牧神の午後への前奏曲
Bernstein indicates that the phonological transformation, or the extreme chromaticism of "Tristan", is at a breaking point for tonality, so part 3 examines the next step in twentieth-century ambiguity: atonality. Bernstein begins the foray into atonality with Debussy's "Prélude à l'après-midi d'un faune". This work uses a whole-tone scale, which is atonal but entails sufficient unambiguous containment, according to Bernstein.