grindy

Silence is an element of music. I think everybody agrees, that a moment of silence can be quite beneficial for the development of a piece. Think of a pause before all hell breaks loose in some song... That can be quite powerful.
And since silence can be an element of music, then why not stretch it and leave sounds out of it altogether? So, definitely music in my opinion.
After all, a lot of lowercase or onkyo-kei are mostly silence, so why draw a line there?
Sure, 4'33 is a concept piece, nobody sits down to listen to it at home. (Although one could say we listen to it most of the time.) But still music.
Once again, whether it's good music or not, whether it's clever or stupid and lazy, is another thing altogether.

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