Relation to Atonal Music
Definition: The relationship between Messiaen's modes and atonal compositional practices, particularly the distinction between modal harmony (which can suggest tonal centers) and systematic atonality (which avoids tonal reference).
Messiaen's Treatment: Example 310 of Chapter XV ("le Mystère de la Sainte Trinité") demonstrates how Messiaen mixes his modes with atonal music. The principal melody, given to the intermediate voice, is written in the second mode of limited transpositions (third transposition for the first measure, first transposition afterwards). The upbeat and terminations of the upper voice, and the rhythmic pedal of the bass, are written in atonal style, creating a general sensation of the key of D.
Modern Context: The term "atonal" in 1944 carried different connotations than it might today. Messiaen likely refers to freely chromatic writing outside any modal or tonal system—passages using all twelve pitch classes without systematic organization. The example demonstrates that atonal elements can coexist with modal materials within a single texture, provided voice-leading and registral differentiation maintain clarity. The claim that this combination creates "general sensation of the key of D" reveals Messiaen's conviction that even in contexts mixing modal and chromatic materials, tonal orientation remains perceptible through strategic emphasis. Contemporary theory might describe this as "centric" rather than "tonal" music—music projecting a pitch center without employing functional harmony. The combination of modal melody with atonal accompaniment anticipates techniques in later twentieth-century music where composers layer materials from different harmonic systems to create complex textures. This approach differs fundamentally from the systematic atonality of the Second Viennese School (Schoenberg, Berg, Webern), where avoidance of tonal reference constitutes a primary compositional goal. Messiaen's practice remains more eclectic, employing atonal passages as coloristic resources rather than adhering to atonal principles systematically.
Examples: Example 310 (Chapter XV)