John Milton Cage Jr. (September 5, 1912 – August 12, 1992) was an American composer,
music theorist, writer, and artist. A pioneer of
indeterminacy in music,
electroacoustic music, and
non-standard use of musical instruments, Cage was one of the leading figures of the post-war
avant-garde. Critics have lauded him as one of the most influential American composers of the 20th century. He was also instrumental in the development of
modern dance, mostly through his association with choreographer
Merce Cunningham, who was also Cage's romantic partner for most of their lives.