Aristotle
of speaking, when we have only signs or probabilities to guide us,
and not certain proofs. The feeling of doubt is, as a psychological
phenomenon, essentially distinct from the feeling of belief which, in
its objective aspect, correlates with certainty or matter of fact; as
well as from the feeling of disbelief, the correlate of which can
only be described negatively. Every man knows these feelings by his
own mental experience. But in describing the feeling of doubt, as to
its matter or in its objective aspect, we must take care to use
phrases which declare plainly both sides of its disjunctive or
alternative character. The Possible is, _That which either may be or
may not be_. As _That which may be_, it stands opposed to the
Impossible; as _That which may not be_, it stands opposed to the
Necessary. It thus carries with it negation both of impossibility and
of necessity; but, in common parlance, the first half of this meaning
stands out prominently, and is mistaken for the whole. Aristotle, as
we saw previously, speaks equivocally on this point, recognizing a
double signification of the term: he sometimes uses it in the sense
opposed only to impossible, maintaining that what is necessary must
also be possible; sometimes in the truer sense, opposed both to
necessity and to impossibility.[82]
[Footnote 82: Aristot. De Interpret. xiii. p. 22. Analyt. Prior. I.
xiii. p. 32, a. 21, 29, 36, xiv. p. 33, b. 22; xix. p. 38, a. 35.]
The Possible or Problematical, however, in this latter complete
sense--_What may or may not be_--exhibits various modifications or
gradations. 1. The chances on either side may be conceived as
perfectly equal, so that there is no probability, and we have no more
reason for expecting one side of the alternative than the other; the
sequence or conjunction is indeterminate. Aristotle construes this
indeterminateness in many cases (not as _subjective_, or as depending
upon our want of complete knowledge and calculating power, but) as
_objective_, insuperable, and inherent in many phenomenal agencies;
characterizing it, under the names of Spontaneity and Chance, as the
essentially unpredictable. 2. The chances on both sides may be
conceived as unequal and the ratio between them as varying
infinitely: the usual and ordinary tendency of phenomena--what
Aristotle calls Nature--prevails in the majority of cases, but not in
all; being liable to occasional counteraction from Chance and other
forces. Thus, between Necessity and perfect constancy at one extreme
(such as the rotation of the sidereal sphere), and Chance at the
other, there may be every shade of gradation; from natural agency
next below the constant, down to the lowest degree of
probability.[83]
[Footnote 83: Analyt. Prior. I. xiii. p. 32, b. 5-19. [Greek: to\ d'
a)o/riston tô=| mêde\n ma=llon ou(/tôs ê)\ e)kei/nôs]. Compare
Metaphys. K. p. 1064, b. 32.]
Now, within the range of these limits lie what Aristotle describes as
Signs and Probabilities; in fact, all the marks which we shall
presently come to as distinguishing the _dialectical_ syllogism from
the _demonstrative_. But here is involved rather the matter of the
Syllogism than its form. The form indeed is so far implicated, that
(as Aristotle justly remarks at the end of the Analytica Priora[84]),
the First figure is the only one that will prove both conjunctions
and disjunctions, as well constant as occasional; the Third figure
proves only occasional conjunctions and occasional disjunctions, not
constant; the Second figure will prove no conjunctions at all, but
only disjunctions, constant as well as occasional. Here a difference
of form is properly pointed out as coupled with and founded on a
difference of matter. But the special rules given by Aristotle, early
in the present treatise, for the conversion of Modal Propositions,
and the distinctions that he draws as to the modal character of the
conclusion according as one or other of the premisses belongs to one
or other of the different modes,--are both prolix and of little
practical value.[85]
[Footnote 84: Analyt. Prior. II. xxvii. p. 70, a. 2-38. Compare what
is said here about [Greek: ei)ko/s, sêmei=on, tekmê/rion], with the
first chapter of the Topica, and the dialectic syllogism as there
described: [Greek: o( e)x e)ndo/xôn sullogizo/menos].]
[Footnote 85: Ibid. I. viii.-xxii. p. 29, b. 29-p. 40, b. 16.]
What he calls the Necessary might indeed, from the point of view now
reached, cease to be recognized as a separate mode at all. The
Certain and the Problematical are real modes of the Proposition;
objective correlates to the subjective phases called Belief and
Doubt. But no proposition can be more than certain: the word
_necessary_, in strictness, implies only a peculiarity of the
evidence on which our belief is grounded. Granting certain given
premisses to be true, a given conclusion must be true also, if we
would avoid inconsistency and contradiction.
CHAPTER VII.
ANALYTICA POSTERIORA I.
In the two books of Analytica Priora, Aristotle has carried us
through the full doctrine of the functions and varieties of the
Syllogism; with an intimation that it might be applied to two
purposes--Demonstration and Dialectic. We are now introduced to these
two distinct applications of the Syllogism: first, in the Analytica
Posteriora, to Demonstration; next, in the Topica, to Dialectic. We
are indeed distinctly told that, as far as the forms and rules of
Syllogism go, these are alike applicable to both;[1] but the
difference of matter and purpose in the two cases is so considerable
as to require a distinct theory and precepts for the one and for the
other.
[Footnote 1: Analyt. Prior. I. xxx. p. 46, a. 4-10; Analyt. Post. I.
ii. p. 71, a. 23.]
