Islamic philosophy, known in Arabic as falsafa, is the tradition of rational inquiry that took up ancient Greek philosophy, above all Aristotle and Neoplatonism, and developed it in Arabic across the medieval Islamic world. Pursued by Muslim, Christian, and Jewish thinkers from roughly the ninth century onward, it produced original systems of metaphysics and logic and, through Latin translations, carried much of Greek thought back into Europe.
For centuries, Muslim philosophers pored over a book they treasured as the Theology of Aristotle, mining it for the master's deepest thoughts about God and the soul. Aristotle never wrote it. It was a reworking of a very different Greek thinker, Plotinus, who lived some five hundred years later and saw the universe streaming outward from a single divine source. The mistake was not a footnote. It quietly shaped how an entire tradition imagined the cosmos, binding Aristotle's cool logic to a mystical vision he would not have recognized.