Naṣīr al-Dīn Muḥammad ibn Muḥammad al-Ṭūsī was born in 1201 in Ṭūs, in Khorasan, within a family of Twelver Shīʿite allegiance. Philosopher, theologian, and author of about 150 works, he was considered a “third master,” after Aristotle and al-Fārābī. He was educated in Ṭūs and then he completed his education in Nīshāpūr, a highly reputed cultural center of his times, in Iraq and in Mosul. His studies included Arabic, logic, metaphysics, mathematics, medicine, law, religion, and natural sciences. Because of the Mongol invasion, he took refuge in Qūhistān’s fortresses, under the protection of the governor Naṣīr al-Dīn Muḥtashim. He then rapidly converted to the Ismāʿīlī faith and completed his main philosophical treatises, among which was his commentary to Avicenna’s Ishārāt.
After Alamūt’s fall, Ṭūsī became vizier of Hūlāġū, the Mongol commander. Thanks to Hūlāġū’s patronage, Ṭūsī established in Maragha the largest astronomical observatory of the times. He died in Baghdad in 1274 and was buried next to the seventh Shīʿite Imam in a site near the city.
Naṣīr al-Dīn al-Ṭūsī is considered one of the most important figures of Islamic thinking. He was one of the most prolific scholars of the thirteenth century, and left his mark on most literary and scientific disciplines.