One of the twentieth century's most influential and iconoclastic protagonists, John Cage (1912-1992) may be described not so much as a composer, artist and author, as a thinker who applied his ideas equivalently to sound, visual art and writing. As with his music, the use of chance operations--in particular via the Chinese Book of Changes , or I Ching --was central to Cage's approach to visual art, determining technique, the placement of forms and...