In his unfinished work The Rational and Social Foundations of Music, Max Weber considers the history of western music from the viewpoint of rationalization. It is uncommon to think of art and music using the concept of rationalization. Weber's analysis concentrates on the detailed historical process of the construction of modern musical tone systems (well-tempered systems and the equal temperament). However he does not explain why the viewpoint of rationalization is meaningful to understand the history of western music and modern society; therefore his study of music has been regarded as musicological, not sociological.
　This paper seeks to reveal the meaning of rationalization in the history of western music, especially in the modern era, through the relations between rationalization and the body.
　Since ancient Greece, the emotional and passionate side of music, that is, the Dionysian character of music has been much discussed, because it has been thought to have a great influence upon human character {ethos). In medieval Christianity a certain kind of instrumental music was prohibited and the central genre of music was a vocal music that was regarded as rational and religious, because it depended on words and texts (logos). But after the Baroque era, the instrumental music made rapid progress as music was gradually established as an autonomous Art, and it raised a serious problem about the status of music. The instrumental music, which is 'music without words,' does not have a clear meaning and message, so it was despised as useless entertainment and the music's status of Art was suspected and criticized. To overthrow this criticism and to guard its status of an art, music was rationalized in various respects by repressing the emotional and corporeal elements of tone system, music form and musical experiences.
　Weber's abstract and musicological analysis of the tone systems can be situated in this context of musical rationalization directed at establishing an autonomous field of Music in the art and aesthetics of the modern era.