Aristotle
distinction which surprises us in this place. "It is plain from what
has been said that that which is by Necessity, is in Act or
Actuality; so that if things sempiternal are prior, Actuality is
prior to Possibility. Some things, like the first (or celestial)
substances, are Actualities without Possibility; others (the
generated and perishable substances) which are prior in nature but
posterior in generation, are Actualities along with Possibility;
while a third class are Possibilities only, and never come into
Actuality" (such as the largest number, or the least magnitude).[43]
[Footnote 43: Ibid. p. 23, a. 21-26.]
Now the sentence just translated (enunciating a doctrine of
Aristotle's First Philosophy rather than of Logic) appears decidedly
to contradict what he had said three lines before, viz., that in one
certain sense, the _necessary to be_ included and implied the
_possible to be_; that is, a possibility or potentiality unilateral
only, not bilateral; for we are here told that the celestial
substance is Actuality without Possibility (or Potentiality), so that
the unilateral sense of this last term is disallowed. On the other
hand, a third sense of the same term is recognized and distinguished;
a sense neither bilateral nor unilateral, but the negation of both.
This third sense is hardly intelligible, giving as it does an
_impossible_ Possible; it seems a self-contradictory description.[44]
At best, it can only be understood as a limit in the mathematical
sense; a terminus towards which potentiality may come constantly
nearer and nearer, but which it can never reach. The first, or
bilateral potentiality, is the only sense at once consistent,
legitimate, and conformable to ordinary speech. Aristotle himself
admits that the second and third are equivocal meanings,[45]
departing from the first as the legitimate meaning; but if equivocal
departure to so great an extent were allowed, the term, put to such
multifarious service, becomes unfit for accurate philosophical
reasoning. And we find this illustrated by the contradiction into
which Aristotle himself falls in the course of a few lines. The
sentence of First Philosophy (which I translated in the last page) is
a correction of the logical statement immediately preceding it, in so
far as it suppresses the _necessary_ Possible, or the unilateral
potentiality. But on the other hand the same sentence introduces a
new confusion by its third variety--the _impossible_ Potential,
departing from all clear and consistent meaning of potentiality, and
coinciding only with the explanation of _Non-Ens_, as given by
Aristotle elsewhere.[46]
[Footnote 44: M. Barthélemy St. Hilaire, in the note to his
translation (p. 197) calls it justly--"le possible qui n'est jamais;
et qui par cela même, porte en lui une sorte d'impossibilité." It
contradicts both the two explanations of [Greek: dunato\n] which
Aristotle had given a few lines before. 1. [Greek: dunato\n o(/ti
e)nergei=]. 2. [Greek: dunato\n o(/ti e)nergê/seien a)/n] (p. 23, a.
10).]
[Footnote 45: Aristot. De Interpr. p. 23, a. 5. [Greek: tou=to me\n
tou/tou cha/rin ei)/rêtai, o(/ti ou) pa=sa du/namis tô=n
a)ntikeime/nôn, ou)d' o(/sai le/gontai kata\ to\ au)to\ ei)=dos.
e)/niai de\ duna/meis o(mô/numoi/ ei)sin; to\ ga\r dunato\n ou)ch
a(plô=s le/getai, a)lla\ to\ me\n o(/ti a)lêthe\s ô(s e)nergei/a|
o)/n], &c.
If we read the thirteenth chapter of Analytica Priora I. (p. 32, a.
18-29) we shall see that [Greek: to\ e)ndecho/menon] is declared to
be [Greek: ou)k a)nagkai=on], and that in the definition of [Greek:
to\ e)ndecho/menon], the words [Greek: ou(= mê\ o)/ntos a)nagkai/ou]
are expressly inserted. When [Greek: to\ a)nagkai=on] is said [Greek:
e)nde/chesthai], this is said only in an _equivocal_ sense of [Greek:
e)nde/chesthai--to\ ga\r a)nagkai=on _o(mônu/môs_ e)nde/chesthai
le/gomen.]
