Widely considered to be an art today, music in the medieval Islamic world was categorized as a branch of the mathematical sciences; in fact, some philosophers and scholars of music went as far as linking music with medicine and astrology as part of an interconnected web of cosmological knowledge. Focusing on the science of music this book discusses how a non-European premodern intellectual tradition – in this case, the Islamic philosophical tradition – conceptualized science. Furthermore, it explores how this intellectual tradition produced “correct” scientific statements and how it envisioned science’s relationship with other bodies of knowledge. Finally, it investigates what made music a science in the medieval Islamic world by examining the ontological debates surrounding the nature of music as a scientific discipline as well as the epistemological tools and techniques that contributed to the production of musical knowledge during the medieval period (third/ninth–ninth/fifteenth centuries).