Naṣīr al-Dīn al-Ṭūsī (1201–1274) is a Shiʿa Iranian author of some two hundred treatises in a number of disciplines, including philosophy, mathematics, astronomy, mysticism, and theology.

Life and Times

Naṣīr al-Dīn was born in the city of Tus in the province of Khurasan in northwestern Iran, the first area to be devastated by the Mongolian invasion of the Middle East by Helagu Khan (1217–1265), grandson of Genghis Khan (1167?–1227). After completing his formal studies, al-Ṭūsī carried out research and publications under the patronage of various Ismaili rulers from 1227 until 1256, when he assisted the Ismaili ruler to surrender to Helegu Khan, who employed al-Ṭūsī as his...