76 Ibid. iii. p. 72, b. 20-30. καὶ οὐ μόνον ἐπιστήμην ἀλλὰ καὶ ἀρχὴν ἐπιστήμης εἶναι τινά φαμεν, ᾗ τοὺς ὅρους γνωρίζομεν.
Themistius, p. 14: ὧν δὴ ἄρχει πάλιν ὁ νοῦς ᾧ τοὺς ὅρους θηρεύομεν, ἐξ ὧν συγκεὶται τὰ ἀξιώματα.
The Paraphrase of Themistius (pp. 100-104) is clear and instructive, where he amplifies the last chapter, and explains Νοῦς as the generalizing or universalizing aptitude of the soul, growing up gradually out of the particulars furnished by Sense and Induction.
It is to be regretted that Aristotle should have contented himself with proclaiming this Inductive process as an ideal, culminating in the infallible Noûs; and that he should only have superficially noticed those conditions under which it must be conducted in reality, in order to avoid erroneous or uncertified results. This is a deficiency however which has remained unsupplied until the present century.77
77 Sir W. Hamilton, Lectures on Logic, Vol. III. Lect. xix. p. 380, says:— “In regard to simple syllogisms, it was an original dogma of the Platonic School, and an early dogma of the Peripatetic, that philosophy (science strictly so-called) was only conversant with, and was exclusively contained in, universals; and the doctrine of Aristotle, which taught that all our general knowledge is only an induction from an observation of particulars, was too easily forgotten or perverted by his followers. It thus obtained almost the force of an acknowledged principle, that everything to be known must be known under some general form or notion. Hence the exaggerated importance attributed to definition and deductions, it not being considered that we only take out of a general notion what we had previously placed therein, and that the amplification of our knowledge is not to be sought for from above but from below, — not from speculation about abstract generalities, but from the observation of concrete particulars. But however erroneous and irrational, the persuasion had its day and influence, and it perhaps determined, as one of its effects, the total neglect of one half, and that not the least important half, of the reasoning process. For while men thought only of looking upward to the more extensive notions, as the only objects and the only media of science, they took little heed of the more comprehensive notions, and absolutely contemned individuals, as objects which could neither be scientifically known in themselves nor supply the conditions of scientifically knowing aught besides. The Logic of Comprehension and of Induction was therefore neglected or ignored, — the Logic of Extension and Deduction exclusively cultivated, as alone affording the rules by which we might evolve higher notions into their subordinate concepts.”
(Hamilton, in this passage, considers the Logic of Induction to be the same as the Logic of Comprehension.)
CHAPTER IX.
TOPICA.
I.
In treating of the Analytica Posteriora I have already adverted, in the way of contrast, to the Topica; and, in now approaching the latter work, I must again bring the same contrast before the mind of the reader.
The treatise called Topica (including that which bears the separate title De Sophisticis Elenchis, but which is properly its Ninth or last Book, winding up with a brief but memorable recapitulation of the Analytica and Topica considered as one scheme) is of considerable length, longer than the Prior and Posterior Analytics taken together. It contains both a theory and precepts of Dialectic; also, an analysis of the process called by Aristotle Sophistical Refutation, with advice how to resist or neutralize it.
