Presents an original theory of modality in the chorales of Johann Sebastian Bach, entailing an analytic methodology and individual analytic readings for chorales based on modal cantus firmi. Discusses the modal final as a generative and as a unifying tonic, and Bach's Phrygian, Mixolydian, Dorian, and Aeolian chorales and their harmonizations of cantus firmi. Appendices explore modal cadence systems in historical theory and cantus firmi as classified by 17th and 18th century theorists. Annotation copyright Book News, Inc. Portland, Or.