Aristotle
and must then be resolved into their subordinate constituent
particulars, as far as the process of subdivision can be carried.[47]
[Footnote 44: Topic. I. xiv. p. 105, b. 4: [Greek: e)kle/gein mê\
mo/non ta\s ou)/sas e)ndo/xous, a)lla\ kai\ ta\s o(moi/as tau/tais.]]
[Footnote 45: Ibid. b. 17: [Greek: thei/ê ga\r a)/n tis to\ u(po/
tinos ei)rême/non e)ndo/xou].]
[Footnote 46: Ibid. b. 10: [Greek: o(/sa e)pi\ pa/ntôn ê)\ tô=n
plei/stôn phai/netai, lêpte/on ô(s a)rchê\n kai\ dokou=san the/sin;
tithe/asi ga\r oi( mê\ sunorô=ntes e)pi\ ti/nos ou)ch ou(/tôs.]]
[Footnote 47: Ibid. b. 31-37: [Greek: lêpte/on d' o(/ti ma/lista
katho/lou pa/sas ta\s prota/seis, kai\ tê\n mi/an polla\s
poiête/on--diairete/on, e(/ôs a)\n e)nde/chêtai diairei=n], &c.]
2. The propositions having been got together, they must be examined
in order to find out Equivocation or double meaning of terms. There
are various ways of going about this task. Sometimes the same
predicate is applied to two different subjects, but in different
senses; thus, courage and justice are both of them good, but in a
different way. Sometimes the same predicate is applied to two
different classes of subjects, each admitting of being defined; thus,
health is good in itself, and exercise is good as being among those
things that promote health.[48] Sometimes the equivocal meaning of a
term is perceived by considering its contrary; if we find that it has
two or more distinct contraries, we know at once that it has
different meanings. Sometimes, though there are not two distinct
contraries, yet the mere conjunction of the same adjective with two
substantives shows us at once that it cannot mean the same in
both[49] ([Greek: leukê\ phônê/--leuko\n chrô=ma]). In one sense, the
term may have an assignable contrary, while in another sense it may
have no contrary; showing that the two senses are distinct: for
example, the pleasure of drinking has for its contrary the pain of
thirst; but the pleasure of scientifically contemplating that the
diagonal of a square is incommensurable with the side, has no
contrary; hence, we see that pleasure is an equivocal term.[50] In
one sense, there may be a term intermediate between the two
contraries; in another sense, there may be none; or there may be two
distinct intermediate terms for the two distinct senses; or there may
be several intermediate terms in one of the senses, and only one or
none in the other: in each of these ways the equivocation is
revealed.[51] We must look also to the contradictory opposite (of a
term), which may perhaps have an obvious equivocation of meaning;
thus, [Greek: mê\ ble/pein] means sometimes to be blind, sometimes
not to be seeing actually, whence we discover that [Greek: ble/pein]
also has the same equivocation.[52] If a positive term is equivocal,
we know that the privative term correlating with it must also be
equivocal; thus, [Greek: to\ ai)stha/nesthai] has a double sense,
according as we speak with reference to mind or body; and this will
be alike true of the correlating privative--[Greek: to\ a)nai/sthêton
ei)=nai].[53] Farther, an equivocal term will have its derivatives
equivocal in the same manner; and conversely, if the derivative be
equivocal, the radical will be so likewise.[54] The term must also be
looked at in reference to the ten Categories: if its meanings fall
under more than one Category, we know that it is equivocal.[55] If it
comprehends two subjects which are not in the same genus, or in
genera not subordinate one to the other, this too will show that it
is equivocal.[56] The contrary, also, of the term must be looked at
with a view to the same inference.[57]
[Footnote 48: Topic. I. xv. p. 106, a. 1-8: [Greek: to\ de\
posachô=s, pragmateute/on mê\ mo/non o(/sa le/getai kath' e(/teron
tro/pon, a)lla\ kai\ tou\s lo/gous au)tôn peirate/on a)podido/nai.]]
[Footnote 49: Ibid. a. 9-35.]