All through the works of Aristotle, there is nothing which he so directly and emphatically asserts to be his own original performance, as the design and execution of the Topica: i.e., the deduction of Dialectic and Sophistic from the general theory of Syllogism. He had to begin from the beginning, without any model to copy or any predecessor to build upon: and in every sort of work, he observes justly, the first or initial stages are the hardest.1 In regard to Rhetoric much had been done before him; there were not only masters who taught it, but writers who theorized well or ill, and laid down precepts about it; so that, in his treatise on that subject, he had only to enlarge and improve upon pre-existing suggestions. But in regard to Dialectic as he conceives it — in its contrast with Demonstration and Science on the one hand, and in its analogy or kinship with Rhetoric on the other — nothing whatever had been done. There were, indeed, teachers of contentious dialogue, as well as of Rhetoric;2 but these teachers could do nothing better than recommend to their students dialogues or orations ready made, to be learnt by heart. Such a mode of teaching (he says), though speedy, was altogether unsystematic. The student acquired no knowledge of the art, being furnished only with specimens of art-results. It was as if a master, professing to communicate the art of making the feet comfortable, taught nothing about leather-cutting or shoe-making, but furnished his pupils with different varieties of ready-made shoes; thus supplying what they wanted for the protection of the feet, but not imparting to them any power of providing such protection for themselves.3 “In regard to the process of syllogizing (says Aristotle, including both Analytic and Dialectic) I found positively nothing said before me: I had to work it out for myself by long and laborious research.”4
1 Aristot. Sophist. Elench. xxxiv. p. 183, b. 22: μέγιστον γὰρ ἴσως ἀρχὴ παντός, ὥσπερ λέγεται· διὸ καὶ χαλεπώτατον. ὅσῳ γὰρ κράτιστον τῇ δυνάμει, τοσούτῳ μικρότατον ὂν τῷ μεγέθει χαλεπώτατόν ἐστιν ὀφθῆναι.
2 Sophist. Elench. xxxiv. p. 183, b. 34: ταύτης δὲ τῆς πραγματείας οὐ τὸ μὲν ἦν τὸ δ’ οὐκ ἦν προεξειργασμένον, ἀλλ’ οὐδὲν παντελῶς ὑπῆρχεν. καὶ γὰρ τῶν περὶ τοὺς ἐριστικοὺς λόγους μισθαρνούντων ὁμοία τις ἦν ἡ παίδευσις τῇ Γοργίου πραγματείᾳ· λόγους γὰρ οἱ μὲν ῥητορικοὺς οἱ δὲ ἐρωτητίκους ἐδίδοσαν ἐκμανθάνειν, εἰς οὓς πλειστάκις ἐμπίπτειν ὠήθησαν ἑκάτεροι τοὺς ἀλλήλων λόγους.
3 Ibid. xxxiv. p. 184, a. 2.
4 Ibid. a. 7: καὶ περὶ μὲν τῶν ῥητορικῶν πολλὰ καὶ παλαιὰ τὰ λεγόμενα, περὶ δὲ τοῦ συλλογίζεσθαι παντελῶς οὐδὲν εἴχομεν πρότερον ἄλλο λέγειν, ἀλλ’ ἢ τριβῇ ζητοῦντες πολὺν χρόνον ἐπονοῦμεν.
This is one of the few passages, throughout the philosopher’s varied and multitudinous works, in which he alludes to his own speciality of method. It is all the more interesting on that account. If we turn back to Sokrates and Plato, we shall understand better what the innovation operated by Aristotle was; what the position of Dialectic had been before his time, and what it became afterwards.
In the minds of Sokrates and Plato, the great antithesis was between Dialectic and Rhetoric — interchange of short question and answer before a select audience, as contrasted with long continuous speech addressed to a miscellaneous crowd with known established sentiments and opinions, in the view of persuading them on some given interesting point requiring decision. In such Dialectic Sokrates was a consummate master; passing most of his long life in the market-place and palæstra, and courting disputation with every one. He made formal profession of ignorance, disclaimed all power of teaching, wrote nothing at all, and applied himself almost exclusively to the cross-examining Elenchus by which he exposed and humiliated the ablest men not less than the vulgar. Plato, along with the other companions of Sokrates, imbibed the Dialectic of his master, and gave perpetuity to it in those inimitable dialogues which are still preserved to us from his pen. He composed nothing but dialogues; thus giving expression to his own thoughts only under borrowed names, and introducing that of Sokrates very generally as chief spokesman. But Plato, though in some dialogues he puts into the mouth of his spokesman the genuine Sokratic disclaimer of all power and all purpose of teaching, yet does not do this in all. He sometimes assumes the didactic function; though he still adheres to the form of dialogue, even when it has become inconvenient and unsuitable. In the Platonic Republic Sokrates is made to alternate his own peculiar vein of cross-examination with a vein of dogmatic exposition not his own; but both one and the other in the same style of short question and answer. In the Leges becomes still more manifest the inconvenience of combining the substance of dogmatic exposition with the form of dialogue: the same remark may also be made about the Sophistes and Politicus; in which two dialogues, moreover, the didactic process is exhibited purely and exclusively as a logical partition, systematically conducted, of a genus into its component species. Long-continued speech, always depreciated by Plato in its rhetorical manifestations, is foreign to his genius even for purposes of philosophy: the very lecture on cosmogony which he assigns to Timæus, and the mythical narrative (unfinished) delivered by Kritias, are brought into something like the form of dialogue by a prefatory colloquy specially adapted for that end.
