ONE COULD SPEAK of the minor harmony produced by the vibration of one string against another as the ratio of their oscillations. It’s a mathematical relation. String on string is sound and song is sound. The reflection of a bluebird in a window is an optical calculation. A blue pixel here, a blue pixel there — scientists make rainbows every day:
But what is song?Do songbirds cry?
And if so, does it sound like a song?
Down which side of what pane do whose tears drop blue rain?
From which grew whose grim portrait?
Who breathes there?
What is one?
What beats there?
What is two?
Those are more difficult questions.