[Footnote 50: Ibid. a. 36.]
[Footnote 51: Ibid. b. 4.]
[Footnote 52: Ibid. b. 13-20.]
[Footnote 53: Ibid. b. 21-28.]
[Footnote 54: Ibid. b. 28.]
[Footnote 55: Ibid. p. 107, a. 3-17.]
[Footnote 56: Ibid. a. 18.]
[Footnote 57: Ibid. a. 32-35.]
Again, it will be useful to bring together the same term in two
different conjunctions, and to compare the definitions of the two.
Define both of them, and then deduct what is peculiar to each
_definitum_: if the remainder be different, the term will be
equivocal; if the remainder be the same, the term will be univocal.
Thus, [Greek: leuko\n sô=ma] will be defined, a body having such and
such a colour: [Greek: leukê\ phônê/], a voice easily and distinctly
heard: deduct [Greek: sô=ma] from the first definition, and [Greek:
phônê\] from the second, the remainder will be totally disparate;
therefore, the term [Greek: leuko/n] is equivocal.[58] Sometimes,
also, the ambiguity may be found in definitions themselves, where the
same term is used to explain subjects that are not the same; whether
such use is admissible, has to be considered.[59] If the term be
univocal, two conjunctions of it may always be compared as to greater
or less, or in respect of likeness; whenever this cannot be, the term
is equivocal.[60] If, again, the term is used as a differentia for
two genera quite distinct and independent of each other, it must be
equivocal; for genera that are unconnected and not subordinate one to
the other, have their differentiæ also disparate.[61] And,
conversely, if the term be such that the differentiæ applied to it
are disparate, we may know it to be an equivocal term. The like, if
the term be used as a species in some of its conjunctions, and as a
differentia in others.[62]
[Footnote 58: Topic. I. xv. p. 107, a. 36-b. 3.]
[Footnote 59: Ibid. b. 8.]
[Footnote 60: Ibid. b. 13-18: [Greek: e)/ti ei) mê\ sumblêta\ kata\
to\ ma=llon ê)\ o(moi/ôs,--to\ ga\r sunô/numon pa=n sumblêto/n.]]
[Footnote 61: Ibid. b. 19-26.]
[Footnote 62: Ibid. b. 27-37.]
3. Aristotle has thus indicated, at considerable length, the points
to be looked for when we are examining whether a term is univocal or
equivocal. He is more concise when he touches on the last two out of
the four helps ([Greek: o)/rgana]) enumerated for supplying
syllogisms when needed,--viz. the study of Differences and of
Resemblances. In regard to the study of Differences, standing third,
while he remarks that, where these are wide and numerous, they are
sure without any precept to excite our attention, he advises that we
should study the differences of subjects that are nearly
allied,--those within the same genus, or comprehended in genera not
much removed from one another, such as, the distinction between
sensible perception and science. But he goes into no detail.[63]
[Footnote 63: Ibid. xvi. p. 107, b. 39.]
4. In regard to the study of Resemblances, he inverts the above
precept, and directs us to note especially the points of resemblance
between subjects of great apparent difference.[64] We must examine
what is the quality common to all species of the same genus--man,
horse, dog, &c.; for it is in this that they are similar. We may also
compare different genera with each other, in respect to the analogies
that are to be found in each: _e.g._, as science is to the
cognizable, so is perception to the perceivable; as sight is in the
eye, so is intellection in the soul; as [Greek: galê/nê] is in the
sea, so is [Greek: nênemi/a] in the air.[65]
[Footnote 64: Ibid. xvii. p. 108, a. 12: [Greek: ma/lista d' e)n
toi=s polu\ diestô=si gumna/zesthai dei=; r(a=|on ga\r e)pi\ tô=n
loipô=n dunêso/metha ta\ o(/moia sunora=n.]]
[Footnote 65: Topic. I. xvii. p. 108, a. 7.]