It thus appears that, while in Sokrates the dialectic process is exhibited in its maximum of perfection, but disconnected altogether from the didactic, which is left unnoticed, — in Plato the didactic process is recognized and postulated, but is nevertheless confounded with or absorbed into the dialectic, and admitted only as one particular, ulterior, phase and manifestation of it. At the same time, while both Sokrates and Plato bring out forcibly the side of antithesis between Rhetoric and Dialectic, they omit entirely to notice the side of analogy or parallelism between them. On both these points Aristotle has corrected the confusion, and improved upon the discrimination, of his two predecessors. He has pointedly distinguished the dialectic process from the didactic; and he has gone a step farther, furnishing a separate theory and precepts both for the one and for the other. Again, he has indicated the important feature of analogy between Dialectic and Rhetoric, in which same feature both of them contrast with Didactic — the point not seized either by Sokrates or by Plato.
Plato, in his Sokratic dialogues or dialogues of Search, has given admirable illustrative specimens of that which Sokrates understood and practised orally as Dialectic. Aristotle, in his Topica, has in his usual vein of philosophy theorized on this practice as an art. He had himself composed dialogues, which seem as far as we can judge from indirect and fragmentary evidence, to have been Ciceronian or rhetorical colloquies — a long pleading pro followed by a long pleading con, rather than examples of Sokratic brachylogy and cross-examination. But his theory given in the Topica applies to genuine Sokratic fencing, not to the Ciceronian alternation of set speeches. He disallows the conception of Plato, that Dialectic is a process including not merely dispute but all full and efficacious employment of general terms and ideas for purposes of teaching: he treats this latter as a province by itself, under the head of Analytic: and devotes the Topica to the explanation of argumentative debate, pure and simple. He takes his departure from the Syllogism, as the type of deductive reasoning generally; the conditions under which syllogistic reasoning is valid and legitimate, having been already explained in his treatise called Analytica Priora. So obtained, and regulated by those conditions, the Syllogism may be applied to one or other of two distinct and independent purposes:— (1) To Demonstration or Scientific Teaching, which we have had before us in the last two chapters, commenting on the Analytica Posteriora; (2) To Dialectic, or Argumentative Debate, which we are now about to enter on in the Topica.
