<P> Nevertheless, an incisive critique of vanguardism as against the views of mainstream society was offered by the New York critic Harold Rosenberg in the late 1960s . Trying to strike a balance between the insights of Renato Poggioli and the claims of Clement Greenberg, Rosenberg suggested that from the mid-1960s onward progressive culture ceased to fulfill its former adversarial role . Since then it has been flanked by what he called "avant - garde ghosts to the one side, and a changing mass culture on the other", both of which it interacts with to varying degrees . This has seen culture become, in his words, "a profession one of whose aspects is the pretense of overthrowing it". </P> <P> Avant - garde in music can refer to any form of music working within traditional structures while seeking to breach boundaries in some manner . The term is used loosely to describe the work of any musicians who radically depart from tradition altogether . By this definition, some avant - garde composers of the 20th century include Arnold Schoenberg, Charles Ives, Igor Stravinsky, Anton Webern, George Antheil (in his earliest works only), Alban Berg, Henry Cowell (in his earliest works), Philip Glass, Harry Partch, John Cage, Morton Feldman, Richard Strauss (in his earliest work), Karlheinz Stockhausen, Edgard Varèse, and Iannis Xenakis . Although most avant - garde composers have been men, this is not exclusively the case . Women avant - gardists include Pauline Oliveros, Diamanda Galás, Meredith Monk, and Laurie Anderson . </P> <P> There is another definition of "Avant - gardism" that distinguishes it from "modernism": Peter Bürger, for example, says avant - gardism rejects the "institution of art" and challenges social and artistic values, and so necessarily involves political, social, and cultural factors . According to the composer and musicologist Larry Sitsky, modernist composers from the early 20th century who do not qualify as avant - gardists include Arnold Schoenberg, Anton Webern, and Igor Stravinsky; later modernist composers who do not fall into the category of avant - gardists include Elliott Carter, Milton Babbitt, György Ligeti, Witold Lutosławski, and Luciano Berio, since "their modernism was not conceived for the purpose of goading an audience ." </P> <P> Whereas the avant - garde has a significant history in 20th - century music, it is more pronounced in theatre and performance art, and often in conjunction with music and sound design innovations, as well as developments in visual media design . There are movements in theatre history that are characterized by their contributions to the avant - garde traditions in both the United States and Europe . Among these are Fluxus, Happenings, and Neo-Dada . </P>

Exponent of avant garde artistic movement 20th century