American avant-garde composer John Cage (1912-1992) experimented with the nature of sound and devised new systems of musical notation. His innovative ideas on composition and performance influenced musicians, painters, and choreographers.

John Cage questioned all musical preconceptions inherited from the 19th century, and he flourished in an atmosphere of controversy. The teacher-composer Arnold Schoenberg once called him "not a composer, but an inventor--of genius." He received awards and grants; a few important music critics wrote perceptively and enthusiastically about his works. However, to most of the public and even to many musicians his compositions--especially the late ones--remain baffling and outrageous, an anarchic world of noise that cannot even qualify as music.

To Cage, "everything we do is music." He believed that the function of art is to imitate nature's manner of operation, and to this end he tried to make music that resembles forms of organic growth--taking into...