"Chance operations forever altered Cage's aesthetic of silence. Where before he had seen silence as impassiveness, flatness or aimlessness, he now saw it as a complete negation of the composer's will, tastes and desires. Silence had nothing to do with the acoustic surface of events, but instead was a function of the inner forces that prompted the sounds. Acoustic silence changed from being an absence of sound to being an absence of intended sound. Cage turned deliberately towards the world of unintended sound, announcing that his goal was to be 'free of individual taste and memory'. But such sweeping statements were somewhat misleading. Cage employed chance operations only in the ordering and coordination of musical events. The selection of materials, the planning of structure and the overall musical stance were still shaped by his stylistic predilections. What he had learned by using chance operations in a work like the Concerto was that, given a set of sounds and a structure built on lengths of time, any arrangement of the sounds and silences would be valid and interesting. Chance, by helping to avoid habitual modes of thinking, could in fact produce something fresher and more vital than that which the composer might have invented alone."
ANDREW STILLER, Cage, John, Chance, The New Grove Dictionary of Music Online ed. L. Macy, Accessed [Feb. 3, 2003], http://www.grovemusic.com