or all things would choose,
e.g. the good: for everything aims at the good. You should direct the argument
you intend to employ to whatever purpose you require. Of what is 'better'
or 'more desirable' the absolute standard is the verdict of the better
science, though relatively to a given individual the standard may be his
own particular science.
In the second place, that which is known as 'an x' is more desirable
than that which does not come within the genus 'x'-e.g. justice than a
just man; for the former falls within the genus 'good', whereas the other
does not, and the former is called 'a good', whereas the latter is not:
for nothing which does not happen to belong to the genus in question is
called by the generic name; e.g. a 'white man' is not 'a colour'. Likewise
also in other cases.
Also, that which is desired for itself is more desirable than that
which is desired for something else; e.g. health is more desirable than
gymnastics: for the former is desired for itself, the latter for something
else. Also, that which is desirable in itself is more desirable than what
is desirable per accidens; e.g. justice in our friends than justice in
our enemies: for the former is desirable in itself, the latter per accidens:
for we desire that our enemies should be just per accidens, in order that
they may do us no harm. This last principle is the same as the one that
precedes it, with, however, a different turn of expression. For we desire
justice in our friends for itself, even though it will make no difference
to us, and even though they be in India; whereas in our enemies we desire
it for something else, in order that they may do us no
harm.
Also, that which is in itself the cause of good is more desirable
than what is so per accidens, e.g. virtue than luck (for the former in
itself, and the latter per accidens, the cause of good things), and so
in other cases of the same kind. Likewise also in the case of the contrary;
for what is in itself the cause of evil is more objectionable than what
is so per accidens, e.g. vice and chance: for the one is bad in itself,
whereas chance is so per accidens.
Also, what is good absolutely is more desirable than what is good
for a particular person, e.g. recovery of health than a surgical operation;
for the former is good absolutely, the latter only for a particular person,
viz. the man who needs an operation. So too what is good by nature is more
desirable than the good that is not so by nature, e.g. justice than the
just man; for the one is good by nature, whereas in the other case the
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