Summary

Chapter XII concludes the melodic section by demonstrating how Messiaen's innovations operate within large-scale formal structures, addressing both traditional instrumental forms (fugue, sonata-allegro) and plainchant liturgical genres (anthem, alleluia, psalmody, Kyrie, sequence). By identifying recapitulation as obsolete and emphasizing terminal development as essential, Messiaen reveals his preference for teleological forms building toward climactic arrivals rather than symmetrical returns. The extensive treatment of plainchant forms reflects his Catholic faith and organist background—these liturgical structures provide formal models embodying centuries of sacred practice while accommodating his modal-rhythmic innovations. Through detailed analyses of movements from his major works, Messiaen demonstrates that complete pieces organize melodic materials (derived from diverse sources, developed through systematic transformations) within sentence structures (from Chapter XI) to create large-scale forms serving both structural coherence and spiritual expression. The chapter reveals Messiaen's synthetic method at maximum complexity: developmental procedures from Beethoven + canonic techniques from Bach + formal archetypes from plainchant + modes of limited transposition + Hindu rhythms + bird style + characteristic chords = personal language simultaneously historical and innovative, systematic and expressive, technical and theological.

For contemporary readers, this chapter illustrates how modernist innovations can function within traditional formal frameworks rather than requiring revolutionary formal approaches, and how composers can draw formal models from liturgical as well as instrumental traditions. Messiaen's forms are neither abstract structures nor programmatic narratives but rather embodiments of theological meanings—the Incarnation (descent of element B in "Dieu parmi nous"), Resurrection (jubilatory alleluia), Trinity (nine invocations, tripartite Kyrie), Word made flesh (sequence combining major tonality, plainchant mode, and Mode 2). This integration of technical innovation, formal tradition, and spiritual purpose completes the melodic section, preparing for the harmonic chapters (XIII–XIX) that will develop the modal and chordal language supporting these melodic-formal structures.