By Water & Blood

Chapter 13

'You remind me very correctly, said I; for music certainly contained nothing of the kind. But what can there be of this character, my excellent Glaucon? For, I think, we regarded all the arts as mechanical. Of course.'

Then further on he adds: ^[32]

'We must never let those whom we are to educate attempt any imperfect form of science that has not reached the point that all ought to attain, as we were saying just now about astronomy. Or do you not know that they treat harmony also in this way? For while they measure and compare with each other the notes and concords that are merely heard, they labour, like the astronomers, on a useless task.

'Yes, by heaven! said he, and it is ludicrous to see how they name certain condensed intervals, and lay their ears on one side, as if trying to catch a note from their neighbours; and some of them say that they can still hear an intermediate sound, and that this is the very smallest interval which should be used in measuring, while others doubt this and say that they now sound alike, and both set their ears before their mind.

'You mean, said I, those good men who are always teasing and torturing the strings, and screwing them up on the pegs. But that the metaphor may not be extended too far about the beats given by the plectrum, and the assent, and dissent, and petulance of the strings, I drop the metaphor, and say that I do not mean these men, but those others whom we said just now that we would consult about harmony. For they do the same as the astronomers; they investigate the numerical relations in the harmonies which fall upon the ears, but they do not rise to problems, to examine what numbers are harmonious, and what not, and the reason in either case.'

But now let this suffice in the way of preface to our defence that we have not without right judgement neglected the useless learning of such subjects as these. Let us then make at once a new beginning and examine the mutual contradictions in doctrine of the aforesaid physical philosophers. Now Plutarch has collected together the opinions of all the Platonists and Pythagoreans alike, and of the still earlier physical philosophers as they were called, and again of the more recent Peripatetics, and Stoics, and Epicureans, and written them in a work which he entitled Of the Physical Doctrines approved by Philosophers, from which I shall make the following quotations: ^[33]