Aristotle
and two contraries may both be false. You are warranted in declaring
only the contradictory negative, Not all men are wise.[29]
[Footnote 29: Aristot. De Interpret. p. 20, a. 16-30.]
Neither the indefinite noun ([Greek: ou)k a)/nthrôpos]) nor the
indefinite verb ([Greek: ou) tre/chei--ou) di/kaios]) is a real and
true negation, though it appears to be such. For every negation ought
to be either true or false; but _non homo_, if nothing be appended to
it, is not more true or false (indeed less so) than _homo_.[30]
[Footnote 30: Ibid. a. 31, seq.]
The transposition of substantive and adjective makes no difference in
the meaning of the phrase; _Est albus homo_ is equivalent to _Est
homo albus_. If it were not equivalent, there would be two negations
corresponding to the same affirmation; but we have shown that there
can be only one negation corresponding to one affirmation, so as to
make up an _Antiphasis_.[31]
[Footnote 31: Ibid. b. 1-12. That [Greek: e)sti\ leuko\s
a)/nthrôpos], and [Greek: e)sti\n a)/nthrôpos leuko/s], mean exactly
the same, neither more nor less--we might have supposed that
Aristotle would have asserted without any proof; that he would have
been content [Greek: a)po\ tô=n pragma/tôn pistou=sthai] (to use the
phrase of Ammonius in a portion of the Scholia, p. 121, a. 27). But
he prefers to deduce it as a corollary from a general doctrine much
less evident than the statement itself; and after all, his deduction
is not conclusive, as Waitz has already remarked (ad Organ. I. p.
351).]
In one and the same proposition, it is indispensable that the subject
be one and the predicate one; if not, the proposition will not be
one, but two or more. Both the subject and the predicate indeed may
consist of several words; but in each case the several words must
coalesce to make one total unity; otherwise the proposition will not
be one. Thus, we may predicate of man--_animal_, _bipes_,
_mansuetum_; but these three coalesce into one, so that the
proposition will be a single one. On the other hand the three terms
_homo_, _albus_, _ambulans_, do not coalesce into one; and therefore,
if we predicate all respecting the same subject, or if we affirm the
same predicate respecting all three, expressing them all by one word,
the proposition will not be one, but several.[32]
[Footnote 32: Aristot. De Interpr. p. 20, b. 13-22.]
Aristotle follows this up by a remark interesting to note, because we
see how much his generalities were intended to bear upon the actual
practice of his day, in regard to dialectical disputation. In
dialectic exercise, the respondent undertook to defend a thesis, so
as to avoid inconsistency between one answer and another, against any
questions which might be put by the opponent. Both the form of the
questions, and the form of the answers, were determined beforehand.
No question was admissible which tended to elicit information or a
positive declaration from the respondent. A proposition was tendered
to him, and he was required to announce whether he affirmed or denied
it. The question might be put in either one of two ways: either by
the affirmative alone, or by putting both the affirmative and the
negative; either in the form, Is Rhetoric estimable? or in the form,
Is Rhetoric estimable or not? To the first form the respondent
answered Yes or No: to the second form, he replied by repeating
either the affirmative or the negative, as he preferred. But it was
not allowable to ask him, _What_ is Rhetoric? so as to put him under
the necessity of enunciating an explanation of his own.[33]
[Footnote 33: See the Scholia of Ammonius, p. 127, Br.]
Under these canons of dialectic debate, each question was required to
be really and truly one, so as to admit of a definite answer in one
word. The questioner was either unfair or unskilful, if he wrapped up
two questions really distinct in the same word, and thus compelled
the respondent either to admit them both, or to deny them both, at
once. Against this inconvenience Aristotle seeks to guard, by
explaining what are the conditions under which one and the same word
does in fact include more than one question. He had before brought to
view the case of an equivocal term, which involves such duplication:
if _himation_ means both horse and man, it will often happen that
questions respecting _himation_ cannot be truly answered either by
Yes or No. He now brings to view a different case in which the like
ambiguity is involved. To constitute one proposition, it is essential
both that the subject should be one, and that the predicate should be
one; either of them indeed may be called by two or three names, but
these names must coalesce into one. Thus, _animal_, _bipes_,
_mansuetum_, coalesce into _homo_, and may be employed either as one
subject or as one predicate; but _homo_, _albus_, _ambulans_, do not
coalesce into one; so that if we say, _Kallias est homo, albus,
ambulans_, the proposition is not one but three.[34] Accordingly, the
respondent cannot make one answer to a question thus complicated. We
thus find Aristotle laying down principles--and probably no one had
ever attempted to do so before him--for the correct management of
that dialectical debate which he analyses so copiously in the Topica.
[Footnote 34: Aristot. De Interpret. p. 20, b. 2. seq.; Ammonius,
Schol. pp. 127-128, a. 21, Br. Compare De Sophist. Elench. p. 169, a.
6-15.]
There are cases (he proceeds to state) in which two predicates may be
truly affirmed, taken separately, respecting a given subject, but in
which they cannot be truly affirmed, taken together.[35] Kallias is a
_currier_, Kallias is _good_--both these propositions may be true;
yet the proposition, Kallias is a _good currier_, may not be true.
