From an early age, Busoni was an outstanding if sometimes controversial pianist. He studied at the Vienna Conservatory and then with Wilhelm Mayer and Carl Reinecke. After brief periods teaching in Helsinki, Boston, and Moscow, he devoted himself to composing, teaching, and touring as a virtuoso pianist in Europe and the United States. His writings on music were influential, and covered not only aesthetics but considerations of microtones and other innovative topics. He was based in Berlin from 1894 but spent much of World War I in Switzerland.