4.33 -- John Cage

Wanna hear about the quietest piece of music ever composed? It's by John Cage
(1912-1992), who was at the center of the US avant-garde scene for several decades, and has probably had a greater influence on world music than any other 20th-century American composer. This three-movement composition, in which a performer sits at a piano for four minutes and thirty three seconds intentionally making no sounds, is possibly his most famous piece. The idea behind the work is that the audience should be driven to appreciate the ambient sounds around them. It was a reflection of the influence of Zen Buddhism, which Cage studied since the late forties.              (songfacts)

4′33″  is a three-movement composition by American experimental composer John Cage . It was composed in 1952 for any instrument, and the score instructs the performer not to play the instrument during the entire duration of the piece throughout the three movements . The piece purports to consist of the sounds of the environment that the listeners hear while it is performed, although it is commonly perceived as "four minutes thirty-three seconds of silence".

4′33″ is Cage's most famous and most controversial composition, and by far the most well known of the numerous musical works that consist mainly of silence.

4′33″ became for Cage the epitome of his idea that any sounds constitute, or may constitute, music.^[7] It was also a reflection of the influence of Zen Buddhism, which Cage studied since the late 1940s. In a 1982 interview, and on numerous other occasions, Cage stated that 4′33″ was, in his opinion, his most important work.                                                                                                                 
                                                                                                         (wikipedia)  

                (google  images)  

Zen is a school of Mahayana Buddhism which originated in China during the 6th century CE as Chán. From China, Zen spread south to Vietnam, to Korea and east to Japan.

The word Zen is from the Japanese pronunciation of the Middle Chinese word 禪 Dzyen , which in turn is derived from the Sanskrit word dhyāna, which can be approximately translated as "absorption" or "meditative state".

Zen emphasizes the personal expression of experiential wisdom in the attainment of enlightenment. As such, it de-emphasizes adherence to standardized theoretical knowledge in favor of direct self-realization through meditation and dharma practice.
The teachings of Zen include various sources of Mahāyāna thought    (wikipedia)