The two predicates are both of them accidental co-inhering in the
same individual; but do not fuse themselves into one. So, too, we may
truly say, Homer _is a poet_; but we cannot truly say, Homer
_is_.[36] We see by this last remark,[37] how distinctly Aristotle
assigned a double meaning to _est_: first, _per se_, as meaning
existence; next, relatively, as performing the function of copula in
predication. He tells us, in reply either to Plato or to some other
contemporaries, that though we may truly say, _Non-Ens est
opinabile_, we cannot truly say _Non-Ens est_, because the real
meaning of the first of these propositions is, **_Non-Ens est
opinabile non esse_.[38]
[Footnote 35: Aristot. De Interpr. p. 21, a. 7, seq.]
[Footnote 36: Ibid. a. 27.]
[Footnote 37: Compare Schol. (ad Anal. Prior. I.) p. 146, a. 19-27;
also Eudemi Fragment. cxiv. p. 167, ed. Spengel.
Eudemus considered [Greek: e)/stin] as one term in the proposition.
Alexander dissented from this, and regarded it as being only a copula
between the terms, [Greek: sunthe/seôs mênutiko\n mo/rion tô=n e)n
tê=| prota/sei o(/rôn.]]
[Footnote 38: Aristot. De Interpr. p. 21, a. 32; compare Rhetorica,
ii. p. 1402, a. 5. The remark of Aristotle seems to bear upon the
doctrine laid down by Plato in the Sophistes, p. 258--the close of
the long discussion which begins, p. 237, about [Greek: to\ mê\
o)/n], as Ammonius tells us in the Scholia, p. 112, b. 5, p. 129, b.
20, Br. Ammonius also alludes to the Republic; as if Plato had
delivered the same doctrine in both; which is not the fact. See
'Plato and the Other Companions of Sokrates,' vol. II. ch. xxvii. pp.
447-458, seq.]
Aristotle now discusses the so-called Modal Propositions--the
Possible and the Necessary. What is the appropriate form of
_Antiphasis_ in the case of such propositions, where _possible to
be_, or _necessary to be_, is joined to the simple _is_. After a
chapter of some length, he declares that the form of _Antiphasis_
suitable for the Simple proposition will not suit for a Modal
proposition; and that in the latter the sign of negation must be
annexed to the modal adjective--_possible_, _not possible_, _&c._ His
reasoning here is not merely involved, but substantially incorrect;
for, in truth, both in one and in the other, the sign of
contradictory negation ought to be annexed to the copula.[39] From
the _Antiphasis_ in Modals Aristotle proceeds to legitimate sequences
admissible in such propositions, how far any one of them can be
inferred from any other.[40] He sets out four tables, each containing
four modal determinations interchangeable with each other.
1.
1. Possible (physically) to be.
2. Possible (logically) to be.
3. Not impossible to be.
4. Not necessary to be.
2.
1. Possible (physically) not to be.
2. Possible (logically) not to be.
3. Not impossible not to be.
4. Not necessary not to be.
3.
1. Not possible (physically) to be.
2. Not possible (logically) to be.
3. Impossible to be.
4. Necessary not to be.
4.
1. Not possible (physically) not to be.
2. Not possible (logically) not to be.
3. Impossible not to be.
4. Necessary to be.
Aristotle canvasses these tables at some length, and amends them
partly by making the fourth case of the second table change place
with the fourth of the first.[41] He then discusses whether we can
correctly say that the _necessary to be_ is also _possible to be_. If
not, then we might say correctly that the _necessary to be_ is _not
possible to be_; for one side or other of a legitimate _Antiphasis_
may always be truly affirmed. Yet this would be absurd: accordingly
we must admit that the _necessary to be_ is also _possible to be_.
Here, however, we fall seemingly into a different absurdity; for the
_possible to be_ is also _possible not to be_; and how can we allow
that what is _necessary to be_ is at the same time _possible not to
be_? To escape from such absurdities on both sides, we must
distinguish two modes of the Possible: one, in which the affirmative
and negative are alike possible; the other in which the affirmative
alone is possible, because it is always and constantly realized. If a
man is actually walking, we know that it is possible for him to walk;
and even when he is not walking, we say the same, because we believe
that he may walk if he chooses. He is not always walking; and in his
case, as in all other intermittent realities, the affirmative and the
negative are alike possible. But this is not true in the case of
necessary, constant, and sempiternal realities. With them there is no
alternative possibility, but only the possibility of their doing or
continuing to do. The celestial bodies revolve, sempiternally and
necessarily; it is therefore possible for them to revolve; but there
is no alternative possibility; it is not possible for them not to
revolve. Perpetual reality thus includes the unilateral, but not the
bilateral, possibility.[42]
[Footnote 39: Aristot. De Interpret. p. 21, a. 34-p. 22, a. 13. See
the note of Waitz, ad Organ. I. p. 359, who points out the error of
Aristotle, partly indicated by Ammonius in the Scholia.
The rule does not hold in propositions with the sign of universality
attached to the subject; but it is at least the same for Modals and
Non-modals.]
[Footnote 40: Aristot. De Interpr. p. 22, a. 14-b. 28.]
[Footnote 41: Aristot. De Interpr. p. 22, b. 22, [Greek: lei/petai
toi/nun] &c.; Ammonius, Schol. p. 133, b. 5-27-36.
Aristotle also intimates (p. 23, a. 18) that it would be better to
reverse the order of the propositions in the tables, and to place the
Necessary before the Possible. M. Barthélemy St. Hilaire has inserted
(in the note to his Translation, p. 197) tables with this reversed
order.]
[Footnote 42: Aristot. De Interpret. p. 22, b. 29-p. 23, a. 15.]
Having thus stated that _possible to be_, in this unilateral and
equivocal sense but in no other, is a legitimate consequence of
_necessary to be_, Aristotle proceeds to lay down a tripartite