This is the first English translation of the last known philosophical work of the great eleventh-century Ismaili thinker, poet, and Fatimid emissary, Nāṣir-i Khusraw. Appointed from Cairo by command of the Fatimid Imam-caliph al-Mustanṣir to serve first as a dāʿī, and then as the ḥujjat, for the entire region of Khurasan, he maintained his allegiance to both his mission and his Imam for the rest of his life, even when threatened and driven into exile.

Written during his exile in Badakhshan in the year 1070 CE, Nāṣir-i Khusraw here develops a powerful presentation of both Aristotelian philosophy and Ismaili exegesis, or taʾwīl, and strives to show that they are ultimately in harmony. The work is presented as a learned commentary on a long philosophical poem, written in the previous century and sent to Nasir by the amīr of Badakhshan, ʿAl b. Asad, who copied the poem out in his own hand from memory and asked the poet-philosopher to explicate it.

In doing so, Nasir ranges over a huge span of topics from logic and language to the nature of the physical world, from the spheres of the highest heavens to the plants and animals of the earthly realm, and, most importantly, hidden spiritual realities: the esoteric (bāṭin) as well as the exoteric (ẓahir) realms. He thus discusses the nature of God, the creation of human beings, and the mysteries concealed in the physical world, itself a reflection of a higher, transcendent realm.

Between Reason and Revelation: Twin Wisdoms Reconciled is an annotated translation of the Persian text prepared by Henry Corbin and Mohammed Muʿin based on the single surviving manuscript of the work, now in the Süleymaniye Mosque Library in Istanbul. It is a work of great philosophical and spiritual insight, which is also a pioneering attempt to tackle difficult intellectual problems in the Persian language; it is at once lucid and lyrical, precise and speculative. Nasir’s influence has been immense as both a poet and a thinker, and the Kitāb-i Jāmiʿ al-Ḥikmatayn is his crowning work.