. . . The first one I made, for instance, which I think was important not only to my work, but which has become important to others, is that the most common denominator of music has nothing to do with pitch—that is to say counterpoint or harmony—but rather has to do with time. The reason it is the most common denominator is because it carries with itself the absence of sound. I’ve since found that there is no absence of sound, that noise is constantly taking place. But nevertheless, I was able to see that time was of more importance to me than pitch. . . .

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. . . the change . . . from pitch to time . . . came . . . [t]hrough the use of percussion instruments which had no access to pitch, but which allowed me to give a structure to the compositions . . .

. . . At the beginning for me it was the number of measures, and the measures were all of the same length. So I thought of a structure which would have the number of measures that has a square root. Therefore each unit of the whole piece could have the same proportions—be divided proportionally in the same way as every other unit, and in the same way as the whole composition. That struck me—and still strikes me—as being a convincing structure; not personal, but as factual as, say, the structure of a crystal.

John Cage