For God's sake! Cage is one of the geniuses of the 20th century. I think music can be defined as "before Cage" and "after Cage". Some of his more traditional works are incredible, and this kind of stuff is original and great.
By what standards is it "great"? Originality can become an obsession for some in the sense that it no longer serves any other purpose besides being different for the sake of it. Playing one note for a life time of man serves no musical purpose, so why did this "philosophy" have to be turned into music? This music cannot even be enjoyed, its only to create monotonous vibrations to exist in some closed spaces.
Cage taught composers to LIGHTEN UP! and stop being snobs.... and more importantly, he taught most modern composers out there that music is in the ear of the listener, and that everything can be music. Nothing better illustrates this than 4`33"... please, you can not agree with his ideas but just calling him retarded, or thinking that he did these things because he wouldnt be remembered for any other reason is just plain ignorance speaking.
His attitude towards music or art forms in general might be an admirable thing in the sense of liberating people's views from the old conceptions of what art is, but the actual fruit of this is mostly seen in spawning of pseudoartists, rather than real artistic revolution. Ever since postmodernism introduced the idea that anything can be art, people have adopted this thought model only to aid in their uncertainty towards their own creations - self-criticism has vanished, nobody practices healthy doubt, and every irrational collasion of random items can be presented as "art", no matter how little actual intuition, innovation or idea of some abstract meaning was involved in creation of the work. Art no longer is balsam for the soul, it has become a toilet for people's random unfounded thoughts and feelings, and the pipes lead to modern art museums and galleries and other popular neo-art scenes.
Even without his writings he would be remembered for his works for percussion ensambles or prepared piano which are some of the most important things in the 20th century repertoire; not to mention that almost all of the greates composers after him were heavily influenced by him.
Sorry, but that is laughable. Rachmaninoff died in 1943, Prokofiev in 1953, Sibelius in 1957 - only to bring in a few personal favourites. Personally, I would rank about any piece from these composers over anything that John Cage created in terms of importance in musical sense. Other than being heavily depressed for most of his life, Rachmaninoff was probably not very philosophical in cosmic matters, but his music is by far more beautiful than anything that John Cage created. Before you ask, I haven't heard all of Cage's repertoire (same goes for Rachmaninoff), but I have heard one piece for prepared piano and the album In a Landscape, besides other miscellanous stuff. Prepared piano was interesting percussively, but failed to stimulate me musically. Innovative technical expansion of limits of instruments, not-so-innovative use of it. I don't know about the influence part, so I'll just take what you say as the truth, for I have no reason to oppose every suggestion that Cage was an important asset for the world of music/art. That is most probably true, no matter how pointless I think his musical concretizations are.
His ideas were of such a revolutionary nature that I believe that to dare to call him retarded, backwards and to speak of him in such a derogatory manner is akin to doing the same about Beethoven or Debussy.
I never said Cage was backwards, though I still think whoever's decision to actualize 600 years long performance was retarded. Again, if speaking of music, I value those two composers mentioned far above Mr. Cage.