Of these Eristics, whether Cynics or Megarians, several characteristics are found in Plato:—
1. They pursue verbal oppositions; 2. they make reasoning impossible by their over-accuracy in the use of language; 3. they deny predication; 4. they go from unity to plurality, without passing through the intermediate stages; 5. they refuse to attribute motion or power to Being; 6. they are the enemies of sense;—whether they are the “friends of ideas,” who carry on the polemic against sense, is uncertain; probably under this remarkable expression Plato designates those who more nearly approached himself, and may be criticizing an earlier form of his own doctrines. We may observe (1) that he professes only to give us a few opinions out of many which were at that time current in Greece; (2) that he nowhere alludes to the ethical teaching of the Cynics—unless the argument in the “Protagoras,” that the virtues are one and not many, may be supposed to contain a reference to their views, as well as to those of Socrates; and unless they are the school alluded to in the “Philebus,” which is described as “being very skilful in physics, and as maintaining pleasure to be the absence of pain.” That Antisthenes wrote a book called Physicus, is hardly a sufficient reason for describing them as skilful in physics, which appear to have been very alien to the tendency of the Cynics.
The Idealism of the fourth century before Christ in Greece, as in other ages and countries, seems to have provoked a reaction towards Materialism. The maintainers of this doctrine are described in the “Theaetetus” as obstinate persons who will believe in nothing which they cannot hold in their hands, and in the “Sophist” (246 D) as incapable of argument. They are probably the same who are said in the Tenth Book of the Laws (888 E) to attribute the course of events to nature, art, and chance. Who they were, we have no means of determining except from Plato’s description of them. His silence respecting the Atomists might lead us to suppose that here we have a trace of them. But the Atomists were not Materialists in the grosser sense of the term, nor were they incapable of reasoning; and Plato would hardly have described a great genius like Democritus in the disdainful terms which he uses of the Materialists. Upon the whole, we must infer that the persons here spoken of are unknown to us, like the many other writers and talkers at Athens and elsewhere, of whose endless activity of mind Aristotle in his Metaphysics has preserved an anonymous memorial.
V. The “Sophist” is the sequel of the “Theaetetus,” and is connected with the “Parmenides” by a direct allusion (compare Introductions to “Theaetetus” and “Parmenides”). In the “Theaetetus” we sought to discover the nature of knowledge and false opinion. But the nature of false opinion seemed impenetrable; for we were unable to understand how there could be any reality in Not-being. In the “Sophist” the question is taken up again; the nature of Not-being is detected, and there is no longer any metaphysical impediment in the way of admitting the possibility of falsehood. To the “Parmenides,” the “Sophist” stands in a less defined and more remote relation. There human thought is in process of disorganization; no absurdity or inconsistency is too great to be elicited from the analysis of the simple ideas of Unity or Being. In the “Sophist” the same contradictions are pursued to a certain extent, but only with a view to their resolution. The aim of the dialogue is to show how the few elemental conceptions of the human mind admit of a natural connection in thought and speech, which Megarian or other sophistry vainly attempts to deny.
True to the appointment of the previous day, Theodorus and Theaetetus meet Socrates at the same spot, bringing with them an Eleatic Stranger, whom Theodorus introduces as a true philosopher. Socrates, half in jest, half in earnest, declares that he must be a god in disguise, who, as Homer would say, has come to earth that he may visit the good and evil among men, and detect the foolishness of Athenian wisdom. At any rate he is a divine person, one of a class who are hardly recognized on earth; who appear in divers forms—now as statesmen, now as sophists, and are often deemed madmen. “Philosopher, statesman, sophist,” says Socrates, repeating the words—“I should like to ask our Eleatic friend what his countrymen think of them; do they regard them as one, or three?”
The Stranger has been already asked the same question by Theodorus and Theaetetus; and he at once replies that they are thought to be three; but to explain the difference fully would take time. He is pressed to give this fuller explanation, either in the form of a speech or of question and answer. He prefers the latter, and chooses as his respondent Theaetetus, whom he already knows, and who is recommended to him by Socrates.
We are agreed, he says, about the name Sophist, but we may not be equally agreed about his nature. Great subjects should be approached through familiar examples, and, considering that he is a creature not easily caught, I think that, before approaching him, we should try our hand upon some more obvious animal, who may be made the subject of logical experiment; shall we say an angler? “Very good.”
In the first place, the angler is an artist; and there are two kinds of art—productive art, which
