Scientist, translator (B. 821, Harran –D. 901, Baghdad). He was born as the child of a Sabian family. At his young ages he was a jeweller. In those years, somehow he learned Arabic, Greek, Syriac and Romaic very well. Thabit, who had been at odds with Sabians at one stage due to his contrary opinions, had come across Muhammad bin Musa (D.873), who was from Banū Mūsā tribe and was later going to write important works on mechanics and mathematics, while he was on his way to Baghdad. Muhammad, who realized Thabit’s talent, offered him to participate in the translation studies in Beytü’l-Hikme (an educational institution). Thus, a while later, Thabit found the opportunity to come into the presence of Caliph el-Mutezid in Baghdad.

Thabit, who was included into the group of astrologists by the caliph, had not confined himself to this and made effort to make his relatives, Sabians, obtain a social and political footing in Baghdad and because of his closeness to the regime he achieved this goal. Thus, he rose to being the head of the Sabians in Baghdad. With the power of his position he appointed Sabians to high positions in Iraq. As a result of this, Sabians undertook significant duties and positions in bureaucracy.

One day, Thabit brought someone, who had a heart attack and was thought to be dead, back to life with the methods he used. He did not accept the suggestions that invited him to embracing Islam and thus he died as a pagan, who believed in the traditional star-planet cult of Harran. Despite all these things, his position in the palace of the Caliph was so high that he defended the Harran polytheism and paganism against Islam and other monotheist religions in the theological debates in which the sovereign himself participated.

Looking at the translations of Thabit, who was one of the most important four translators of Beytü-l-Hikme, it can be said that there are a lot of them. Therefore, it will be to the point to recall the words of Katip Çelebi who said “If Thabit ibn Qurra’s translations had not existed; no one would be able to benefit from the books on philosophy.” Almost all of the translators in the translation business were Nestorian or Jacobean Christians. Only exception of this situation was no one but the pagan philosopher Thabit ibn Qurra.

It is known that Thabit had many works in book, commentary and summary forms in mathematics, astronomy, medicine, logic, pharmacy, geometry, philosophy and music. He had also works on matters such as the formation of mountains, lunar and solar eclipses, measles and pox disease. Various numbers are alleged regarding the number of his works. According to some researchers, he has a total of 133 works with 10 of them on the history of Syrian and Sabian beliefs; according to some philosophy historians he has 150 works in Arabic and about 15 works in Syriac. More than fifty of these works had reached the present day.

When Thabit’s work called “Hermes’in Kitabı” (T.N. Book of Hermes) was translated into Arabic it served the spread of Hermetic ideology. He had especially dwelled upon Aristo’s work “Organon”. He had analyzed Plato’s “The Republic” and regarding this work he wrote a work called “Remzlerin İzahı”. Thabit, who also theorized new hypothesis in mathematics, had done researches on the entire corpus of pre-Greek era.

Thabit, who lived in the same era with Islam philosopher Kindi and famous translator Kusta b. Luka, contributed greatly to the development of logic in the Islamic world. Thabit, who also worked in the school of the great translator Huneyn b. Ishak, aided and consulted the employees of this institution. Apart from that, he rearranged and corrected the order of Huneyn b. Ishak’s philosophical and mathematical translations. As a matter of fact, he developed the theory of infinite numbers as part of a different series of infinite numbers by starting from the legacy that Euclid had left behind in the theory of numbers. Consequently, the significant role of Harran Sabians in Islamic intellectual history in translation and writing in the fields of philosophy, mathematics, medicine, astronomy and natural sciences emerged with Thabit ibn Qurra. Thabit was one of the first scholars who correctly calculated earth’s diameter and the distance between two meridians.

Thabit ibn Qurra interpreted Ptolemy’s famous work into Arabic under the name “Algamesti” and also included his knowledge on trigonometry, which was something new in his time, and astronomy. Gerard (1114-85)  translated his written works from their Arabic commentaries to Latin.  Scientists in the West had laid claim to his books, which had been translated to Latin and French in Samarkand, Baghdad and Istanbul, centuries later and today they are partly confessing it.

Upon his discoveries and inventions in his time, Thabit was tasked by Caliph Me’mun with measuring the diameter of the earth. Measurements set forth by him and other scholars were transferred to Europe through Andalusia in the following years. It is said that seamen like Christopher Columbus had found their way by using these measurements.

According to “Kamus’ul Alam” the discovery of “calculus”, which is a branch of mathematics, belongs to him as well. He named calculus “tefadul”. In another work it is said that Thabit ibn Qurra discovered the differential calculation before Newton. He did studies on positive real numbers, integral, calculus, theory of numbers, spherical trigonometry, astronomy, mechanics and statics. His studies on parabolas cleared the way for the discovery of integral calculus. Many writers say that although Qurra was aware of Archimedes’ studies, he did not use them. He precisely calculated the integral of x and root of x. His calculation was based on the use of integral sums as exponent and base. He made progress not only in astronomy but also in medicine and philosophy.

Thabit ibn Qurra’s books were read and analyzed in East and West and they had been used as sources for new and unique researches. Thabit’s works, which were read in the Islamic world as well, translated to Western languages in 12th century. According to what Beyhaki said, among his followers, his grandson Muhammad bin Cabir el-Harrani el-Battani (D.929) was the most significant one. Battani is regarded as the most prominent astronomer and scholar after the reign of Me’mun. The tradition that began with Thabit ibn Qurra, who was the ancestor of the lineage of Harran scholars, who had a say in astrologic, medical and mathematical researches, was pursued by his son, Sinan, and his two grandsons, Thabit and Ibrahim.


Kindî’ye Reddiye (Syriac), Deniz Suyunun Tuzlu Oluşunun Sebebine Dair, Calinus’un Gıdalar Üzerine Olan Kitabının Özeti, Ay Tutulmasının Belirtileri Üzerine, Güneş ve Ay Tutulmasının Nedeni Hakkında, Süryanice ve Arapça’nın Grameri Hakkında, Ölülerin Tekfini Hakkında, Sabiîler’in İtikadı Hakkında, Taharet ve Necaset Hakkında, İbadetlerin Vakitleri Hakkında.

REFERENCE: Hilmi Ziya Ülken / Uyanış Devirlerinde Tercümenin Rolü (s. 84, 1997), Şinasi Gündüz / Son Gnostikler Sâbiîler (2. baskı, 1999) - Anadolu’da Paganizm Antik Dönemde Harran ve Urfa (s. 43-44, 2005), Doç. Dr. Bayram Ali Çetinkaya (Somuncu Baba Dergisi, Ağustos 2006, s. 36-39), İhsan Işık / Ünlü Bilim Adamları (Türkiye Ünlüleri Ansiklopedisi, c. 2, 2013) -  Resimli ve Metin Örnekli Türkiye Edebiyatçılar ve Kültür Adamları Ansiklopedisi (C. 12, 2017).







Devamını Gör