Sa‘īd b. Dādhurmuz is an eleventh century Iranian intellectual whose writings exhibit a combination of the three main theoretical disciplines in Islamic thought, theology (Kalām), philosophy (Falsafa) and mysticism (Tasawwuf). Sa‘īd b. Dādhurmuz’s oeuvre exhibits a syncretic philosophy, which makes the most of the humanist atmosphere of his age. Although he draws on many authorities from contemporary and past Muslim philosophers and theologians, the most characteristic motif of his writing is his use and adaptation of the Epistles of the Brethren of Purity (Ikhwān al-Ṣafā). Sa‘īd b. Dādhurmuz’s epistles, On the Superiority of the Hereafter over the World, On Soul and Spirit, and On Unity, is a unique project that retains the philosophical tradition in the Islamic world in an age in which Ghazālī’s The Incoherence of Philosophers initiates an epistemic changeover for centuries to come.