To begin with, a nerve stimulus is transferred into an image: first metaphor. The image, in turn, is imitated in a sound: second metaphor. And each time there is a complete overleaping of one sphere, right into the middle of an entirely new and different one.
One can imagine a man who is totally deaf and has never had a sensation of sound and music. Perhaps such a person will gaze with astonishment at Chladni’s sound figures; perhaps he will discover their causes in the vibrations of the string and will now swear that he must know what men mean by “sound.”
It is this way with all of us concerning language; we believe that we know something about the things themselves when we speak of trees, colors, snow, and flowers; and yet we possess nothing but metaphors for things–metaphors which correspond in no way to the original entities.
Friedrich Nietzsche – On Truth and Lies in a Nonmoral Sense