Music-theoretical discourse on musical form has been dominated in recent decades by schema-based approaches—most prominently William Caplin's theory of formal functions and the sonata theory of Hepokoski and Darcy—which privilege the identification of discrete, normative formal units over the listener’s experience of music as a continuous temporal unfolding. While analytically powerful, these frameworks tend to bracket the subjective, perceptual dimension of form, treating it as a structural object rather than a heard process.

This paper recovers the work of the German music theorist Kurt Westphal (1904–1986) as a neglected but remarkably productive alternative. In his 1935 monograph Der Begriff der musikalischen Form in der Wiener Klassik, Westphal develops the concept of the Verlaufskurve, a “progression/process curve” that models musical form not as a taxonomy of schemas but as a dynamic, directed process of tension and resolution apprehended by a listening subject. Drawing on the phenomenological tradition of Edmund Husserl and the Gestalt-psychological insights of Christian von Ehrenfels, Westphal insists that form is irreducibly temporal: it is constituted in the act of hearing, not imposed upon the music from without.

By situating Westphal within his intellectual context—including his engagement with August Halm, Ernst Kurth, and Hans Mersmann—and by tracing the implications of the Verlaufskurve for contemporary form theory, this paper argues that a phenomenologically grounded concept of musical form offers a productive corrective to the abstracting tendencies of current analytical practice, and that Westphal’s largely forgotten contribution deserves renewed attention in both music theory and the broader study of musical perception.