Such are the four distinct helps, towards facility of syllogizing,
enumerated by Aristotle. It will be observed that the third and
fourth (study of Resemblances and Differences) bear more upon matters
of fact and less upon words; while the second ([Greek: to\
posachô=s]), though doubtless also bearing on matters of fact and
deriving from thence its main real worth, yet takes its departure
from terms and propositions, and proceeds by comparing multiplied
varieties of these in regard to diversity of meaning. Upon this
ground it is, apparently, that Aristotle has given so much fuller
development to the second head than to the third and fourth; for, in
the Topica, he is dealing with propositions and
counter-propositions--with opinions and counter-opinions, not with
science and truth.
He proceeds to indicate the different ways in which these three helps
(the second, third, and fourth) further the purpose of the
dialectician--respondent as well as assailant. Unless the different
meanings of the term be discriminated, the respondent cannot know
clearly what he admits or what he denies; he may be thinking of
something different from what the assailant intends, and the
syllogisms constructed may turn upon a term only, not upon any
reality.[66] The respondent will be able to protect himself better
against being driven into contradiction, if he can distinguish the
various meanings of the same term; for he will thus know whether the
syllogisms brought against him touch the real matter which he has
admitted.[67] On the other hand, the assailant will have much
facility in driving his opponent into contradiction, if he (the
assailant) can distinguish the different meanings of the term, while
the respondent cannot do so; in those cases at least where the
proposition is true in one sense of the term and false in
another.[68] This manner of proceeding, however, is hardly consistent
with genuine Dialectic. No dialectician ought ever to found his
interrogations and his arguments upon a mere unanalysed term, unless
he can find absolutely nothing else to say in the debate.[69]
[Footnote 66: Ibid. xviii. p. 108, a. 22.]
[Footnote 67: Ibid. a. 26: [Greek: chrê/simon de\ kai\ pro\s to\ mê\
paralogisthê=nai kai\ pro\s to\ paralogi/sasthai. ei)do/tes ga\r
posachô=s le/getai ou) mê\ paralogisthô=men, a)ll' ei)dê/somen e)a\n
mê\ pro\s to\ au)to\ to\n lo/gon poiê=tai o( e)rôtô=n.]]
[Footnote 68: Ibid. a. 29: [Greek: au)toi/ te e)rôtô=ntes
dunêso/metha paralogi/sasthai e)a\n mê\ tugcha/nê| ei)dô\s o(
a)pokrino/menos posachô=s le/getai; tou=to d' ou)k e)pi\ pa/ntôn
dunato/n, a)ll' o(/tan ê)=| tô=n pollachô=s legome/nôn ta\ me\n
a)lêthê=, ta\ de\ pseudê=.]]
[Footnote 69: Topic. I. xviii. p. 108, a. 34: [Greek: dio\ pantelô=s
eu)labête/on toi=s dialektikoi=s to\ toiou=nton, to\ pro\s tou)/noma
diale/gesthai, _e)a\n mê/ tis a)/llôs e)xadunatê=| peri\ tou=
prokeime/nou diale/gesthai_.]]
The third help (an acquaintance with Differences) will be of much
avail on all occasions where we have to syllogize upon Same and
Different, and where we wish to ascertain the essence or definition
of any thing; for we ascertain this by exclusion of what is foreign
thereunto, founded on the appropriate differences in each case.[70]
[Footnote 70: Ibid. b. 2.]
Lastly, the fourth help (the intelligent survey of Resemblances)
serves us in different ways:--(1) Towards the construction of
inductive arguments; (2) Towards syllogizing founded upon assumption;
(3) Towards the declaration of definitions. As to the inductive
argument, it is founded altogether on a repetition of similar
particulars, whereby the universal is obtained.[71] As to the
syllogizing from an assumption, the knowledge of resemblances is
valuable, because we are entitled to assume, as an _Endoxon_ or a
doctrine conformable to common opinion, that what happens in any one
of a string of similar cases will happen also in all the rest. We lay
down this as the major proposition of a syllogism; and thus, if we
can lay hold of any one similar case, we can draw inference from it
to the matter actually in debate.[72] Again, as to the declaration of