John Cage already covered silence. In his "composition" 4:33. It was "written" and "performend" for the first time in 1952. The first "performance" was by pianist David Tudor.

Here is a descrpition that I copy and pasted.

"For the performance Tudor placed the hand-written score, which was in conventional notation with blank measures, on the piano and sat motionless as he used a stopwatch to measure the time of each movement. The score indicated three silent movements, each of a different length, but when added together totalled four minutes and thirty-three seconds. Tudor signaled its commencement by lowering the keyboard lid of the piano. The sound of the wind in the trees entered the first movement. After thirty seconds of no action, he raised the lid to signal the end of the first movement. It was then lowered for the second movement, during which raindrops pattered on the roof. The score was in several pages, so he turned the pages as time passed, yet playing nothing at all. The keyboard lid was raised and lowered again for the final movement, during which the audience whispered and muttered.

When Tudor finished, raising the keyboard lid and himself from the piano, the audience burst into an uproar -- "infuriated and dismayed," according to the reports. Even in the midst of an avant garde concert attended by modern artists, 4'33" was considered "going too far".

Note that 4'33" is incorrectly listed as "4 pieces" on the printed program. It is easy to see how the original list of timings, listed under the heading 4'33", would have been confused by someone who typed the program as being four pieces with their timings as titles. Nevertheless, the timings of the movements are a crucial record."