Aristotle
[Footnote 50: Aristot. De Interpret. p. 23, a. 32: [Greek: ta\ me\n
e)n tê=| phônê=| a)kolouthei= toi=s e)n tê=| dianoi/a|, e)kei= de\
e)nanti/a do/xa ê( tou= e)nanti/ou], &c. Ib. p. 24, b. 1: [Greek:
ô(/ste ei)/per e)pi\ do/xês ou(/tôs e)/chei, ei)si\ de\ ai( e)n tê=|
phônê=| katapha/seis kai\ a)popha/seis su/mbola tô=n e)n tê=|
psuchê=|, dê=lon o(/ti kai\ katapha/sei e)nanti/a me\n a)po/phasis
ê(/ peri\ tou= au)tou= katho/lou], &c. Ib. p. 17, a. 22: [Greek:
e)/sti de\ ê( a(plê= a)po/phansis phônê\ sêmantikê\ peri\ tou=
u(pa/rchein ti ê)\ mê\ u(pa/rchein], &c.]
[Footnote 51: Ibid. p. 17, a. 5. [Greek: oi( me\n ou)=n a)/lloi
(lo/goi) a)phei/sthôsan; r(êtorikê=s ga\r ê)\ poiêtikê=s oi)keiote/ra
ê( ske/psis; o( de\ a)pophantiko\s tê=s nu=n theôri/as.]]
[Footnote 52: Ammonius (in the Scholia on De Interpret. p. 130, a.
16, seq., Brand.) ranks all modal propositions under the same
category, and considers the number of them to be, not indeed
infinite, but very great. He gives as examples: "The moon changes
_fast_; Plato loves Dion _vehemently_." Sir W. Hamilton adopts the
same view as Ammonius: "Modes may be conceived without end--all must
be admitted, if any are; the line of distinction attempted to be
drawn is futile." (Discussions on Phil. ut sup. p. 145.) On the other
hand, we learn from Ammonius that most of the Aristotelian
interpreters preceding him reckoned the simple proposition [Greek:
to\ u(pa/rchein] as a modal; and Aristotle himself seems so to
mention it (Analytica Priora, I. ii. p. 25, a. 1); besides that he
enumerates _true_ and _false_, which undoubtedly attach to [Greek:
to\ u(pa/rchein], as examples of modes (De Interpret. c. 12, p. 22,
a. 13). Ammonius himself protests against this doctrine of the former
interpreters.
Mr. John Stuart Mill (System of Logic, Bk. I. ch. iv. s. 2) says:--"A
remark of a similar nature may be applied to most of those
distinctions among propositions which are said to have reference to
their _modality_; as difference of tense or time; the sun _did_ rise,
_is_ rising, _will_ rise. . . . The circumstance of time is properly
considered as attaching to the copula, which is the sign of
predication, and not to the predicate. If the same cannot be said of
such modifications as these, Cæsar is _perhaps_ dead; it is
_possible_ that Cæsar is dead; it is only because these fall together
under another head; being properly assertions not of anything
relating to the fact itself, but of the state of our own mind in
regard to it; namely, our absence of disbelief of it. Thus, _Cæsar
may be dead_, means, _I am not sure that Cæsar is alive_."
I do not know whether Mr. Mill means that the function of the copula
is different in these problematical propositions, from what it is in
the categorical propositions: I think there is no difference. But his
remark that the problematical proposition is an assertion of the
state of our minds in regard to the fact, appears to me perfectly
just. Only, we ought to add, that this is equally true about the
categorical proposition. It is equally true about all the three
following propositions:--1. The three angles of a triangle may or may
not be equal to two right angles. 2. The three angles of a triangle
are equal to two right angles. 3. The three angles of a triangle are
necessarily equal to two right angles. In each of these three
propositions, an assertion of the state of our minds is involved, and
a different state of mind in each. This is the subjective aspect of
the proposition; it belongs to the form rather than to the matter,
and may be considered as a mode. The commentators preceding Ammonius
did so consider it, and said that the categorical proposition had its
mode as well as the others. Ammonius differed from them, treating the
categorical as having no mode--as the standard unit or point of
departure.
The propositions now known as Hypothetical and Disjunctive, which may
also be regarded as in a certain sense Modals, are not expressly
considered by Aristotle. In the Anal. Prior. I. xliv. p. 50 a. 16-38,
he adverts to hypothetical syllogisms, and intimates his intention of
discussing them more at length: but this intention has not been
executed, in the works that we possess.]
In every complete theory of enunciative speech, these modal
propositions deserve to be separately explained, both in their
substantive meaning and in their relation to other propositions.
Their characteristic property as Modals belongs to _form_ rather than
to _matter_; and Aristotle ought not to be considered as
unphilosophical for introducing them into the Organon, even if we
adopt the restricted view of Logic taken by Sir W. Hamilton, that it
takes no cognizance of the matter of propositions, but only of their
form. But though I dissent from Hamilton's criticisms on this point,
I do not concur with the opposing critics who think that Aristotle
has handled the Modal Propositions in a satisfactory manner. On the
contrary, I think that the equivocal sense which he assigns to the
Potential or Possible, and his inconsistency in sometimes admitting,
sometimes denying, a Potential that is always actual, and a Potential
that is never actual--are serious impediments to any consistent
Logic. The Problematical Proposition does not admit of being cut in
half; and if we are to recognize a _necessary_ Possible, or an
_impossible_ Possible, we ought to find different phrases by which to
designate them.
