Aristotle
universals. Review them not at once as separate individuals, but as
comprised in subordinate genera and species; beginning from the
highest, and descending down to the lowest species which is not
farther divisible except into individuals. Thus, if the thesis
propounded be, The cognition of opposites is one and the same
cognition; you will investigate whether this can be truly predicated
respecting all the primary species of _Opposita_: respecting _Relata_
and _Correlata_, respecting Contraries, respecting Contradictories,
respecting _Habitus_ and _Privatio_. If, by going thus far, you
obtain no result favourable to your purpose,[84] you must proceed
farther, and subdivide until you come to the lowest species:--Is the
cognition of just and unjust one and the same? that of double and
half? of sight and blindness? of existence and non-existence? If in
all, or in any one, of these cases you can show that the universal
thesis does not hold, you will have gained your point of refuting it.
On the other hand, if, when you have enumerated many particulars, the
thesis is found to hold in all, the respondent is entitled to require
you to grant it as an universal proposition, unless you can produce a
satisfactory counter-example. If you decline this challenge, you will
be considered an unreasonable debater.[85]
[Footnote 84: Topic. II. ii. p. 109, b. 20: [Greek: ka)\n e)pi\
tou/tôn mê/pô phanero\n ê)=|, pa/lin tau=ta diairete/on me/chri tô=n
a)to/môn, oi(=on ei) tô=n dikai/ôn kai\ a)di/kôn], &c.]
[Footnote 85: Ibid. b. 25-30. [Greek: e)a\n ga\r mêde/teron tou/tôn
poiê=|, a)/topos phanei=tai mê\ tithei/s.]]
3. You will find it useful to define both the accident predicated in
the thesis, and the subject respecting which it is predicated, or at
least one of them: you will see then whether these definitions reveal
anything false in the affirmation of the thesis. Thus, if the thesis
affirms that it is possible to do injustice to a god, you will define
what is meant by doing injustice. The definition is--hurting
intentionally: you can thus refute the thesis by showing that no
injustice to a god can possibly be done; for a god cannot be
hurt.[86] Or let the thesis maintained be, The virtuous man is
envious. You define envy, and you find that it is--vexation felt by
reason of the manifest success of some meritorious man. Upon this
definition it is plain that the virtuous man cannot feel envy: he
would be worthless, if he did feel it. Perhaps some of the terms
employed in your definition may themselves require definition; if so,
you will repeat the process of defining until you come to something
plain and clear.[87] Such an analysis will often bring out some error
at first unperceived in the thesis.
[Footnote 86: Topic. II. ii. p. 109, b. 34: [Greek: ou) ga\r
e)nde/chetai bla/ptesthai to\n theo/n.]]
[Footnote 87: Ibid. p. 110, a. 4: [Greek: lamba/nein de\ kai\ a)nti\
tô=n e)n toi=s lo/gois o)noma/tôn lo/gous, kai\ mê\ a)phi/stasthai
e(/ôs a)\n ei)s gnô/rimon e)/lthê|.]]
4. It will be advisable, both for assailant and respondent, to
discriminate those cases in which the authority of the multitude is
conclusive from those in which it is not. Thus, in regard to the
meaning of terms and in naming objects, we must speak like the
multitude; but, when the question is as to what objects deserve to be
denominated so and so, we must not feel bound by the multitude, if
there be any special dissentient authority.[88] That which produces
good health we must call wholesome, as the multitude do; but, in
calling this or that substance wholesome, the physician must be our
guide.
[Footnote 88: Ibid. a. 14-22.]
5. Aristotle gives more than one suggestion as to those cases in
which the terms of the thesis have a double or triple sense, yet in
which the thesis is propounded either as an universal affirmative or
as an universal negative. If the respondent is himself not aware of
the double sense of his thesis, while you (the questioner) are aware
of it, you will prove the point which you are seeking to establish
against him in one or other of the two senses, if you cannot prove it
in both. If he is aware of it in the double sense, he will insist
that you have chosen the sense which he did not intend.[89] This mode
of procedure will be available to the respondent as well as to you;
but it will be harder to him, since his thesis is universal. For, in
order to make good an universal thesis, he must obtain your assent to
a preliminary assumption or convention, that, if he can prove it in
one sense of the terms, it shall be held proved in both; and, unless
the proposition be so plausible that you are disposed to grant him
this, he will not succeed in the procedure.[90] But you on your side,
as refuting, do not require any such preliminary convention or
acquiescence; for, if you prove the negative in any single case, you
succeed in overthrowing the universal affirmative, while, if you
prove the affirmative in any single case, you succeed in overthrowing
the universal negative.[91] Such procedure, however, is to be adopted
only when you can find no argument applicable to the equivocal thesis
in all its separate meanings; this last sort of argument, wherever it
can be found, being always better.[92]
[Footnote 89: Topic. II. iii. p. 110, a. 24.]
[Footnote 90: Ibid. a. 37: [Greek: kataskeua/zousi de\
prodiomologête/on o(/ti ei) o(tô|ou=n u(pa/rchei, panti\ u(pa/rchei,
a)\n pithano\n ê)=| to\ a)xi/ôma; ou) ga\r a)po/chrê pro\s to\
dei=xai o(/ti panti\ u(pa/rchei to\ e)ph' e(no\s dialechthê=nai.]]
[Footnote 91: Topic. II. iii. p. 110, a. 32: [Greek: plê\n
a)naskeua/zonti me\n ou)de\n dei= e)x o(mologi/as diale/gesthai].]
[Footnote 92: Ibid. b. 4.]
