Abu Hamid al-Ghazali

Abu Hamid Muhammad al-Ghazali (450/1058–505/1111), known in Latin as Algazel, was a Persian Shafi'i jurist, Ash'ari theologian, and Sufi who became one of the most influential figures in classical Sunni Islam. Trained under al-Juwayni at the Nizamiyya of Nishapur, he was appointed by Nizam al-Mulk to the Nizamiyya of Baghdad in 484/1091, where he taught law and kalam before a personal and spiritual crisis (488/1095) led him to abandon his post for a decade of itinerant Sufi practice, recounted in al-Munqidh min al-dalal. His Tahafut al-falasifa systematically critiques twenty doctrines of the falasifa, especially al-Farabi and Ibn Sina, charging three—eternity of the world, denial of God's knowledge of particulars, and denial of bodily resurrection—with unbelief (kufr). The work also deploys an occasionalist critique of necessary causation later echoed by Hume. His Ihya' 'ulum al-din synthesizes jurisprudence, theology, and Sufi ethics, while al-Iqtisad fi al-i'tiqad articulates a moderate Ash'ari doctrine of God. Ibn Rushd's Tahafut al-tahafut is the most famous rebuttal; later critics such as Ibn Taymiyya faulted his philosophical concessions, while Ibn Tufayl questioned the consistency of his esoteric and exoteric writings. Ghazali's integration of kalam, falsafa-derived logic, and Sufism shaped subsequent Ash'arism and post-Avicennan philosophy across the Islamicate world.