Cage, who died in 1992 just shy of his 80th birthday, created a stir in the music world in 1952 with the premiere of the now famous, in some circles notorious, 4'33" in which a pianist sat at a piano in upstate New York and played no notes for the four minutes and 33 seconds specified in the title.

David Tudor lifted the piano lid at the beginning of each of three movements and lowered it at the end, according to pre-set timings, taking care not to make a sound. The open-air Maverick Concert Hall in Woodstock was nevertheless filled with the outdoor chirpings of insects, the rustlings of the audience and perhaps the psychic vibes of outraged concertgoers as they began to realize he wasn't going to play a single note.

"For a lot of people there's the indignation that an artist is getting paid for something he didn't do," said Kyle Gann, author of "No Such Thing as Silence" (Yale University Press), a book about Cage, his piece and its enormous influence on music in the latter half of the 20th century.

Cage recounted that some of his friends never spoke to him again, but his piece, sometimes inaccurately called "Silence", had an impact far beyond anything he could have imagined.

Cage had established what Gann uses for the title of his book, that there is no such thing as silence, bringing music into the new mainstream of the late 20th century in which Cage's friend Robert Rauschenberg painted all-white canvases, Samuel Beckett wrote a play in which two men wait for someone who never arrives and people's expectations are turned on their head, forcing them to re-engage with art and the world around them.

"I think a lot of non-classical musicians see the poetry of it (4'33") and the really simple idea of dividing a silence into three parts and listening to the landscape," Gann said in a telephone interview from his home near Bard College in Annandale-on-Hudson, New York, where he is an associate professor in the music department.

"It had an appeal the more sophisticated would frown on but a lot of people with no axes to grind find it an attractively poetic idea, and it's something anybody can do, anybody can perform it, it can be performed anywhere and rock groups have really made a thing of it," Gann said. Cage said he sometimes performed it in his head.

Gann was struck that when the BBC Symphony Orchestra did it as an orchestral piece in London in 2004, "people waited to cough between the movements" - and also wrote biting criticisms on a BBC blog, calling the piece "absolutely ridiculous", "clearly a gimmick" and demanding to know why BBC public licensing fees were being used to pay for such things.

INSPIRATIONAL FIGURE

Although he remains controversial two decades after his death, Cage has received the centenary tributes due a major cultural figure, including a festival in Washington, DC, in September, a conference in York, England in November, and an exhibit opening in October at the Philadelphia Museum of Art to show Dadaist artist Marcel Duchamp's links to Cage and others.

Cage's contributions to music, including his invention of the prepared piano by inserting screws, bamboo and other odds and ends into the strings to make a more percussive sound, flying a blimp around a balcony in one of his "Europeras", and staging a "happening" in North Carolina in 1952 where Rauschenberg played songs on a phonograph while Cage stood on a ladder and gave a lecture, have become part of the Cage canon.

But nowhere could his spirit have been more alive than in a packed music cafe in north London this past weekend where some 40 musicians, seated or standing as often as not amid the audience, played music by Cage and pieces influenced by him.

Cage's Four6 performed by four musicians playing amplified piano, turntables and electronics, a chorded zither and more electronics started off with rustling similar to what the audience at Maverick staring at the silent piano might have heard and built to a climax of harsh and sometimes grating sounds typical of later Cage before fading away.

According to the website of innovative British music label Another Timbre (www.anothertimbre.com), which organized the event, the piece employs "chance-derived time brackets", one of Cage's favorite techniques in his later period, to determine when each musician plays one of several pre-selected sounds.

"The result felt like someone had neatly arranged forty-eight rusty old cars into precise formations at a scrapyard," a music blogger said colorfully, and intending high praise.

Playing the Cage piece, as well as the rest of the programme, demanded huge concentration by players and audience alike, but Patrick Farmer, 29, one of the musicians in Four6, said that even if he has become a historical figure, Cage had opened the doors to a new way of looking at and creating music.

"He was often in the right place at the right time and there was a lot of luck involved," Farmer said. "But at the same time, probably someone else could have been in that same situation and wouldn't have had the openness and confidence and almost the audacity that Cage had." (Editing by Paul Casciato)

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