The Dialectic Syllogism, explained in the Topica, has some points in common with the Demonstrative Syllogism, treated in the Analytica Posteriora. In both, the formal conditions are the same, and the conclusions will certainly be true, if the premisses are true; in both, the axioms of deductive reasoning are assumed, namely, the maxims of Contradiction and Excluded Middle. But, in regard to the subject-matter, the differences between them are important. The Demonstrative Syllogism applies only to a small number of select sciences, each having special principia of its own, or primary, undemonstrable truths, obtained in the first instance by induction from particulars. The premisses being thus incontrovertibly certain, the conclusions deduced are not less certain; there is no necessary place for conflicting arguments or counter-syllogisms, although in particular cases paralogisms may be committed, and erroneous propositions or majors for syllogism may be assumed. On the contrary, the Dialectic Syllogism applies to all matters without exception; the premisses on which it proceeds are neither obtained by induction, nor incontrovertibly certain, but are borrowed from some one among the varieties of accredited or authoritative opinion. They may be opinions held by the multitude of any particular country, or by an intelligent majority, or by a particular school of philosophers or wise individuals, or from transmission as a current proverb or dictum of some ancient poet or seer. From any one of these sources the dialectician may borrow premisses for syllogizing. But it often happens that the premisses which they supply are disparate, or in direct contradiction to each other; and none of them is entitled to be considered as final or peremptory against the rest. Accordingly, it is an essential feature of Dialectic as well as of Rhetoric that they furnish means of establishing conclusions contrary or contradictory, by syllogisms equally legitimate.5 The dialectic procedure is from its beginning intrinsically contentious, implying a debate between two persons, one of whom sets up a thesis to defend, while the other impugns it by interrogation: the assailant has gained his point, if he can reduce the defendant to the necessity of contradicting himself; while the defendant on his side has to avoid giving any responses which may drive him to the necessity of such contradiction.
5 Aristot. Rhetoric. I. i. p. 1355, a. 29: ἔτι δὲ τἀναντία δεῖ δύνασθαι πείθειν, καθάπερ καὶ ἐν τοῖς συλλογισμοῖς, οὐχ ὅπως ἀμφότερα πράττωμεν, (οὐ γὰρ δεῖ τὰ φαῦλα πείθειν), ἀλλ’ ἵνα μήτε λανθάνῃ πῶς ἔχει, καὶ ὅπως ἄλλου χρωμένου τοῖς λόγοις μὴ δικαίως αὐτοὶ λύειν ἔχωμεν. τῶν μὲν οὖν ἄλλων τεχνῶν οὐδεμία τἀναντία συλλογίζεται· ἡ δὲ διαλεκτικὴ καὶ ἡ ῥητορικὴ μόναι τοῦτο ποιοῦσιν· ὁμοίως γάρ εἰσιν ἀμφότεραι τῶν ἐναντίων.
Aristotle takes great pains to enforce the separation both of Dialectic and Rhetoric from Science or Instruction with its purpose of teaching or learning. He disapproves of those (seemingly intending Plato) who seek to confound the two. Dialectic and Rhetoric (he says) have for their province words and discourse, not facts or things: they are not scientific or didactic processes, but powers or accomplishments of discourse; and whoever tries to convert them into means of teaching or learning particular subjects, abolishes their characteristic feature and restricts their universality of application.6 Both of them deal not with scientific facts, but with the sum total of accredited opinions, though each for its own purpose: both of them lay hold of any one among the incoherent aggregate of accepted generalities, suitable for the occasion; the Dialectician trying to force his opponent into an inconsistency, the Rhetor trying to persuade his auditors into a favourable decision. Neither the one nor the other goes deeper than opinion for his premisses, nor concerns himself about establishing by induction primary or special principia, such as may serve for a basis of demonstration.
6 Ibid. iv. 2, p. 1359, b. 12: ὅσῳ δ’ ἄν τις ἢ τὴν διαλεκτικὴν ἢ ταύτην (τὴν ῥητορικὴν) μὴ καθάπερ ἂν δυνάμεις, ἀλλ’ ἐπιστήμας, πειρᾶται κατασκευάζειν, λήσεται τὴν φύσιν αὐτῶν ἀφανίσας, τῷ μεταβαίνειν ἐπισκευάζων εἰς ἐπιστήμας ὑποκειμένων τινῶν πραγμάτων, ἀλλὰ μὴ μόνον λόγων.
