THABIT IBN QURRA

born c. 836, , Syria died 901, Baghdad, Iraq in full Al-Sabi' Thabit ibn Qurra al-Harrani Arab mathematician, astronomer, physician, and philosopher, a representative of the flourishing Arab-Islamic culture of the 9th century. Thabit was a scion of a prominent family settled in Harran, a city noted as the seat of a Hellenized Semitic astronomical cult of which Thabit was a member. By calling themselves Sabians, after a group mentioned in the Qur'an, the cult members established themselves as People of the Book and hence were freed from the requirement of conversion to Islam. Some sources describe Thabit as a money changer in Harran, and, although the sources give two different accounts of his life, both agree that he went to Baghdad to work for three wealthy brothers, known as the Banu Musa, translating Greek mathematical texts. Among the major Greek mathematicians whose works he translated (or whose translations he revised) were Euclid, Archimedes, Apollonius of Perga, and Ptolemy. He also prepared summaries of the works of the physicians Galen of Pergamum and Hippocrates as well as the philosophy of Aristotle. He soon wrote original works on geometry, statics, magic squares, the theory of numbers, music, astronomy, medicine, and philosophy. Through the influence of the mathematician Muhammad ibn Musa ibn Shakir (father of the three famous Banu Musa mathematician brothers), late in his life Thabit ibn Qurrah became court astronomer for the 'Abbasid caliph al-Mu'tadid (reigned 892902). Several of Thabit ibn Qurrah's works were translated into Latin and Hebrew and proved to be influential in the Latin West. A son, Sinan ibn Thabit, became a renowned physician and director of a hospital in Baghdad, and a grandson, Ibrahim ibn Sinan, won fame as an important mathematician.