Mafatih al-Ghayb (The Keys to the Unseen), also known as al-Tafsir al-Kabir, by Muhammad b. Fakhr al-Din al-Razi (d. 606 AH / 1210 CE) is one of the most intellectually ambitious works in the entire Islamic scholarly tradition, running to 32 volumes in standard print. Its primary objective is to demonstrate the rational coherence and theological depth of the Quran by applying the full resources of Ashari kalam, Islamic philosophy, classical logic, and natural science to Quranic exegesis, while systematically refuting deviant theological positions, especially Mutazilism. The manhaj is tafsir bi-al-rai at its most expansive: al-Razi treats each verse as an occasion for extended theological and philosophical inquiry, often ranging far beyond the immediate text into extended discussions of natural philosophy, medicine, cosmology, and formal argumentation. The classical observation that 'it contains everything except tafsir' reflects both the breadth and the criticism of this approach. al-Razi was among the greatest representatives of Ashari kalam and a polymath of extraordinary range. He is Shafii in fiqh and rigorously Ashari in aqidah. The work is indispensable for advanced scholars of theology, Islamic philosophy, and Quranic studies, though its length and complexity make it unsuitable for introductory or popular use. More...