In every society there are various floating opinions and beliefs, each carrying with it a certain measure of authority, often inconsistent with each other, not the same in different societies, nor always the same even in the same society. Each youthful citizen, as he grows to manhood, imbibes these opinions and beliefs insensibly and without special or professional teaching.7 The stock of opinions thus transmitted would not be identical even at Athens and Sparta: the difference would be still greater, if we compared Athens with Rome, Alexandria, or Jerusalem. Such opinions all carry with them more or less of authority, and it is from them that the reasonings of common life, among unscientific men, are supplied. The practice of dialectical discussion, prevalent in Athens during and before the time of Aristotle, was only a more elaborate, improved, and ingenious exhibition of this common talk; proceeding on the same premisses, but bringing them together from a greater variety of sources, handling them more cleverly, and having for its purpose to convict an opponent of inconsistency. The dialecticians dwelt exclusively in the region of these received opinions; and the purpose of their debates was to prove inconsistency, or to repel the proof of inconsistency, between one opinion and another.
7 For an acute and interesting description of this unsystematic transmission of opinions, see, in the Protagoras of Plato, the speech put into the mouth of Protagoras, pp. 323-325. See also ‘Plato and the Other Companions of Sokrates,’ Vol. II. ch. xxi. p. 45, seq.
This dialectic debate, which Aristotle found current at Athens, he tries in the Topica to define and reduce to system. The dialectician must employ Syllogism; and we are first taught to distinguish the Syllogism that he employs from others. The Dialectic syllogism is discriminated on one side from the Demonstrative, on the other from the Eristic (or litigious); also from the scientific Paralogism or Pseudographeme. This discrimination is founded on the nature of the evidence belonging to the premisses. The Demonstrative syllogism (which we have already gone through in the Analytica Posteriora) has premisses noway dependent upon opinion: it deduces conclusions from true first principles, obtained by Induction in each science, and different in each different science. The Dialectic syllogism does not aspire to any such evidence, but borrows its premisses from Opinion of some sort; accredited either by numbers, or by wise individuals, or by some other authoritative holding. As this evidence is very inferior to that of the demonstrative syllogism, so again it is superior to that of the third variety — the Eristic syllogism. In this third variety,8 the premisses do not rest upon any real opinion, but only on a fallacious appearance or simulation of opinion; insomuch that they are at once detected as false, by any person even of moderate understanding; whereas (according to Aristotle) no real opinion ever carries with it such a merely superficial semblance, or is ever so obviously and palpably false. A syllogism is called Eristic also when it is faulty in form, though its premisses may be borrowed from real opinion, or when it is both faulty in form and false in the matter of the premisses. Still a fourth variety of syllogism is the scientific Paralogism: where the premisses are not borrowed from any opinion, real or simulated, but belong properly to the particular science in which they are employed, yet nevertheless are false or erroneous.9
8 Topic. I. p. 100, b. 23: ἐριστικὸς δ’ ἔστι συλλογισμὸς ὁ ἐκ φαινομένων ἐνδόξων, μὴ ὄντων δέ, καὶ ὁ ἐξ ἐνδόξων ἢ φαινομένων ἐνδόξων φαινόμενος. οὐ γὰρ πᾶν τὸ φαινόμενον ἔνδοξον καὶ ἔστιν ἔνδοξον. οὐθὲν γὰρ τῶν λεγομένων ἐνδόξων ἐπιπόλαιον ἔχει παντελῶς τὴν φαντασίαν, καθάπερ περὶ τὰς τῶν ἐριστικῶν λόγων ἀρχὰς συμβέβηκεν ἔχειν· παραχρῆμα γὰρ καὶ ὡς ἐπὶ τὸ πολὺ τοῖς καὶ μικρὰ συνορᾶν δυναμένοις κατάδηλος ἐν αὐτοῖς ἡ τοῦ ψεύδους ἐστὶ φύσις.
