I've been a fan of John Cage's work for a long time. However, for me his oeuvre kind of splits into two halves. Many of his early works (say, up to the mid 1950s?) can be listened to as decent works of modern music in the classical tradition. They are "composed"; they have internal structure and purpose. Sonatas and Interludes is a great example; Four Walls is another.
After 4'33", however, a lot of his work seems to me to be aiming only towards achieving some sort of ideological purity in explicating Cage's philosophy of indeterminacy. To some extent, once you've heard a few of these pieces, you've heard them all. The Freeman Etudes in particular have always been, for me, one of Cage's least listenable pieces.
It reminds me of a couple of concepts that I think Cage might have resonated with. One is "Wittgenstein's ladder" (http://c2.com/cgi/wiki?WittgensteinsLadder): "My propositions serve as elucidations in the following way: anyone who understands me eventually recognizes them as nonsensical, when he has used them - as steps - to climb beyond them. He must, so to speak, throw away the ladder after he has climbed up it." In other words, once you "get" what Cage was trying to say (in, e.g., 4'33"), you've gotten it, and you don't really need to keep listening.
Along the same lines, what Alan Watts said about using psychedelic drugs: "Psychedelic experience is only a glimpse of genuine mystical insight, but a glimpse which can be matured and deepened by the various ways of meditation in which drugs are no longer necessary or useful. If you get the message, hang up the phone. For psychedelic drugs are simply instruments, like microscopes, telescopes, and telephones. The biologist does not sit with eye permanently glued to the microscope, he goes away and works on what he has seen..." The analogy might be a little bit of a stretch, but Cage's music is something like an "instrument" that gives "a glimpse of genuine [musical] insight": the fact that beautiful, indeterminate music is happening all around you all the time, if you stop and listen to it.
I think the same about some modern art, such as Duchamp's urinal, or Craig-Martin's oak tree. Once you understand what the artist is trying to say, there is no need ever to see the work again.
Although it gets me into trouble, I tend to divide art into "craft", where skill is important, and "visual philosophy", where the message is the thing, and skill is often secondary. And I have to say that I prefer that to the Old Masters!
https://www.youtube.com/watch?v=03ze845nRYc
I consider myself a music lover, but people listening to 46 minutes of that while reading it to determine not one note was missed I don't understand.
For those that like Cage's work, what do you appreciate about it and do you listen to his pieces often?