African American musicians in the 1950s faced a dilemma regarding classical music. A cosmopolitan display of knowledge about modern classical music enabled artists such as Duke Ellington to counter misconceptions that jazz musicians were untutored. Yet jazz musicians' interest in classical music was often taken as an admission that jazz innovations were derived from European sources. After Charlie Parker expressed admiration for Bartok, an interviewer asked if Parker's musical innovations were adaptations of classical predecessors ideas. Often, comparisons with modem European composers connected jazz to the presumed superior standards of classical music without recognizing that jazz articulated its own musical vision—by developing expressive and improvisational principles rooted in a wide variety of African American musics—that challenged the hegemony of European standard in American music.