Abu Jafar Muhammad Ibn Muhammad Ibn al-Hasan Nasir
al-Din al-Tusi is an Iranian Muslim, and was one of the greatest scientists,
philosophers, mathematicians, astronomers, theologians and physicians of the
7th/13th century Islamic lands and he was also a prolific writer. He was
born in Tus (Khurasan) in 597/1201 C.E. He learnt sciences and philosophy
from Kamal al-Din Ibn Yunus and others. He died in Baghdad in 672/1274.
His father was a jurist in the Twelfth Imam School. The school where al-Tusi
was educated was mainly a religious establishment. However, while studying
in Tus, he was taught other topics by his uncle, which had an important
influence on his intellectual development. These topics included logic,
physics and metaphysics. He also studied mathematics with other teachers, in
particular algebra and geometry.
His ability and talent in learning enabled him to master a number of
disciplines in a relatively short period, and he showed a great interest for
mathematics, astronomy and the intellectual sciences at a very young age.
At the age of twenty-two or a while later, Tusi joined the court of Nasir
al-Din Muhtashim, the Muslim governor of Quhistan, Northeast Iran, where he
was accepted into the Islamic community as a novice (mustajib).
A sign of close personal relationship with Muhtashim's family is to be seen
in the dedication of a number of his scholarly works such as Akhlaq-i Nasiri
and Akhlaq-i Muhtashimi to Nasir al-Din himself and Risala-yi Mu‘iniyya to
his son Mu‘in al-Din.
In 1256 when the Mongols conquered Almut, Nasir al-Din joined Hulegu's
service. Hulegu being himself interested in science, treated al-Tusi with
great respect and he was deeply impressed by his knowledge, including his
astrological competency; appointed him as one of his ministers, and, later
on, as administrator of Auqaf. He was instrumental in the establishment and
progress of the observatory at Maragha.
He made significant contributions in a large number of subjects, and it is
indeed difficult to present his work in a few words. He wrote one or several
treatises on different sciences and subjects including those on geometry,
algebra, arithmetic, trigonometry, medicine, metaphysics, logic, ethics and
theology. In addition he wrote poetry in Persian.
Being the chief scientist and the supervisor at the observatory established
at Maragha, he made significant contributions to astronomy. The observatory
was equipped with the best possible equipments, including those collected by
the Mongol armies from Baghdad and other Islamic centers. The instruments
included astrolabes, representations of constellations, epicycles, shapes of
He himself invented an instrument 'turquet' that contained two planes. After
the devoted work of 12 years at the observatory and with the assistance of
his group, he produced new astronomical tables called Al-Zij-Ilkhani
dedicated to Ilkhan (Hulegu Khan). Although Tusi had contemplated completing
the tables in 30 years, the time required for the completion of planetary
cycles, but he had to complete them in 12 years on orders from Hulegu Khan.
The tables were largely based on original observations, but also drew upon
the then existing knowledge on the subject. The Zij-Ilkhani became the most
popular tables among astronomers and remained so till the 15th century.
Nasir al-Din pointed out several serious shortcomings in Ptolemy's astronomy
and foreshadowed the later dissatisfaction with the system that culminated
in the Copernican reforms.
In mathematics, his major contribution would seem to be in trigonometry,
which was compiled by him as a new subject in its own right for the first
time. Also he developed the subject of spherical trigonometry, including six
fundamental formulas for the solution of spherical right-angled triangles.
In philosophy, his work on ethics entitled Akhlaq-i-Nasri became the most
important book on the subject, and remained popular for centuries. His book
Tajrid-al-'Aqaid was a major work on al-Kalam (Islamic Scholastic
Philosophy) and enjoyed widespread popularity. Several commentaries were
written on this book.
In logic al-Tusi followed the teachings of ibn Sina (Avicenna). He wrote
five works on the subject, the most important of which is one on inference.
He wrote a famous work on minerals, which contains an interesting theory of
colors based on mixtures of black and white, and included chapters on jewels
and perfumes. He also wrote on medicine, but his medical works are among his
The list of his known treatises is exhaustive; Brockelmann lists 56 and
Sarton 64. About one-fourth of these concern mathematics, another fourth
astronomy, another fourth philosophy and religion, and the remainder other
The books, though originally written in Arabic and Persian, were translated
into Latin and other European languages in the Middle Ages and several of
these have been printed.
Tusi's influence has been significant in the development of science, notably
in mathematics and astronomy. His books were widely consulted for centuries
and he has been held in high repute for his rich contributions. Tusi's fame
in his own lifetime guaranteed the survival of almost all of his scholarly
Syria like many other countries around the world
witnessed, during this period, the flood of refugees
from war troubled nations like Somalia, arrival of
people from Algeria during the brutal struggling between
the Mujahidun and the government, resettlement of the
Palestinians fleeing from sophisticated guns of the
Israelis as well as adventure of African migrants for