9 Ibid. i. p. 101, a. 5-17.
Upon the classification of syllogisms here set forth by Aristotle, we may remark that the distinction between the Demonstrative and the Dialectic is true and important; but that between the Dialectic and the Eristic is faint and unimportant; the class called Eristic syllogisms being apparently introduced merely to create a difference, real or supposed, between the Dialectician and the Sophist, and thus to serve as a prelude to the last book of this treatise, entitled Sophistici Elenchi. The class-title Eristic (or litigious) is founded upon a supposition of dishonest intentions on the part of the disputant; but it is unphilosophical to make this the foundation of a class, and to rank the same syllogism in the class, or out of it, according as the intentions of the disputant who employs it are honest or dishonest. Besides, a portion of Aristotle’s definition tells us that the Eristic syllogism is one of which the premisses can impose upon no one; being such that a very ordinary man can at once detect their falsity. The dishonest disputant, surely, would argue to little purpose, if he intentionally employed such premisses as these. Lastly, according to another portion of Aristotle’s definition, every syllogism faulty in form, or yielding no legitimate conclusion at all, will fall under the class Eristic, and this he himself in another place explicitly states;10 which would imply that the bad syllogism must always emanate from litigious or dishonest intentions. But in defining the Pseudographeme, immediately afterwards, Aristotle does not imply that the false scientific premiss affords presumption of litigious disposition on the part of those who advance it; nor does there seem any greater propriety in throwing all bad dialectic syllogisms under the general head of Eristic.
10 Topic. VIII. xii. p. 162, b. 4.
The dialectician, then, will carry on debate only by means of premisses sustained by real opinion; which not only always carry some authority, but are assumed as being never obviously fallacious; though often inconsistent with each other, and admitting of argumentation pro and con. These are what Aristotle calls Endoxa; opposed to Adoxa, or propositions which are discountenanced, or at least not countenanced, by opinion, and to Paradoxa (a peculiar variety of Adoxa),11 or propositions which, though having ingenious arguments in their favour, yet are adverse to some proclaimed and wide-spread opinions, and thus have the predominant authority of opinion against them.
11 Ibid. I. xi. p. 104, b. 24: περὶ ὧν λόγον ἔχομεν ἐναντίον ταῖς δόξαις.
Of these three words, Paradox is the only one that has obtained a footing in modern languages, thanks to Cicero and the Latin authors. If the word Endox had obtained the like footing, we should be able to keep more closely to the thought and views of Aristotle. As it is, we are obliged to translate the Greek Endoxon as Probable, and Adoxon as Improbable:12 which, though not incorrect, is neither suitable nor exactly coincident. Probable corresponds more nearly to what Aristotle (both in this treatise and in the Analytica) announces sometimes as τὸ ὡς ἐπὶ τὸ πολύ — that which happens in most cases but not in all, as distinguished from the universal and necessary on one side, and from the purely casual on the other;13 sometimes, also, as τὸ εἰκός or τὸ σημεῖον. Now this is a different idea from (though it has a point of analogy with) the Endoxon: which is not necessarily true even in part, but may be wholly untrue; which always has some considerations against it, though there may be more in its favour; and which, lastly, may be different, or even opposite, in different ages and different states of society. When Josephus distinguished himself as a disputant in the schools of Jerusalem on points of law and custom,14 his arguments must have been chiefly borrowed from the Endoxa or prevalent opinions of the time and place; but these must have differed widely from the Endoxa found and argued upon by the contemporaries of Aristotle at Athens. The Endoxon may indeed be rightly called probable, because, whenever a proposition is fortified by a certain body of opinion, Aristotle admits a certain presumption (greater or less) that it is true. But such probability is not essential to the Endoxon: it is only an accident or accompaniment (to use the Aristotelian phrase), and by no means an universal accompaniment. The essential feature of the Endoxon is, that it has acquired a certain amount of recognition among the mass of opinions and beliefs floating and carrying authority at the actual time and place. The English word whereby it is translated ought to express this idea, and nothing more; just as the correlative word Paradox does express its implication, approached from the other side. Unfortunately, in the absence of Endox, we have no good word for the purpose.
