Nasir al-Tusi – A major intellectual Muslim scholar of the thirteenth century

Born in Tus (close to Mashhad) in Iran in 1201. His ability and talent in learning enabled al-Tusi to master a number of disciplines in a relatively short period. In 1236, the renowned astronomer and mathematician went to Alamut, the centre of Nizari Ismaili government, where he used its rich library to write some of his most important scientific works.

Tusi also made important contributions to the Nizari Ismaili thought of the period as expressed in his Rawda-yi taslim, published recently by The Institute of Ismaili Studies together with an English translation under the title of Paradise of Submission. Al-Tusi also established the most sophisticated observatory of his time at Maragha in Iran and made significant contributions to the development of the heliocentric model of the planetary system.

One of his works titled al-Tadhkirah fi ‘ilm al-hay’a (Memoir on the Science of Astronomy) had an enormous influence on the subsequent history of astronomy, both in and beyond the borders of Islam. He also created trigonometry as an independent branch of pure mathematics rather than just as a tool for astronomical applications.

From Ibn Sina to Tusi: The Scientific Tradition in Medieval Islam
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