John Cage: Complete Piano MusicMD&G Recording, 18 CDsAmong John Cage’s multiple legacies, the piano looms largest. Bursting into music in California without the benefit or inhibition of a European tradition, Cage stuck nails and bits of wood between the strings of a concert grand to create a ‘prepared piano’, emitting quasi-oriental sounds of hypnotic fascination. That invention dates from 1940s Los Angeles, where the ungainly Cage was taking music lessons from the uncomprehending old-revolutionary, Arnold Schoenberg.At the end of that decade, again at the piano, Cage introduced the young Europeans Boulez, Stockhausen and Berio at the Darmstadt summer school to new freedoms. In Music of Changes, he gave the performer a range of score options and left him or her to decide on the moment which should be played. In 4’33”, Cage sat a pianist at the keyboard with instructions to do nothing for four minutes and 33 seconds, encouraging the audience to appreciate the ambience.The climax of his work for piano was Winter Music, written for ten pianos in 1957 and dedicated to the artists Robert Rauschenberg and Jasper Johns, followed by a 1958 piano concerto – after which he gave up the instrument for three decades. Cage, whose birth centenary falls this year, remains one of the most diverse and perplexing influences on western music in modern times, and not on music alone. His impact on dance, pop and the visual arts was equally impressive, and continues to grow two decades after his death. DJs who manipulate turntables in dark discos are unware that they do so courtesy of a 1938 Cage inspiration.Steffen Schleiermacher, a German pianist and composer who poses for the camera between Californian cactuses on his album booklet, worked assiduously over five years to play all of Cage’s published work for piano, along with some that was considered unsuitable for publication. In tune with Cage’s outlook, he specifies that each recording ‘represents only one possible interpretation’ and the seriousness with which he approaches the work is tempered with a healthy measure of wit.Too much, on 18 CDs, to absorb in a month of Sundays, this box is an ideal dipper in which anyone can find curiosity, surprise and entertainment galore - from an early Music for Marcel Duchamp to a positively exhilarating 1989 meditation on the Beatles. Never have the musical depths of I Wanna Hold Your Hand been so brilliantly illuminated. Such a shame that John Lennon never lived to hear it.___Norman Lebrecht is a regular presenter on BBC Radio 3 and a contributor to the Wall Street Journal, Bloomberg and other publications. He has written 12 books about music, the most recent being Why Mahler? He hosts the blog Slipped Disc.