The contrast between Dialectic (along with Rhetoric) on the one hand
and Science on the other is one deeply present to the mind of
Aristotle. He seems to have proceeded upon the same fundamental
antithesis as that which appears in the Platonic dialogues; but to
have modified it both in meaning and in terminology, dismissing at
the same time various hypotheses with which Plato had connected it.
The antithesis that both thinkers have in view is Opinion or Common
Sense _versus_ Science or Special Teaching and Learning; those
aptitudes, acquirements, sentiments, antipathies, &c., which a man
imbibes and appropriates insensibly, partly by his own doing and
suffering, partly by living amidst the drill and example of a given
society--as distinguished from those accomplishments which he derives
from a teacher already known to possess them, and in which both the
time of his apprenticeship and the steps of his progress are alike
assignable.
Common Sense is the region of Opinion, in which there is diversity of
authorities and contradiction of arguments without any settled truth;
all affirmations being particular and relative, true at one time and
place, false at another. Science, on the contrary, deals with
imperishable Forms and universal truths, which Plato regards, in
their subjective aspect, as the innate, though buried, furniture of
the soul, inherited from an external pre-existence, and revived in it
out of the misleading data of sense by a process first of the
cross-examining _Elenchus_, next of scientific Demonstration. Plato
depreciates altogether the untaught, unexamined, stock of
acquirements which passes under the name of Common Sense, as a mere
worthless semblance of knowledge without reality; as requiring to be
broken up by the scrutinizing _Elenchus_, in order to impress a
painful but healthy consciousness of ignorance, and to prepare the
mind for that process of teaching whereby alone Science or Cognition
can be imparted.[2] He admits that Opinion may be right as well as
wrong. Yet even when right, it is essentially different from Science,
and is essentially transitory; a safe guide to action while it lasts,
but not to be trusted for stability or permanence.[3] By Plato,
Rhetoric is treated as belonging to the province of Opinion,
Dialectic to that of Science. The rhetor addresses multitudes in
continuous speech, appeals to received common places, and persuades:
the dialectician, conversing only with one or a few, receives and
imparts the stimulus of short question and answer; thus awakening the
dormant capacities of the soul to the reminiscence of those universal
Forms or Ideas which are the only true Knowable.
[Footnote 2: Plato, Sophistes, pp. 228-229; Symposion, pp. 203-204;
Theætetus, pp. 148, 149, 150. Compare also 'Plato and the Other
Companions of Sokrates,' Vol. I. chs. vi.-vii. pp. 245-288; II. ch.
xxvi. p. 376, seq.]
[Footnote 3: Plato, Republic, v. pp. 477-478; Menon, pp. 97-98.]
Like Plato, Aristotle distinguishes the region of Common Sense or
Opinion from that of Science, and regards Universals as the objects
of Science. But his Universals are very different from those of
Plato: they are not self-existent realities, known by the mind from a
long period of pre-existence, and called up by reminiscence out of
the chaos of sensible impressions. To operate such revival is the
great function that Plato assigns to Dialectic. But in the philosophy
of Aristotle Dialectic is something very different. It is placed
alongside of Rhetoric in the region of Opinion. Both the rhetor and
the dialectician deal with all subjects, recognizing no limit; they
attack or defend any or all conclusions, employing the process of
ratiocination which Aristotle has treated under the name of
Syllogism; they take up as premisses any one of the various opinions
in circulation, for which some plausible authority may be cited; they
follow out the consequences of one opinion in its bearing upon
others, favourable or unfavourable, and thus become well furnished
with arguments for and against all. The ultimate foundation here
supposed is some sort of recognized presumption or authoritative
sanction[4]--law, custom, or creed, established among this or that
portion of mankind, some maxim enunciated by an eminent poet, some
doctrine of the Pythagoreans or other philosophers, current proverb,
answer from the Delphian oracle, &c. Any one of these may serve as a
dialectical authority. But these authorities, far from being
harmonious with each other, are recognized as independent,
discordant, and often contradictory. Though not all of equal
value,[5] each is sufficient to warrant the setting up of a thesis
for debate. In Dialectic, one of the disputants undertakes to do
this, and to answer all questions that may be put to him respecting
the thesis, without implicating himself in inconsistencies or
contradiction. The questioner or assailant, on the other hand, shapes
his questions with a view to refute the thesis, by eliciting answers
which may furnish him with premisses for some syllogism in
contradiction thereof. But he is tied down by the laws of debate to
syllogize only from such premisses as the respondent has expressly
granted; and to put questions in such manner that the respondent is
required only to give or withhold assent, according as he thinks
right.
[Footnote 4: Aristot. Topica, I. x. p. 104, a. 8, xi. p. 104, b. 19.
Compare Metaphysica, A. p. 995, a. 1-10.]
[Footnote 5: Analyt. Post. I. xix. p. 81, b. 18: [Greek: kata\ me\n
ou)=n do/xan sullogizome/nois kai\ mo/non dialektikô=s dê=lon o(/ti
tou=to mo/non skepte/on, ei) e)x ô(=n e)nde/chetai e)ndoxota/tôn
gi/netai o( sullogismo/s, ô(/st' ei) kai\ e)/sti ti tê=| a)lêthei/a|
tô=n AB me/son, dokei= de\ mê/, o( dia\ tou/tou sullogizo/menos
sullelo/gistai dialektikô=s, pro\s d' a)lê/theian e)k tô=n
u(parcho/ntôn dei= skopei=n.] Compare Topica, VIII. xii. p. 162, b.
27.]
We shall see more fully how Aristotle deals with Dialectic, when we