12 Aristotle gives a double meaning of ἄδοξον (Topic. VIII. ix. ix. 160, b. 17):— 1. That which involves absurd or strange consequences (ἄτοπα). 2. That which affords presumption of a bad disposition, such as others will disapprove — οἷον ὅτι ἡδονὴ τἀγαθὸν καὶ τὸ ἀδικεῖν βέλτιον τοῦ ἀδικεῖσθαι.
13 Topic. II. vi. p. 112, b. 1: ἐπεὶ δὲ τῶν πραγμάτων τὰ μὲν ἐξ ἀνάγκης ἐστί, τὰ δ’ ὡς ἐπὶ τὸ πολύ, τὰ δ’ ὁπότερ’ ἔτυχεν, &c. Compare also Analyt. Post. I. xxx., et alib.
14 See Josephus, De Vitâ Suâ, c. ii.
It is within this wide field of floating opinions that dialectical debate and rhetorical pleading are carried on. Dialectic supposes a questioner or assailant, and a respondent or defendant. The respondent selects and proclaims a problem or thesis, which he undertakes to maintain: the assailant puts to him successive questions, with the view of obtaining concessions which may serve as premisses for a counter-syllogism, of which the conclusion is contradictory or contrary to the thesis itself, or to some other antecedent premiss which the respondent has already conceded. It is the business of the respondent to avoid making any answers which may serve as premisses for such a counter-syllogism. If he succeeds in this, so as not to become implicated in any contradiction with himself, he has baffled his assailant, and gained the victory. There are, however, certain rules and conditions, binding on both parties, under which the debate must be carried on. It is the purpose of the Topica to indicate these rules; and, in accordance therewith, to advise both parties as to the effective conduct of their respective cases—as to the best thrusts and the best mode of parrying. The assailant is supplied with a classified catalogue of materials for questions, and with indications of the weak points which he is to look out for in any new subject which may turn up for debate. He is farther instructed how to shape, marshal, and disguise his questions, in such a way that the respondent may least be able to foresee their ultimate bearing. The respondent, on his side, is told what he ought to look forward to and guard against. Such is the scope of the present treatise; the entire process being considered in the large and comprehensive spirit customary with Aristotle, and distributed according to the Aristotelian terminology and classification.
It is plain that neither the direct purpose of the debaters, nor the usual result of the debate, is to prove truth or to disprove falsehood. Such may indeed be the result occasionally; but the only certain result is, that an inconsistency is exposed in the respondent’s manner of defending his thesis, or that the assailant fails in his purpose of showing up such inconsistency. Whichever way the debate may turn, no certain inference can be drawn as to the thesis itself: not merely as to whether it is true or false, but even as to whether it consists or does not consist with other branches of received opinions. Such being the case, what is the use or value of dialectic debate, or of a methodized procedure for conducting it? Aristotle answers this question, telling us that it is useful for three purposes.15 First, the debate is a valuable and stimulating mental exercise; and, if a methodized procedure be laid down, both parties will be able to conduct it more easily as well as more efficaciously. Secondly, it is useful for our intercourse with the multitude;16 for the procedure directs us to note and remember the opinions of the multitude, and such knowledge will facilitate our intercourse with them: we shall converse with them out of their own opinions, which we may thus be able beneficially to modify. Thirdly, dialectic debate has an useful though indirect bearing even upon the processes of science and philosophy, and upon the truths thereby acquired.17 For it accustoms us to study the difficulties on both sides of every question, and thus assists us in detecting and discriminating truth and falsehood. Moreover, apart from this mode of usefulness, it opens a new road to the scrutiny of the first principia of each separate science. These principia can never be scrutinized through the truths of the science itself, which presuppose them and are deduced from them. To investigate and verify them, is the appropriate task of First Philosophy. But Dialectic also, carrying investigation as it does everywhere, and familiarized with the received opinions on both sides of every subject, suggests many points of importance in regard to these principia.