On the meaning of [Greek: to\ e)ndecho/menon], translated above, in
the table, "possible (logically) to be," and its relation to [Greek:
to\ dunato/n], see Waitz, ad Organ. I. pp. 375-8. Compare Prantl.
Gescht. der Logik, I. pp. 166-8.]
[Footnote 46: Aristot. De Interpr. p. 21, a. 32: [Greek: to\ de\ mê\
o)/n, o(/ti doxasto/n, ou)k a)lêthe\s ei)pei=n o)/n ti; do/xa ga\r
au)tou= ou)k e)/stin o(/ti e)/stin, a)ll' o(/ti ou)k e)/stin. To\ mê\
o)/n] is the true description of that which Aristotle improperly
calls [Greek: du/namis ê(\ ou)de/pote e)ne/rgeia/ e)stin].
The triple enumeration given by Aristotle (1. Actuality without
Potentiality. 2. Actuality with Potentiality. 3. Potentiality without
Actuality) presents a neat symmetry which stands in the place of
philosophical exactness.]
The contrast of Actual and Potential stands so prominently forward in
Aristotle's First Philosophy, and is, when correctly understood, so
valuable an element in First Philosophy generally, that we cannot be
too careful against those misapplications of it into which he himself
sometimes falls. The sense of Potentiality, as including the
alternative of either affirmative or negative--_may be or may not
be_--is quite essential in comprehending the ontological theories of
Aristotle; and when he professes to drop the _may not be_ and leave
only the _may be_, this is not merely an equivocal sense of the word,
but an entire renunciation of its genuine sense. In common parlance,
indeed, we speak elliptically, and say, _It may be_, when we really
mean, _It may or may not be_. But the last or negative half, though
not expressly announced, is always included in the thought and belief
of the speaker and understood by the hearer.[47]
[Footnote 47: See Trendelenburg ad Aristot. De Animâ, pp. 303-307.]
Many logicians, and Sir William Hamilton very emphatically, have
considered the Modality of propositions as improper to be included in
the province of Logic, and have treated the proceeding of Aristotle
in thus including it, as one among several cases in which he had
transcended the legitimate boundaries of the science.[48] This
criticism, to which I cannot subscribe, is founded upon one peculiar
view of the proper definition and limits of Logic. Sir W. Hamilton
lays down the limitation peremptorily, and he is warranted in doing
this for himself; but it is a question about which there has been
great diversity of view among expositors, and he has no right to
blame others who enlarge it. My purpose in the present volume is to
explain how the subject presented itself to Aristotle. He was the
first author that ever attempted to present Logic in a scientific
aspect; and it is hardly fair to try him by restrictions emanating
from critics much later. Yet, if he is to be tried upon this point, I
think the latitude in which he indulges preferable to the restricted
doctrine of Sir W. Hamilton.
[Footnote 48: See pp. 143-5 of the article, "Logic," in Sir William
Hamilton's Discussions on Philosophy--a very learned and instructive
article, even for those who differ from most of its conclusions.
Compare the opposite view, as advocated by M. Barthélemy St. Hilaire,
Logique d'Aristote, Préface, pp. **lxii.-lxviii.]
In the treatise now before us (De Interpretatione) Aristotle
announces his intention to explain the Proposition or Enunciative
Speech, the conjunction of a noun and a verb; as distinguished,
first, from its two constituents (noun and verb) separately taken;
next, from other modes of speech, also combining the two (precative,
interrogative, &c.). All speech (he says), the noun or verb
separately, as well as the proposition conjointly, is, in the first
instance, a sign of certain mental states common to the speaker with
his hearers; and, in the second instance, a sign of certain things or
facts, resembling (or correlating with) these mental states.[49] The
noun, pronounced separately, and the verb, pronounced separately, are
each signs of a certain thought in the speaker's mind, without either
truth or falsehood; the Proposition, or conjunction of the two, goes
farther and declares truth or falsehood. The words pronounced (he
says) follow the thoughts in the mind, expressing an opinion (_i.e._
belief or disbelief) entertained in the mind; the verbal affirmation
or negation gives utterance to a mental affirmation or negation--a
feeling of belief or disbelief--that something _is_, or that
something _is not_.[50] Thus, Aristotle intends to give a theory of
the Proposition, leaving other modes of speech to Rhetoric or
Poetry:[51] the Proposition he considers under two distinct aspects.
