What’s the Deal with John Cage's 4'33''?

In 4'33'' by the American composer John Cage (1912 – 1992), the musician or musicians do not play a single note. The three movements, Tacet 1-3, last in total exactly four minutes and thirty-three seconds, and since the premiere in 1952, major discussion has repeatedly been sparked: Is this music?

If you follow the composer’s notes, 4'33'' is not a "silent" piece of music at all, but rather a piece of music composed of ambient noise. There is no such thing as absolute stillness.

The listener is crucial to the performance, they are challenged to hear something, when there seems to be nothing, at least no intentional noises. This is exactly what Cage describes in the audience reactions at the premiere:

“People began to whisper to one another, some began to walk out. They didn't laugh - they were just irritated when they realised that nothing was going to happen. Even 30 years later they have not forgotten: they are still angry”

Related:

• What Exactly is a Decibel? What Volume is Harmful?