15 Topic. I. ii. p. 101, a. 26: ἔστι δὴ πρὸς τρία, πρὸς γυμνασίαν, πρὸς τὰς ἐντεύξεις, πρὸς τὰς κατὰ φιλοσοφίαν ἐπιστήμας.
16 Ibid. a. 30: πρὸς δὲ τὰς ἐντεύξεις, διότι τὰς τῶν πολλῶν κατηριθμημένοι δόξας οὐκ ἐκ τῶν ἀλλοτρίων ἀλλ’ ἐκ τῶν οἰκείων δογμάτων ὁμιλήσομεν πρὸς αὐτούς, μεταβιβάζοντες ὅ τι ἂν μὴ καλῶς φαίνωνται λέγειν ἡμῖν.
17 Ibid. a. 34: πρὸς δὲ τὰς κατὰ φιλοσοφίαν ἐπιστήμας, &c.
The three heads just enumerated illustrate the discriminating care of Aristotle. The point of the first head is brought out often in the Platonic Dialogues of Search: the stimulus brought to bear in awakening dormant intellectual power, and in dissipating that false persuasion of knowledge which is the general infirmity of mankind, is frequently declared by Plato to be the most difficult, but the indispensable, operation of the teacher upon his pupil. Under the third head, Aristotle puts this point more justly than Plato, not as a portion of teaching, nor as superseding direct teaching, but as a preliminary thereunto; and it is a habit of his own to prefix this antecedent survey of doubts and difficulties on both sides, as a means of sharpening our insight into the dogmatic exposition which immediately follows.
Under the second head, we find exhibited another characteristic feature of Aristotle’s mind — the value which he sets upon a copious acquaintance with received opinions, whether correct or erroneous. The philosophers of his day no longer talked publicly in the market-place and with every one indiscriminately, as Sokrates had done: scientific study, and the habit of written compositions naturally conducted them into a life apart, among select companions. Aristotle here indicates that such estrangement from the multitude lessened their means of acting beneficially on the multitude, and in the way of counteraction he prescribes dialectical exercise. His own large and many-sided observation, extending to the most vulgar phenomena, is visible throughout his works, and we know that he drew up a collection of current proverbs.18
18 Diog. Laert. v. 26. Kephisodorus, the disciple of Isokrates, in defending his master, depreciated this Aristotelian collection; see in Athenæus II. lvi., comparing Schweighäuser’s Animadversiones I. p. 406.
Again, what we read under the third head shows that, while Aristotle everywhere declares Demonstration and teaching to be a process apart from Dialectic, he at the same time recognizes the legitimate function of the latter, for testing and verifying the principia of Demonstration:19 which principia cannot be reached by Demonstration itself, since every demonstration presupposes them. He does not mean that these principia can be proved by Dialectic, for Dialectic does not prove any thing; but it is necessary as a test or scrutinizing process to assure us that all the objections capable of being offered against them can be met by sufficient replies. In respect of universal competence and applicability, Dialectic is the counterpart, or rather the tentative companion and adjunct, of what Aristotle calls First Philosophy or Ontology; to which last he assigns the cognizance of principia, as we shall see when we treat of the Metaphysica.20 Dialectic (he repeats more than once) is not a definite science or body of doctrine, but, like rhetoric or medicine, a practical art or ability of dealing with the ever varying situations of the dialogue; of imagining and enunciating the question proper for attack, or the answer proper for defence, as the case may be. As in the other arts, its resources are not unlimited. Nor can the dialectician, any more than the rhetor or the physician, always guarantee success. Each of them has an end to be accomplished; and if he employs for its accomplishment the best means that the situation permits, he must be considered a master of his own art and procedure.21 To detect truth, and to detect what is like truth, belong (in Aristotle’s judgment) to the same mental capacity. Mankind have a natural tendency towards truth, and the common opinions therefore are, in most cases, coincident with truth. Accordingly, the man who divines well in regard to verisimilitude, will usually divine well in regard to truth.22