This study engages a network of music, myth, and metaphysics within late-ancient and twelfth-century music theory and cosmology. It traces the development, expansion, and demise of a (natural-)philosophical harmonic speculation that stems largely from an a priori commitment to a harmonic cosmology with its deepest roots in Plato’s Timaeus. It argues that music theory not only allowed twelfth-century thinkers to conceptualize the fabric of the universe, but it also provided a hermeneutic tool for interpreting the ancient and late-ancient texts that offered detailed theories of the world’s construction. The twin goals of this study are thus philosophical and musicological: firstly and philosophically, to analyze and re-assert the importance of musical speculation in the writings of the self-styled physici, who probed the physical world and its metaphysical foundations during the ‘Twelfth-Century Renaissance’; secondly and musicologically, to document the sources and scope of this musical speculation and to situate it within the larger tradition of ‘speculative music theory.’ The first part of the thesis (chapters one and two) disentangles the knotty question of sources for and connections between the late-ancient texts (by Calcidius, Macrobius, and Boethius) that form the background of twelfth-century thought, and it sketches the proper domain of musical thought by tracing the expansion of music’s role in quadrivial and natural-philosophical contexts from late-ancient encyclopedism though various twelfth-century divisiones scientiae. The second part of the thesis (chapters three through five) assembles and analyzes the direct evidence for twelfth-century harmonic theory. These chapters, heuristically organized around the Boethian tripartition of music, present an anagogic ascent per aspera ad astra. Chapter three (musica instrumentalis) highlights the occasional and perhaps surprising employ of practical, technical music theory in cosmological contexts, and focuses on the epistemological foundations of hearing and the ontological status granted to the sonorous ‘objects’ of hearing. Chapter four (musica humana) targets the anthropological, psychological, and ethical implications of musical relations in and between body and soul. Finally, chapter five (musica mundana) outlines the cosmological framework, the anima mundi in particular, that underpins the concordant machinations of the machina mundi in all its manifestations.

This study engages a network of music, myth, and metaphysics within late-ancient and twelfth-century music theory and cosmology. It traces the development, expansion, and demise of a (natural-)philosophical harmonic speculation that stems largely from an a priori commitment to a harmonic cosmology with its deepest roots in Plato’s Timaeus. It argues that music theory not only allowed twelfth-century thinkers to conceptualize the fabric of the universe, but it also provided a hermeneutic tool for interpreting the ancient and late-ancient texts that offered detailed theories of the world’s construction. The twin goals of this study are thus philosophical and musicological: firstly and philosophically, to analyze and re-assert the importance of musical speculation in the writings of the self-styled physici, who probed the physical world and its metaphysical foundations during the ‘Twelfth-Century Renaissance’; secondly and musicologically, to document the sources and scope of this musical speculation and to situate it within the larger tradition of ‘speculative music theory.’ The first part of the thesis (chapters one and two) disentangles the knotty question of sources for and connections between the late-ancient texts (by Calcidius, Macrobius, and Boethius) that form the background of twelfth-century thought, and it sketches the proper domain of musical thought by tracing the expansion of music’s role in quadrivial and natural-philosophical contexts from late-ancient encyclopedism though various twelfth-century divisiones scientiae. The second part of the thesis (chapters three through five) assembles and analyzes the direct evidence for twelfth-century harmonic theory. These chapters, heuristically organized around the Boethian tripartition of music, present an anagogic ascent per aspera ad astra. Chapter three (musica instrumentalis) highlights the occasional and perhaps surprising employ of practical, technical music theory in cosmological contexts, and focuses on the epistemological foundations of hearing and the ontological status granted to the sonorous ‘objects’ of hearing. Chapter four (musica humana) targets the anthropological, psychological, and ethical implications of musical relations in and between body and soul. Finally, chapter five (musica mundana) outlines the cosmological framework, the anima mundi in particular, that underpins the concordant machinations of the machina mundi in all its manifestations.

Music theory of Hildegard of Bingen’s era articulated a cosmological worldview, providing thinkers with a way of understanding human beings, the world, the heavens, and how they all interact with each other in musical terms. Hildegard was familiar with this music theory through her theological predecessors. This dissertation argues that a better understanding of Hildegard’s theology requires a deeper consideration of how this musical cosmology influenced her because of the way music pervades her work. Music theory is a major piece of what undergirds her Benedictine, liturgical worldview. To demonstrate this, I take up the task of explicating and illuminating Hildegard’s Christology in terms of her understanding of music and music theory. This task is different from previous scholarship which analyzes Hildegard’s writing about music in terms of her broader theology. I bridge the gap between musicologists and liturgists, on the one hand, who focus on Hildegard’s theology of music but neglect broader consideration of her theology and, on the other hand, theologians who acknowledge music as an integral part of Hildegard’s life but largely consider her theological visions in abstraction from it. I argue that Hildegard uses music theory to define and explicate Christ and Christ’s interactions with the world, sometimes explicitly, but primarily implicitly. Her theological vision centers Christ in a resounding universe. By understanding Christ as symphonia, Hildegard emphasizes the Son’s unique relationship with humanity. While readers cannot understand every aspect of Hildegard’s Christology by considering music theory, music theory helps to illuminate it in a particular way, enabling us to understand Hildegard’s theology more deeply. Thus, this study provides an example for how future scholars can continue to interpret Hildegard’s understanding of various theological loci. In addition, it submits Hildegard as an example of how to unite music/liturgy and theology in a fruitful way for both the Academy and the Church. / 2025-04-25T00:00:00Z