John Cage (1912-1992), the American avant-garde composer, is considered one of the twentieth century's most important innovators of experimental music. In 1930s New York, he studied world music with Henry Cowell and composition with Adolph Weiss. Cage then spent two years studying in California with Schönberg, who later said he was the only one of his American students that interested him. Cage became fascinated by modern dance and accompanied dance classes in Los Angeles and Seattle, where he met his future life partner Merce Cunningham. In his compositions, rhythm and timbre became increasingly important, and in 1940 he invented the 'prepared piano': he inserted various objects between the strings of a grand piano resulting in a wide variety of timbres and, in Cage’s words, created “a percussion orchestra under the control of a single player.” One of his major works for this instrument, Sonatas and interludes for prepared piano (1946-1948) is a milestone in 20th century piano music. In 1951, he was presented with a copy of the I Ching, or the Book of Changes, a Classical Chinese tome on divination. For Cage, the I Ching became the means to compose music using chance operations and indeterminacy in his compositions. One of the earliest results of this new method was Music of Changes for solo piano in 1951. The following year he wrote the infamous 4'33", a work in which the performer is instructed to remain silent during the prescribed time; the sounds of the environment are all that can be heard. He also wrote a number of the earliest electro-acoustic compositions in this period. Cage's fame started to grow from the 1960s onwards. In the 1980s, Cage, whose chance-composed music had almost always had a theatrical quality, started focusing on opera, ultimately completing a series of five Europeras. Cage died on 12 August 1992. In 2012 the Holland Festival, which has performed many of Cage's works over the years, organised a celebration marking the centenary of his birth. Founded in 2003 and based in The Hague, Ensemble Klang is focused on both the new generation of composers – such as Peter Adriaansz, Kate Moore, Andrew Hamilton, Matthew Wright and Roi Nachson – and more established names such as Heiner Goebbels, Martijn Padding and Louis Andriessen.