Stranger: Why, because they are compelled to use the words “to be,” “apart,” “from others,” “in itself,” and ten thousand more, which they cannot give up, but must make the connecting links of discourse; and therefore they do not require to be refuted by others, but their enemy, as the saying is, inhabits the same house with them; they are always carrying about with them an adversary, like the wonderful ventriloquist, Eurycles, who out of their own bellies audibly contradicts them.
Theaetetus: Precisely so; a very true and exact illustration.
Stranger: And now, if we suppose that all things have the power of communion with one another—what will follow?
Theaetetus: Even I can solve that riddle.
Stranger: How?
Theaetetus: Why, because motion itself would be at rest, and rest again in motion, if they could be attributed to one another.
Stranger: But this is utterly impossible.
Theaetetus: Of course.
Stranger: Then only the third hypothesis remains.
Theaetetus: True.
Stranger: For, surely, either all things have communion with all; or nothing with any other thing; or some things communicate with some things and others not.
Theaetetus: Certainly.
Stranger: And two out of these three suppositions have been found to be impossible.
Theaetetus: Yes.
Stranger: Everyone then, who desires to answer truly, will adopt the third and remaining hypothesis of the communion of some with some.
Theaetetus: Quite true.
Stranger: This communion of some with some may be illustrated by the case of letters; for some letters do not fit each other, while others do.
Theaetetus: Of course.
Stranger: And the vowels, especially, are a sort of bond which pervades all the other letters, so that without a vowel one consonant cannot be joined to another.
Theaetetus: True.
Stranger: But does everyone know what letters will unite with what? Or is art required in order to do so?
Theaetetus: Art is required.
Stranger: What art?
Theaetetus: The art of grammar.
Stranger: And is not this also true of sounds high and low?—Is not he who has the art to know what sounds mingle, a musician, and he who is ignorant, not a musician?