Contagion, Causality, Critique: A Late-Mamluk Digest of Natural Science “Powers Impossible to Alter”: the Influence of Māturīdī Theology over Rāghib al-Iṣfahānī’s Concept of Natural Endowment “How Great a Teacher is the Night!” Sleeplessness in Medieval Islamic Scholarly Culture Innate Heat and Human Sexuality in a Fifteenth-Century Digest of Natural Philosophy