In cases where the double meaning is manifest, the two meanings must
be distinguished by both parties, and the argument conducted
accordingly. Where the term has two or more meanings (not equivocal
but) related to each other by analogy, we must deal with each of
these meanings distinctly and separately.[93] If our purpose is to
refute, we select any one of them in which the proposition is
inadmissible, neglecting the others: if our purpose is to prove, we
choose any one in which the proposition is true, neglecting the
others.[94]
[Footnote 93: Topic. II. iii. p. 110, b. 16-p. 111, a. 7. This
_locus_ is very obscurely stated by Aristotle.]
[Footnote 94: Ibid. p. 110, b. 29-32: [Greek: e)a\n boulô/metha
kataskeua/sai, ta\ toiau=ta prooiste/on o(/sa e)nde/chetai, kai\
diairete/on _ei)s tau=ta mo/non_ o(/sa kai\ chrê/sima pro\s to\
kataskeua/sai; a)\n d' a)naskeua/sai, o(/sa mê\ e)nde/chetai, _ta\
de\ loipa\ paraleipte/on_.]
Aristotle's precepts indicate the way of managing the debate _with a
view to success._]
6. Observe that a predicate which belongs to the genus does not
necessarily belong to any one of its species, but that any predicate
which belongs to one of the species does belong also to the genus; on
the other hand, that any predicate which can be denied of the genus
may be denied also of all its contained species, but that any
predicate which can be denied of some one or some portion of the
contained species cannot for that reason be denied of the genus. You
may thus prove from one species to the genus, and disprove from the
genus to each one species; but not _vice versâ_. Thus, if the
respondent grants that there exist cognitions both estimable and
worthless, you are warranted in inferring that there exist habits of
mind estimable and worthless; for cognition is a species under the
genus habit of mind. But if the negative were granted, that there
exist no cognitions both estimable and worthless, you could not for
that reason infer that there are no habits of mind estimable and
worthless. So, if it were granted to you that there are judgments
correct and erroneous, you could not for that reason infer that there
were perceptions of sense correct and erroneous; perceiving by sense
being a species under the genus judging. But, if it were granted that
there were no judgments correct and erroneous, you might thence infer
the like negative about perceptions of sense.[95]
[Footnote 95: Topic. II. iv. p. 111, a. 14-32. [Greek: nu=n me\n
ou)=n e)k tou= ge/nous peri\ to\ ei)=dos ê( a)po/deixis; to\ ga\r
kri/nein ge/nos tou= ai)stha/nesthai; o( ga\r ai)sthano/menos kri/nei
pôs--o( me\n ou)=n pro/teros to/pos pseudê/s e)sti pro\s to\
kataskeua/sai, o( de\ deu/teros a)lêthê/s.--pro\s de\ to\
a)naskeua/zein o( me\n pro/teros a)lêthê/s, o( de\ deu/teros
pseudê/s.]
It is here a point deserving attention, that Aristotle ranks [Greek:
to\ ai)stha/nesthai] as a species under the genus [Greek: to\
kri/nein]. This is a notable circumstance in the Aristotelian
psychology.]
7. Keep in mind also that if there be any subject of which you can
affirm the genus, of that same subject you must be able to affirm one
or other of the species contained under the genus. Thus, if science
be a predicate applicable, grammar, music, or some other of the
special sciences must also be applicable: if any man can be called
truly a scientific man, he must be a grammarian, a musician, or some
other specialist. Accordingly, if the thesis set up by your
respondent be, The soul is moved, you must examine whether any one of
the known varieties of motion can be truly predicated of the soul,
_e.g._, increase, destruction, generation, &c. If none of these
special predicates is applicable to the soul, neither is the generic
predicate applicable to it; and you will thus have refuted the
thesis. This _locus_ may serve as a precept for proof as well as for
refutation; for, equally, if the soul be moved in any one species of
motion, it is moved, and, if the soul be not moved in any species of
motion, it is not moved.[96]
[Footnote 96: Topic. II. iv. p. 111, a. 33-b. 11.]
8. Where the thesis itself presents no obvious hold for
interrogation, turn over the various definitions that have been
proposed of its constituent terms; one or other of these definitions
will often afford matter for attack.[97] Look also to the antecedents
and consequents of the thesis--what must be assumed and what will
follow, if the thesis be granted. If you can disprove the consequent
of the proposition, you will have disproved the proposition itself.
On the other hand, if the antecedent of the proposition be proved,
the proposition itself will be proved also.[98] Examine also whether
the proposition be not true at some times, and false at other times.
The thesis, What takes nourishment grows necessarily, is true not
always, but only for a certain time: animals take nourishment during
all their lives, but grow only during a part of their lives. Or, if a
man should say that knowing is remembering, this is incorrect; for we
remember nothing but events past, whereas we know not only these, but
present and future also.[99]
[Footnote 97: Ibid. b. 12-16.]
[Footnote 98: Ibid. b. 17-23.]
[Footnote 99: Topic. II. iv. p. 111, b. 24-31.]
9. It is a sophistical procedure (so Aristotle terms it) to transfer
the debate to some point on which we happen to be well provided with
arguments, lying apart from the thesis defended. Such transfer,
however, may be sometimes necessary. In other cases it is not really
but only apparently necessary; in still other cases it is purely
gratuitous, neither really nor apparently necessary. It is really
necessary, when the respondent, having denied some proposition
perfectly relevant to his thesis, stands to his denial and accepts
the debate upon it, the proposition being one on which a good stock
of arguments may be found against him; also, when you are
endeavouring to disprove the thesis by an induction of negative
analogies.[100] It is only apparently, and not really, necessary, when