Credo in Us di John Cage.

Dated: New York, July, 1942. Revised October 1942
Instrumentation: 4 performers: pianist; 2 percussionists on muted gongs, tin cans, electric buzzer and tom-toms; one performers who plays a radio or phonograph;
Duration: 12′
Premiere and performer(s): August 1, 1942 at Bennington College in Bennington, Vermont, performed with the choreography by Merce Cunningham and Jean Erdman

The work was composed in the phraseology of the dance by Cunningham and Erdman. For the first time Cage uses records or radios, incorporating music of other composers in his own works. He suggests music by Dvorak, Beethoven, Sibelius or Shostakovich. Cage describes the work as a suite with a satirical character.
Jean Erdman recalls that for the first performance a ‘tack-piano’ was used (a piano with tumbtacks inserted onto the felt of the hammers). The pianist mutes the strings at times or plays the piano body (as a percussionist).