Some critics, assuming confidently that Plato must have produced a full breadth of positive philosophy to countervail his own negative fertility, yet not finding enough of it in the written dialogues look for it elsewhere. Tennemann thinks, and his opinion is partly shared by Boeckh and K. F. Hermann, that the direct, affirmative, and highest principles of Plato’s philosophy were enunciated only in his lectures: that the core, the central points, the great principles of his system (der Kern) were revealed thus orally to a few select students in plain and broad terms, while the dialogues were intentionally written so as to convey only indirect hints, illustrations, applications of these great principles, together with refutation of various errors opposed to them: that Plato did not think it safe or prudent to make any full, direct, or systematic revelation to the general public.[101] I have already said that I think this opinion untenable. Among the few points which we know respecting the oral lectures, one is, that they were delivered not to a select and prepared few, but to a numerous and unprepared audience: while among the written dialogues, there are some which, far from being popular or adapted to an ordinary understanding, are highly perplexing and abstruse. The Timæus does not confine itself to indirect hints, but delivers positive dogmas about the super-sensible world: though they are of a mystical cast, as we know that the oral lectures De Bono were also.
[101] Tennemann, Gesch. der Philos. ii. p. 205-220. Hermann, Ueber Plato’s Schriftsteller. Motive, pp. 290-294.
Hermann considers this reserve and double doctrine to be unworthy of Plato, and ascribes it to Protagoras and other Sophists, on the authority of a passage in the Theætêtus (152 C), which does not at all sustain his allegation.
Hermann considers “die akroamatischen Lehren als Fortsetzung und Schlussstein der schriftlichen, die dort erst zur vollen Klarheit principieller Auffassung erhoben wurden, ohne jedoch über den nämlichen Gegenstand, soweit die Rede auf denselben kommen musste, etwas wesentlich Verschiedenes zu lehren” (p. 293).
Characteristic of the oral lectures — that they were delivered in Plato’s own name. In what other respects they departed from the dialogues, we cannot say.
Towards filling up this gap, then, the oral lectures cannot be shown to lend any assistance. The cardinal point of difference between them and the dialogues was, that they were delivered by Plato himself, in his own name; whereas he never published any written composition in his own name. But we do not know enough to say, in what particular way this difference would manifest itself. Besides the oral lectures, delivered to a numerous auditory, it is very probable that Plato held special communications upon philosophy with a few advanced pupils. Here however we are completely in the dark. Yet I see nothing, either in these supposed private communications or in the oral lectures, to controvert what was said in the last page — that Plato’s affirmative philosophy is not fitted on to his negative philosophy, but grows out of other mental impulses, distinct and apart. Plato (as Aristotle tells us[102]) felt it difficult to determine, whether the march of philosophy was an ascending one toward the principia (ἀρχὰς), or a descending one down from the principia. A good philosophy ought to suffice for both, conjointly and alternately: in Plato’s philosophy, there is no road explicable either upwards or downwards, between the two: no justifiable mode of participation (μέθεξις) between the two disparate worlds — intellect and sense. The principia of Plato take an impressive hold on the imagination: but they remove few or none of the Platonic difficulties; and they only seem to do this because the Sokratic Elenchus, so effective whenever it is applied, is never seriously brought to bear against them.
[102] Aristot. Eth. Nik. i. 4, 5. εὖ γὰρ καὶ Πλάτων ἠπόρει τοῦτο καὶ ἐζήτει πότερον ἀπὸ τῶν ἀρχῶν ἢ ἐπὶ τὰς ἀρχάς ἐστιν ἡ ὁδός.
Apart from any result, Plato has an interest in the process of search and debate per se. Protracted enquiry is a valuable privilege, not a tiresome obligation.
With persons who complain of prolixity in the dialogue — of threads which are taken up only to be broken off, devious turns and “passages which lead to nothing” — of much talk “about it and about it,” without any peremptory decision from an authorised judge — with such complainants Plato has no sympathy. He feels a strong interest in the process of enquiry, in the debate per se: and he presumes a like interest in his readers. He has no wish to shorten the process, nor to reach the end and dismiss the question as settled.[103] On the contrary, he claims it as the privilege of philosophical research, that persons engaged in such discussions are noway tied to time; they are not like judicial pleaders, who, with a klepsydra or water-clock to measure the length of each speech, are under slavish dependence on the feelings of the Dikasts, and are therefore obliged to keep strictly to the point.[104] Whoever desires accurate training of mind must submit to go through a long and tiresome circuit.[105] Plato regards the process of enquiry as being in itself, both a stimulus and a discipline, in which the minds both of questioner and respondent are implicated and improved, each being indispensable to the other: he also represents it as a process, carried on under the immediate inspiration of the moment, without reflection or foreknowledge of the result.[106] Lastly, Plato has an interest in the dialogue, not merely as a mental discipline, but as an artistic piece of workmanship, whereby the taste and imagination are charmed. The dialogue was to him what the tragedy was to Sophokles, and the rhetorical discourse to Isokrates. He went on “combing and curling it” (to use the phrase of Dionysius) for as many years as Isokrates bestowed on the composition of the Panegyrical Oration. He handles the dialectic drama so as to exhibit some one among the many diverse ethical points of view, and to show what it involves as well as what it excludes in the way of consequence. We shall not find the ethical point of view always the same: there are material inconsistencies and differences in this respect between one dialogue and another.
[103] As an illustration of that class of minds which take delight in the search for truth in different directions, I copy the following passage respecting Dr. Priestley, from an excellent modern scientific biography. “Dr. Priestley had seen so much of the evil of obstinate adherence to opinions which time had rendered decrepit, not venerable — and had been so richly rewarded in his capacity of natural philosopher, by his adventurous explorations of new territories in science — that he unavoidably and unconsciously over-estimated the value of what was novel, and held himself free to change his opinions to an extent not easily sympathised with by minds of a different order. Some men love to rest in truth, or at least in settled opinions, and are uneasy till they find repose. They alter their beliefs with great reluctance, and dread the charge of inconsistency, even in reference to trifling matters. Priestley, on the other hand, was a follower after truth, who delighted in the chase, and was all his life long pursuing, not resting in it.