[The music of the spheres] is the only sound which has never for one split second ceased in any part of the universe; with this positive we have no negative to contrast. Presumably if (per impossibile) it ever did stop, then with terror and dismay, with a dislocation of our whole auditory life, we should feel that the bottom had dropped out of our lives. But it never does. The music which is too familiar to be heard enfolds us day and night and in all ages.
- C. S. Lewis, 'Imagination and Thought in the Middle Ages'