Socrates: We cannot, therefore, agree in the opinion of him who says that the syllable can be known and expressed, but not the letters.
Theaetetus: Certainly not; if we may trust the argument.
Socrates: Well, but will you not be equally inclined to disagree with him, when you remember your own experience in learning to read?
Theaetetus: What experience?
Socrates: Why, that in learning you were kept trying to distinguish the separate letters both by the eye and by the ear, in order that, when you heard them spoken or saw them written, you might not be confused by their position.
Theaetetus: Very true.
Socrates: And is the education of the harp-player complete unless he can tell what string answers to a particular note; the notes, as everyone would allow, are the elements or letters of music?
Theaetetus: Exactly.
Socrates: Then, if we argue from the letters and syllables which we know to other simples and compounds, we shall say that the letters or simple elements as a class are much more certainly known than the syllables, and much more indispensable to a perfect knowledge of any subject; and if someone says that the syllable is known and the letter unknown, we shall consider that either intentionally or unintentionally he is talking nonsense?
Theaetetus: Exactly.
Socrates: And there might be given other proofs of this belief, if I am not mistaken. But do not let us in looking for them lose sight of the question before us, which is the meaning of the statement, that right opinion with rational definition or explanation is the most perfect form of knowledge.
Theaetetus: We must not.
Socrates: Well, and what is the meaning of the term “explanation”? I think that we have a choice of three meanings.
Theaetetus: What are they?
Socrates: In the first place, the meaning may be, manifesting one’s thought by the voice with verbs and nouns, imaging an opinion in the stream which flows from the lips, as in a mirror or water. Does not explanation appear to be of this nature?
Theaetetus: Certainly; he who so manifests his thought, is said to explain himself.
Socrates: And everyone who is not born deaf or dumb is able sooner or later to manifest what he thinks of anything; and if so, all those who have a right opinion about anything will also have right explanation; nor will right opinion be anywhere found to exist apart from knowledge.
Theaetetus: True.
Socrates: Let us not, therefore, hastily charge him who gave this account of knowledge with uttering an unmeaning word; for perhaps he only intended to say, that when a person was asked what was the nature of anything, he should be able to answer his questioner by giving the elements of the thing.
Theaetetus: As for example, Socrates … ?
Socrates: As, for example, when Hesiod says that a wagon is made up of a hundred planks. Now, neither you nor I could describe all of them individually; but if anyone asked what is a wagon, we should be content to answer, that a wagon consists of wheels, axle, body, rims, yoke.
Theaetetus: Certainly.
Socrates: And our opponent will probably laugh at us, just as he would if we professed to be grammarians and to give a grammatical account of the name of Theaetetus, and yet could only tell the syllables and not the letters of your name—that would be true opinion, and not knowledge; for knowledge, as has been already remarked, is not attained until, combined with true opinion, there is an enumeration of the elements out of which anything is composed.
Theaetetus: Yes.
Socrates: In the same general way, we might also have true opinion about a wagon; but he who can describe its essence by an enumeration of the hundred planks, adds rational explanation to true opinion, and instead of opinion has art and knowledge of the nature of a wagon, in that he attains to the whole through the elements.