Fakhr al-Din al-Razi

Fakhr al-Din al-Razi (also called Ibn al-Khatib) was a Persian scholar born in Rayy, near present-day Tehran, in 1149 CE (544 AH). His father, a preacher of Rayy, was his first teacher and stood in a chain of students reaching back to the influential Ash'ari theologian al-Juwayni. (Ash'arism is one of the main schools of Sunni speculative theology, called kalam.) After early studies in Nishapur and at Maragha, al-Razi spent much of his life traveling across Persia and Central Asia in search of patrons, students, and worthy opponents to debate.

He is remembered above all for his enormous Qur'an commentary, the Mafatih al-Ghayb ("Keys to the Unseen," also called al-Tafsir al-Kabir), and for theological summas such as the Muhassal. A defining feature of his thought was his deep, critical engagement with the philosophy of Ibn Sina (Avicenna): he absorbed its tools while contesting many of its conclusions. Scholars regard him as a pivotal figure in what is sometimes called "post-classical" Islamic thought.

His many recorded debates—against Mu'tazili, Maturidi, Hanbali, and other thinkers—are partly preserved in his own account of his disputations in Transoxania. He enjoyed patronage from the Khwarazm-Shahs and, later, the Ghurid sultans. He died in Herat in 1210 CE (606 AH). His precise philosophical positions, which appear to shift across his career, remain debated among specialists.