In its first or _subjective_ aspect, it declares the state of the
speaker's mind, as to belief or disbelief. In its second or
_objective_ aspect, it declares a truth or falsehood correlating with
such belief or disbelief, for the information of the hearer. Now the
Mode belonging to a proposition of this sort, in virtue of its
_form_, is to be _true_ or _false_. But there are also other
propositions--other varieties of speech enunciative--which differ
from the Simple or Assertory Proposition having the form _is_ or _is
not_, and which have distinct modes belonging to them, besides that
of being true or false. Thus we have the Necessary Proposition,
declaring that a thing _is_ so _by necessity_, that it _must be_ so,
or _cannot but be_ so; again, the Problematical Proposition,
enunciating that a thing _may or may not be so_. These two modes
attach to the _form_ of the proposition, and are quite distinct from
those which attach to its _matter_ as simply affirmed or denied; as
when, instead of saying, John is sick, we say, John is sick _of a
fever_, John is _dangerously_ sick, with a merely material
modification. Such adverbs, modifying the _matter_ affirmed or
denied, are numerous, and may be diversified almost without limit.
But they are not to be placed in the same category with the two just
mentioned, which modify the _form_ of the proposition, and correspond
to a state of mind distinct from simple belief or disbelief,
expressed by a simple affirmation or negation.[52] In the case of
each of the two, Aristotle has laid down rules (correct or incorrect)
for constructing the legitimate _Antiphasis_, and for determining
other propositions equipollent to, or following upon, the
propositions given; rules distinct from those applying to the simple
affirmation. When we say of anything, _It may be or may not be_, we
enunciate here only one proposition, not two; we declare a state of
mind which is neither belief nor disbelief, as in the case of the
Simple Proposition, but something wavering between the two; yet which
is nevertheless frequent, familiar to every one, and useful to be
made known by a special form of proposition adapted to it--the
Problematical. On the other hand, when we say, _It is by
necessity--must be--cannot but be_--we declare our belief, and
something more besides; we declare that the supposition of the
opposite of what we believe, would involve a contradiction--I would
contradict some definition or axiom to which we have already sworn
adherence. This again is a state of mind known, distinguishable, and
the same in all, subjectively; though as to the objective
correlate--what constitutes the Necessary, several different
opinions have been entertained.
[Footnote 49: Aristot. De Interpr. p. 16, a. 3-8: [Greek: e)/sti me\n
ou)=n ta\ e)n tê=| phônê=| tô=n e)n tê=| psuchê=| pathêma/tôn
su/mbola--ô(=n me/ntoi tau=ta sêmei=a _prô/tôs_, tau)ta\ pa=si
pathê/mata tê=s psuchê=s, kai\ ô(=n tau=ta o(moiô/mata, pra/gmata
ê)/dê tau)ta/.] Ibid. a. 13: [Greek: ta\ me\n ou)=n o)no/mata au)ta\
kai\ ta\ r(ê/mata e)/oike tô=| a)/neu sunthe/seôs kai\ diaire/seôs
noê/mati--ou)/te ga\r pseu=dos ou)/t' a)lêthe/s pô.] Ib. p. 17, a. 2:
[Greek: lo/gos a)pophantiko\s, e)n ô(=| to\ a)lêtheu/ein ê)\
pseu/desthai u(pa/rchei]. Compare p. 20, a. 34.]