28. The Life and Legacy of Nasir al-Din al-Tusi

Nasir al-Din al-Tusi (1201–1274) was one of the most influential scholars of the Islamic Golden Age, whose contributions spanned astronomy, mathematics, philosophy, theology, and ethics. Living during a tumultuous period marked by the Mongol invasions, al-Tusi not only survived but thrived, leaving an indelible mark on the intellectual history of the world. This podcast explores his life, major works, and enduring legacy, highlighting his role as a bridge between classical antiquity and the Renaissance.

Timeline of Main Events

1201: Nasir al-Din al-Tusi is born in Tus, Khorasan (modern-day Iran), on February 18th.

Early Life: Tusi studies various subjects including mathematics, logic, physics, and metaphysics in Tus, his father is a jurist in the Twelver Imam school.

~1214: Genghis Khan and the Mongols begin their westward expansion.

~1220: The Mongol invasion reaches the area of Tus causing much destruction.

~1223-1224: Tusi becomes dissatisfied with his current knowledge and begins exploring Ismaili thought. He converts to Ismailism and joins the service of Nasir al-Din Muhtashim in Quhistan, and becomes a novice (mustajib).

1232: Tusi writes Akhlaq-i Nasiri, a work on ethics, dedicated to Nasir ad-Din 'Abd ar-Rahim.

~1235: Tusi completes Akhlaq-i Nasiri.

~1236: Tusi arrives at Alamut, the center of the Nizari Ismaili state, and becomes a member of the Ismaili court. He takes on an elevated position in the Ismaili da’wa, possibly ascending to the position of chief missionary.

1236-1256: Tusi spends approximately 20 years at Alamut, teaching, editing, writing, and compiling scholarly works on mathematics, philosophy, astronomy, and more.

1247: Tusi writes Tahrir al-Majisti (Commentary on the Almagest).

1256: Hulegu Khan, a grandson of Genghis Khan, leads the Mongol forces in the attack of Alamut. The castle falls and is destroyed. Tusi joins the Mongol forces under Hulegu, possibly feeling held against his will in Alamut previously.

1258: The Mongol forces under Hulegu attack and capture Baghdad. Al-Musta'sim, the Abbasid caliph, is killed, and the city is plundered and burned.

1259: Construction of the Maragheh Observatory begins under the guidance of Tusi at Hulegu's request.

1262: The Maragheh Observatory becomes operational.

~1262-1274: Tusi leads the work at the Maragheh Observatory, produces the Zij-i Ilkhani, and makes significant advances in astronomy and mathematics, including the development of the Tusi-couple.

1265: Tusi writes a manuscript concerning the calculation of n-th roots.

1274: Tusi dies in Baghdad on June 26th (18 Dhu’l Hijja 672).