One thought-provoking passage from the introductory wall panel at the entrance to Los Angeles’s Museum of Contemporary Art’s recent exhibition, Visual Music: Synaesthesia in Art and Music Since 1900, read as follows: “Music offered a model to which art might aspire: an art based on a language of abstract form that evokes limitless space and evolving time, in short, ‘visual music.’” This brief passage makes some challenging and complex claims for the broad category of visual art as it relates to the equally broad category of music. One clear precedent for these claims can be found in the writing of one of the twentieth century’s most influential critics. In his seminal essay “Avant-Garde and Kitsch” (1939), Clement Greenberg declared that to retain its relevance in contemporary culture avant-garde production—specifically painting—must, “imitate God by creating something valid, solely on its own terms . . . something given, increate, independent of meanings, similars or originals . . . [something that] cannot be reduced in whole or in part to anything not itself” (Clement Greenberg, “Avant-Garde and Kitsch,” in Art and Culture: Critical Essays, Boston: Beacon Press, 1961; 6 [emphasis in original]). Interestingly, Greenberg felt that of all the arts the one most...