Why are people prepared to sit silently for three hours listening to an opera performance of which they do not understand a word and of which they seldom know the plot? Partly, of course, because it is a display of skill, like a football match. But chiefly, I think, because it is irrational. ‘What is too silly to be said may be sung’  well, yes; but also what is too subtle, or too deeply felt, or too revealing or too mysterious, these things also can be sung and only be sung.
Kenneth Clark 1903-1983
 Beaumarchais, although often ascribed to Voltaire. Joseph Addison said something similar earlier but to a smaller audience.