We must observe that the distinction of Problematical and Necessary
Propositions corresponds, in the mind of Aristotle, to that capital
and characteristic doctrine of his Ontology and Physics, already
touched on in this chapter. He thought, as we have seen, that in the
vast circumferential region of the Kosmos, from the outer sidereal
sphere down to the lunar sphere, celestial substance was a necessary
existence and energy, sempiternal and uniform in its rotations and
influence; and that through its beneficent influence, pervading the
concavity between the lunar sphere and the terrestrial centre (which
included the four elements with their compounds) there prevailed a
regularizing tendency called Nature: modified, however, and partly
counteracted by independent and irregular forces called Spontaneity
and Chance, essentially unknowable and unpredictable. The irregular
sequences thus named by Aristotle were the objective correlate of the
Problematical Proposition in Logic. In these sublunary sequences, as
to future time, _may or may not_ was all that could be attained, even
by the highest knowledge; certainty, either of affirmation or
negation, was out of the question. On the other hand, the necessary
and uniform energies of the celestial substance, formed the objective
correlate of the Necessary Proposition in Logic; this substance was
not merely an existence, but an existence necessary and unchangeable.
I shall say more on this when I come to treat of Aristotle as a
kosmical and physical philosopher; at present it is enough to remark
that he considers the Problematical Proposition in Logic to be not
purely subjective, as an expression of the speaker's ignorance, but
something more, namely, to correlate with an objective essentially
unknowable to all.
The last paragraph of the treatise De Interpretatione discusses the
question of Contraries and Contradictories, and makes out that the
greatest breadth of opposition is that between a proposition and its
contradictory (Kallias is just--Kallias is not just), not that
between, a proposition and what is called its contrary (Kallias is
just--Kallias is unjust); therefore, that according to the definition
of contrary, the true contrary of a proposition is its
contradictory.[53] This paragraph is not connected with that which
precedes; moreover, both the reasoning and the conclusion differ from
what we read as well in this treatise as in other portions of
Aristotle. Accordingly, Ammonius in the Scholia, while informing us
that Porphyry had declined to include it in his commentary, intimates
also his own belief that it is not genuine, but the work of another
hand. At best (Ammonius thinks), if we must consider it as the work
of Aristotle, it has been composed by him only as a dialectical
exercise, to debate an unsettled question.[54] I think the latter
hypothesis not improbable. The paragraph has certainly reference to
discussions which we do not know, and it may have been composed when
Aristotle had not fully made up his mind on the distinction between
Contrary and Contradictory. Considering the difficult problems that
he undertook to solve, we may be sure that he must have written down
several trains of thought merely preliminary and tentative. Moreover,
we know that he had composed a distinct treatise 'De Oppositis,'[55]
which is unfortunately lost, but in which he must have included this
very topic--the distinction between Contrary and Contradictory.
[Footnote 53: Aristot. De Interpr. p. 23, a. 27, seq.]
[Footnote 54: Scholia ad Arist. pp. 135-139, Br. [Greek: gumna/sai
mo/non boulêthe/ntos tou\s e)ntugcha/nontas pro\s tê\n e)pi/krisin
tô=n pithanô=s me\n ou) me/ntoi a)lêthô=s legome/nôn lo/gôn] &c. (p.
135, b. 15; also p. 136, a. 42).]
[Footnote 55: Scholia ad Categorias, p. 83, a. 17-19, b. 10, p. 84,
a. 29, p. 86, b. 42, p. 88, a. 30. It seems much referred to by
Simplikius, who tells us that the Stoics adopted most of its
principles (p. 83, a. 21, b. 7).]
Whatever may have been the real origin and purpose of this last
paragraph, I think it unsuitable as a portion of the treatise De
Interpretatione. It nullifies, or at least overclouds, one of the
best parts of that treatise, the clear determination of _Anaphasis_
and its consequences.
If, now, we compare the theory of the Proposition as given by
Aristotle in this treatise, with that which we read in the Sophistes
of Plato, we shall find Plato already conceiving the proposition as
composed indispensably of noun and verb, and as being either
affirmative or negative, for both of which he indicates the technical
terms.[56] He has no technical term for either subject or predicate;
but he conceives the proposition as belonging to its subject:[57] we
may be mistaken in the predicates, but we are not mistaken in the
subject. Aristotle enlarges and improves upon this theory. He not
only has a technical term for affirmation and negation, and for
negative noun and verb, but also for subject and predicate; again,
for the mode of signification belonging to noun and verb, each
separately, as distinguished from the mode of signification belonging
to them conjointly, when brought together in a proposition. He
follows Plato in insisting upon the characteristic feature of the
proposition--aptitude for being true or false; but he gives an ampler
definition of it, and he introduces the novel and important
distribution of propositions according to the quantity of the
subject. Until this last distribution had been made, it was
impossible to appreciate the true value and bearing of each
_Antiphasis_ and the correct language for expressing it, so as to say
neither more nor less. We see, by reading the Sophistes, that Plato
did not conceive the _Antiphasis_ correctly, as distinguished from
Contrariety on the one hand, and from mere Difference on the other.
He saw that the negative of any proposition does not affirm the
contrary of its affirmative; but he knew no other alternative except
to say, that it affirms only something different from the
affirmative. His theory in the Sophistes recognizes nothing but
affirmative propositions, with the predicate of contrariety on one
hand, or of difference on the other;[58] he ignores, or jumps over,
the intermediate station of propositions affirming nothing at all,
but simply denying a pre-understood affirmative. There were other