Thabit
Ibn Qurra Ibn Marwan al-Sabi al-Harrani was born in the year 836
C.E. at Harran (present Turkey). As the name indicates he was
basically a member of the Sabian sect, but the great Muslim
mathematician Muhammad Ibn Musa Ibn Shakir, impressed by his
knowledge of languages, and realising his potential for a
scientific career, selected him to join the scientific group at
Baghdad that was being patronised by the Abbasid Caliphs. There,
he studied under the famous Banu Musa brothers. It was in this
setting that Thabit contributed to several branches of science,
notably mathematics, astronomy and mechanics, in addition to
translating a large number of works from Greek to Arabic. Later,
he was patronised by the Abbasid Caliph al-M'utadid. After a
long career of scholarship, Thabit died at Baghdad in 901 C.E.
Thabit's major contribution lies in mathematics and
astronomy. He was instrumental in extending the concept of
traditional geometry to geometrical algebra and proposed several
theories that led to the development of non-Euclidean geometry,
spherical trigonometry, integral calculus and real numbers. He
criticised a number of theorems of Euclid's elements and
proposed important improvements. He applied arithmetical
terminology to geometrical quantities, and studied several
aspects of conic sections, notably those of parabola and
ellipse. A number of his computations aimed at determining the
surfaces and volumes of different types of bodies and
constitute, in fact, the processes of integral calculus, as
developed later.
In astronomy he was one of the early reformers of Ptolemic
views. He analysed several. problems related to the movements of
sun and moon and wrote treatises on sun-dials.
In the fields of mechanics and physics he may be recognised
as the founder of statics. He examined conditions of equilibrium
of bodies, beams and levers.
In addition to translating a large number of books himself,
he founded a school of translation and supervised the
translation of a further large number of books from Greek to
Arabic.
Among Thabit's writings a large number have survived, while
several are not extant. Most of the books are on mathematics,
followed by astronomy and medicine. The books have been written
in Arabic but some are in Syriac. In the Middle Ages, some of
his books were translated into Latin by Gherard of Cremona. In
recent centuries, a number of his books have been translated
into European languages and published.
He carried further the work of the Banu Musa brothers and
later his son and grandson continued in this tradition, together
with the other members of the group. His original books as well
as his translations accomplished in the 9th century exerted a
positive influence on the development of subsequent scientific
research.