The writings of theologians Thierry of Chartres (d. 1157) and Nicholas of Cusa (d. 1464) represent a lost history of momentous encounters between Christianity and Pythagorean ideas before the Renaissance. Their robust Christian Neopythagoreanism reconceived the Trinity and the Incarnation within the framework of Greek number theory, challenging our contemporary assumptions about the relation of religion and modern science.David Albertson surveys the slow formation of theologies of the divine One from the Old Academy through ancient Neoplatonism into the Middle Ages. Against this backdrop, Thierry of Chartres's writings stand out as the first authentic retrieval of Neopythagoreanism within western Christianity. By reading Boethius and Augustine against the grain, Thierry reactivated a suppressed potential in ancient Christian traditions that harmonized the divine Word with notions of divine Number.Despite achieving fame during his lifetime, Thierry's ideas remained well outside the medieval mainstream. Three centuries later Nicholas of Cusa rediscovered anonymous fragments of Thierry and his medieval readers, and drew on them liberally in his early works. Yet tensions among this collection of sources forced Cusanus to reconcile their competing understandings of Word and Number. Over several decades Nicholas eventually learned how to articulate traditional Christian doctrines within a fully mathematized cosmology-anticipating the situation of modern Christian thought after the seventeenth century.Mathematical Theologies skillfully guides readers through the newest scholarship on Pythagoreanism, the school of Chartres, and Cusanus, while revising some of the categories that have separated those fields in the past.

AcknowledgmentsAbbreviationsIntroduction: Toward a Genealogy of Christian NeopythagoreanismPART ONE: The Genesis of Neopythagoreanism: A Synopsis1. Platonic Transformations of Early Pythagorean PhilosophyMathematics as Philosophy in Philolaus and ArchytasMathematics as Mediation in PlatoMediation and First Philosophy in the Early Academy2. The Neopythagorean Revival: Henology and MediationThe Origins of Henology in Eudorus and ModeratusHenology on the Margins of Middle PlatonismMathematical Theology in Nicomachus of Gerasa3. The Late Antique Preservation of NeopythagoreanismIamblichus, Proclus, and the Legacy of NicomachusAugustine and the Number without numberBoethius and the Fate of the QuadriviumPART TWO: The Pearl Diver: Thierry of Chartres's Theology of the Quadrivium4. Thierry's Trinitarian Theology in ContextThe Status of Mediation in Twelfth-Century PlatonismThe Problem of Bernard's GlossThierry on Quadrivium and Trinity5. The Discovery of the FoldAttempts at a Universal Theory of ScienceThe Achievement of the Modal TheoryThierry as Neopythagorean Theologian6. Thierry's Diminished LegacyConfusion about MediationAn Augustinian CensorA Late-Medieval Refutation: Word or Number?PART THREE: Bright Nearness: Nicholas of Cusa's Mathematical Theology7. The Accidental Triumph of De docta ignorantiaA Patchwork of Conflicting SourcesExperiments in Chartrian TheologyThe Christological Double Synthesis8. Chartrian Theology on Probation in the 1440sAn Agenda for the 1440s in Two SermonsThe Neopythagorean CounterexperimentTwo Paradigms of Mediation9. The Advent of Theologia geometrica in the 1450sThe Restoration of Thierry's Modal TheoryA New Foundation for Mathematical TheologyThe Word as Number and Angle10. Completing the Circle in the 1460sNew Impulses in the Late WorksIncarnation and NeopythagoreanismFigurae mundiEpilogueNotesBibliography