D’Indy taught him. He met Debussy while working as a café pianist; a long friendship eventually ended by a misunderstanding. Ravel met him as a student. He told Poulenc, rejected by the Conservatoire and accused of being a disciple, to laugh it off. He collaborated with Picasso, Diaghilev, Massine and Cocteau, with Picabia and Clair, and wrote about his friend Stravinsky’s music. Valadon was briefly his lover, Thomson saw him as his mentor, and Ray’s first readymade was jointly contrived the day they met. Milhaud helped sort through his belongings (25 years’ worth in one room) after his death.