 This is not to suggest that the popularity enjoyed by artistic formalism during the late 19th and early 20th centuries owed mainly to its inference from the immediacy or disinterest theses. The most influential advocates of formalism during this period were professional critics, and their formalism derived, at least in part, from the artistic developments with which they were concerned. As a critic Eduard Hanslick advocated for the pure music of Mozart, Beethoven, Schumann, and later Brahms, and against the dramatically impure music of Wagner; as a theorist he urged that music has no content but “tonally moving forms” (Hanslick 1986, 29). As a critic Clive Bell was an early champion of the post-Impressionists, especially Cezanne; as a theorist he maintained that the formal properties of painting—“relations and combinations of lines and colours”—alone have artistic relevance (Bell 1958, 17–18). As a critic Clement Greenberg was abstract expressionism’s ablest defender; as a theorist he held painting’s “proper area of competence” to be exhausted by flatness, pigment, and shape (Greenberg 1986, 86–87).