Qāḍīzāde al‐Rūmī: Ṣalāḥ al‐Dīn Mūsā ibn Muḥammad ibn Maḥmūd
al‐Rūmī
F. Jamil Ragep
Born Bursa (Turkey),
circa 1359
Died Samarqand (Uzbekistan),
after 1440
Qāḍīzāde
al‐Rūmī was known for his works in mathematics and astronomy,
which were used extensively as teaching texts. He left his native Bursa,
where his grandfather had been a prominent judge and his father an eminent
scholar, and traveled to Persia in order to gain a higher level of proficiency
in the philosophical and mathematical sciences. His nickname indicates his
family's standing (Qāḍīzāde = son of the
judge) and his origins (Rūmī = from what had been part of the
eastern Roman Empire). He studied with many learned scholars in Khurāsān
and Transoxiana, among whom was the famous theologian al‐Sayyid
al‐Sharīf al‐Jurjānī at the court of
Tīmūr in Samarqand. Qāḍīzāde, however, felt
that Jurjānī was deficient in the mathematical sciences. After
Tīmūr's death, Qāḍīzāde
found both a student and a patron in Tīmūr's grandson Ulugh
Beg, also in Samarqand.
Qāḍīzāde
joined a group of scholars in the circle of Ulugh Beg that taught mathematics
and astronomy, as well as other sciences. He became the head of the madrasa
(school) of Samarqand, and Ulugh Beg often attended his lectures. Qāḍīzāde also became
one of the directors of the Samarqand Observatory after the death of
Jamshīd al‐Kāshī in 1429, and he undertook
its observational programs assisted by ʿAlī al‐Qūshjī, who continued the program after
Qāḍīzāde's
death.
Qāḍīzāde
was not known for his innovations or creativity. He was most famous for
his commentaries on Maḥmūd
al‐Jaghmīnī's
astronomical compendium entitled al‐Mulakhkhaṣ fī ʿilm
al‐hayʾa al‐basīṭa (1412) and Shams
al‐Dīn al‐Samarqandī's geometrical tract Ashkāl al‐taʾsīs
(completed: 1412); the large number of extant manuscripts of both commentaries
indicates their enduring popularity as teaching texts. Therefore, it is
not surprising that one also finds supercommentaries on Qāḍīzāde's
commentaries written by many scholar–teachers including Sinān Pāshā
(died: 1486), ʿAbd al‐ʿAlī al‐Bīrjandī (died: 1525/1526), Bahāʾ
al‐Dīn al‐ʿĀmilī (died: 1621), and Qāḍīzāde's
student Fatḥallāh
al‐Shirwānī (died: 1486). All of these individuals
continued the tradition established at Samarqand, thereby disseminating
the mathematical sciences throughout Ottoman and Persian lands. Also noteworthy
is that the marriage of Qāḍīzāde's son to Qūshjī's
daughter would eventually sire the famous Ottoman astronomer–mathematician
Mīram Čelebī (died:
1525).
A number of other astronomical works are sometimes attributed to Qāḍīzāde, including a
supercommentary on Ṭūsī's commentary (taḥrīr) of the Almagest
and a treatise on the sine quadrant, but it is not clear which of these
are authentic. The ascription of a commentary (Sharḥ) on Naṣīr
al-Dīn al-Ṭūsī's major astronomical work al‐Tadhkira
fī ʿilm
al‐hayʾa (Biblioteca Medicea Laurenziana or. MS 271) to Qāḍīzāde
is certainly not correct; this manuscript is actually an incomplete copy
of the commentary by Jurjānī.
Among Qāḍīzāde's
mathematical works is a treatise on determining the value of sin 1°, for
which he seems to have relied heavily on the work of Kāshī. Qāḍīzāde's
only philosophical or theological work is a supercommentary on Athīr
al‐Dīn al‐Abharī's
Hidāyat al‐ḥikma, although he intended
to write a refutation of parts of Jurjānī's famous commentary
on the Persian ʿAḍud
al‐Dīn al‐Ījī's (circa: 1281–1355) Mawāqif.
Selected References
Bagheri, Mohammad (1997). “A Newly Found Letter of Al‐Kāshī
on Scientific Life in Samarkand.” Historia Mathematica 24: 241–256.
Brockelmann, Carl. Geschichte der arabischen Litteratur.
2nd ed. Vol. 1 (1943): 616–617, 624, 674–675; Vol. 2 (1949): 275, 276; Suppl.
1 (1937): 850, 865. Leiden: E. J. Brill.
Fazlıoğlu, İhsan (2003). “Osmanlı felsefe‐biliminin
arkaplanı: Semerkand matematik‐astronomi okulu.” Dîvân İlmî
Araştırmalar1: 1–66.
Kennedy, E. S. (1960).
“A Letter of Jamshīd al‐Kāshī to His Father: Scientific
Research and Personalities at a Fifteenth Century Court.” Orientalia
29: 191–213. (Reprinted in E. S. Kennedy, et al. (1983). Studies
in the Islamic Exact Sciences, edited by David A. King and Mary Helen
Kennedy, pp. 722–744. Beirut: American University of Beirut.)
Rosenfeld, B. A. and Ekmeleddin Ihsanoğlu (2003). Mathematicians,
Astronomers, and Other Scholars of Islamic Civilization and Their Works (7th–19th
c.). Istanbul: IRCICA, pp. 272–274.
Sayılı, Aydın (1960). The Observatory in Islam.
Ankara: Turkish Historical Society.
Tashköprüzāde
(1985). Al‐Shaqāiʾq al‐nuʿmāniyya
fī ʿulamāʾ
al‐dawlat al‐ʿuthmāniyya, edited
by Ahmed Subhi Furat. Istanbul: Istanbul University. pp. 14–17.