Columbia subject headings:
Cage, John.
Music--Philosophy and aesthetics--History--20th century.
Harvard subject headings:
Cage, John--Aesthetics.
Cage, John--Philosophy.
Composers--United States--Biography
Listening (Philosophy)
Music theorists--United States--Biography.
Music--Philosophy and aesthetics
Princeton subject headings:
Cage, John.
Music--Philosophy and aesthetics--History--20th century.