One day I said to myself that it would be better to get rid of all that—melody, rhythm, harmony, etc. This was not a negative thought and did not mean that it was necessary to avoid them, but rather that, while doing something else, they would appear spontaneously. We had to liberate ourselves from the direct and peremptory consequence of intention and effect, because the intention would always be our own and would be circumscribed, when so many other forces are evidently in action in the final effect.

quoted in Classic Essays on Twentieth-Century Music, ISBN 0028645812