No longer interested in simply developing his own version of the extreme chromaticism
and microtonality associated with Coltrane, Sanders and Ayler, he started to analyze the basic intervals that make up jazz and to re-examine their role in his improvisation, in search of a musical language that was still profound and expressive but also more straightforward.
Instead, he begins with the fact that Anglo- American literary modernists tended to be ill-informed about chromaticism
, serialism, and twentieth-century art music more generally.
Sure, acclaimed young composer-lyricist Adam Guettel and American Theatre's probing interviewer David Savran talk with great sophistication (in our lead feature, page 26) about what makes Guettel's score for the new musical The Light in the Piazza so special--its dramatic use of tension and release, its richly expressive chromaticism
, its debt to classical and contemporary influences.
This strategy measures "degrees of deviance" along a chromatic slide, and this graded chromaticism
seems to be based on a measure of mimetic efficacy.
"Joy" implied one kind of expression as opposed to another for "sorrow." It became customary to employ swifter rhythms, running figures, and diatonicism for joy, and slower rhythms, longer note values, and chromaticism
The Random House Dictionary seems pretty sound, if a bit stuffy, on the subject, suggesting that after originating in New Orleans at the beginning of the twentieth century it developed "through various increasingly complex styles, generally marked by intricate, melodic freedom, and a harmonic idiom ranging from simple diatonicism through chromaticism
to, in recent developments, atonality."
It is very close to a counterpoint in which potential modal centers have no identity and the chromaticism
is pervasive--a practice very similar to Charles Seeger's "dissonant counterpoint." 
He sensed his mission as the bringer of a salvational musical system that would lead harmonic usage out of the dead end of tonality vitiated by excessive chromaticism
. Schoenberg's twelve-tone expansion of musical language was one that was taken up by his "disciples" Anton Webern and Alban Berg, with varying degrees of rigor, at times with a language veering toward tonality (Berg), in other instances an even greater musical economy and manipulation of silence (Webern).
Indeed, after the chromaticism
, octatonicism, symmetries and experimentation with pitch, mode, texture and timbre of works such as Machines agricoles of 1919 (p.
The preceding passage (bars 425-32) is exceptionally striking in its use of the highly chromatic musical figure passus diriusculus, particularly as the piece is almost devoid of chromaticism
until this point.
Neither is it only a matter of the revolutionary chromaticism
that Wagner ventured, driving tonality to its limit (as in the much-discussed "Tristan Chord"), nor of his consequent influence on the theoretical developments definitive of the second Viennese school, without which twentieth-century music is unthinkable.