High Quality Content by WIKIPEDIA articles! Sonatas and Interludes is a collection of twenty pieces for prepared piano by American avant-garde composer John Cage (1912–1992). It was composed in 1946–1948, shortly after Cage`s introduction to Indian philosophy and the teachings of art historian Ananda K. Coomaraswamy, both of which became major influences on the composer`s later work. Significantly more complex than his other works for prepared piano,Sonatas and Interludes is generally recognized as one of Cage`s finest achievements.