But there is another general division under which his art may be also supposed to fall, and that is purification; and from purification is descended education, and the new principle of education is to interrogate men after the manner of Socrates, and make them teach themselves. Here again we catch a glimpse rather of a Socratic or Eristic than of a Sophist in the ordinary sense of the term. And Plato does not on this ground reject the claim of the Sophist to be the true philosopher. One more feature of the Eristic rather than of the Sophist is the tendency of the troublesome animal to run away into the darkness of Not-being. Upon the whole, we detect in him a sort of hybrid or double nature, of which, except perhaps in the Euthydemus of Plato, we find no other trace in Greek philosophy; he combines the teacher of virtue with the Eristic; while in his omniscience, in his ignorance of himself, in his arts of deception, and in his lawyer-like habit of writing and speaking about all things, he is still the antithesis of Socrates and of the true teacher.
II. The question has been asked, whether the method of 'abscissio infinti,' by which the Sophist is taken, is a real and valuable logical process. Modern science feels that this, like other processes of formal logic, presents a very inadequate conception of the actual complex procedure of the mind by which scientific truth is detected and verified. Plato himself seems to be aware that mere division is an unsafe and uncertain weapon, first, in the Statesman, when he says that we should divide in the middle, for in that way we are more likely to attain species; secondly, in the parallel precept of the Philebus, that we should not pass from the most general notions to infinity, but include all the intervening middle principles, until, as he also says in the Statesman, we arrive at the infima species; thirdly, in the Phaedrus, when he says that the dialectician will carve the limbs of truth without mangling them; and once more in the Statesman, if we cannot bisect species, we must carve them as well as we can. No better image of nature or truth, as an organic whole, can be conceived than this. So far is Plato from supposing that mere division and subdivision of general notions will guide men into all truth.
Plato does not really mean to say that the Sophist or the Statesman can be caught in this way. But these divisions and subdivisions were favourite logical exercises of the age in which he lived; and while indulging his dialectical fancy, and making a contribution to logical method, he delights also to transfix the Eristic Sophist with weapons borrowed from his own armoury. As we have already seen, the division gives him the opportunity of making the most damaging reflections on the Sophist and all his kith and kin, and to exhibit him in the most discreditable light.
Nor need we seriously consider whether Plato was right in assuming that an animal so various could not be confined within the limits of a single definition. In the infancy of logic, men sought only to obtain a definition of an unknown or uncertain term; the after reflection scarcely occurred to them that the word might have several senses, which shaded off into one another, and were not capable of being comprehended in a single notion. There is no trace of this reflection in Plato. But neither is there any reason to think, even if the reflection had occurred to him, that he would have been deterred from carrying on the war with weapons fair or unfair against the outlaw Sophist.
III. The puzzle about 'Not-being' appears to us to be one of the most unreal difficulties of ancient philosophy. We cannot understand the attitude of mind which could imagine that falsehood had no existence, if reality was denied to Not-being: How could such a question arise at all, much less become of serious importance? The answer to this, and to nearly all other difficulties of early Greek philosophy, is to be sought for in the history of ideas, and the answer is only unsatisfactory because our knowledge is defective. In the passage from the world of sense and imagination and common language to that of opinion and reflection the human mind was exposed to many dangers, and often
'Found no end in wandering mazes lost.'
On the other hand, the discovery of abstractions was the great source of all mental improvement in after ages. It was the pushing aside of the old, the revelation of the new. But each one of the company of abstractions, if we may speak in the metaphorical language of Plato, became in turn the tyrant of the mind, the dominant idea, which would allow no other to have a share in the throne. This is especially true of the Eleatic philosophy: while the absoluteness of Being was asserted in every form of language, the sensible world and all the phenomena of experience were comprehended under Not-being. Nor was any difficulty or perplexity thus created, so long as the mind, lost in the contemplation of Being, asked no more questions, and never thought of applying the categories of Being or Not-being to mind or opinion or practical life.
But the negative as well as the positive idea had sunk deep into the intellect of man. The effect of the paradoxes of Zeno extended far beyond the Eleatic circle. And now an unforeseen consequence began to arise. If the Many were not, if all things were names of the One, and nothing could be predicated of any other thing, how could truth be distinguished from falsehood? The Eleatic philosopher would have replied that Being is alone true. But mankind had got beyond his barren abstractions: they were beginning to analyze, to classify, to define, to ask what is the nature of knowledge, opinion, sensation. Still less could they be content with the description which Achilles gives in Homer of the man whom his soul hates —
os chi eteron men keuthe eni phresin, allo de eipe.
For their difficulty was not a practical but a metaphysical one; and their conception of falsehood was really impaired and weakened by a metaphysical illusion.
The strength of the illusion seems to lie in the alternative: If we once admit the existence of Being and Not-being, as two spheres which exclude each other, no Being or reality can be ascribed to Not-being, and therefore not to falsehood, which is the image or expression of Not-being. Falsehood is wholly false; and to speak of true falsehood, as Theaetetus does (Theaet.), is a contradiction in terms. The fallacy to us is ridiculous and transparent, – no better than those which Plato satirizes in the Euthydemus. It is a confusion of falsehood and negation, from which Plato himself is not entirely free. Instead of saying, 'This is not in accordance with facts,' 'This is proved by experience to be false,' and from such examples forming a general notion of falsehood, the mind of the Greek thinker was lost in the mazes of the Eleatic philosophy. And the greater importance which Plato attributes to this fallacy, compared with others, is due to the influence which the Eleatic philosophy exerted over him. He sees clearly to a certain extent; but he has not yet attained a complete mastery over the ideas of his predecessors – they are still ends to him, and not mere instruments of thought. They are too rough-hewn to be harmonized in a single structure, and may be compared to rocks which project or overhang in some ancient city's walls. There are many such imperfect syncretisms or eclecticisms in the history of philosophy. A modern philosopher, though emancipated from scholastic notions of essence or substance, might still be seriously affected by the abstract idea of necessity; or though accustomed, like Bacon, to criticize abstract notions, might not extend his criticism to the syllogism.
The saying or thinking the thing that is not, would be the popular definition of falsehood or error. If we were met by the Sophist's objection, the reply would probably be an appeal to experience. Ten thousands, as Homer would say (mala murioi), tell falsehoods