علم الزمن والوقت
Abu Sahl Wayjan ibn Rustam Al-Quhi
(Bijan Al-Quhi) Al- Tabaristani
(Died in 405 A.H/ 1014 A.D) said to have died in (390 A.H/ 1000 A.D)
Profile:
Al-Quhi is one of the prominent astronomers, who represents the scientific renaissance age in the Islamic heritage between the 3rd and the 4th hijri century; his books in “time science” are between the philosophical research: like treating the topic of finite and infinite time; practical field observatory. He was the head of the observatory in Baghdad. He was known for solving mathematical problems such as the transformation between the flat shape and spherical shape; as well as he cared about determining Qibla direction for religious purposes, as well as he contributed to craft by writing about “making the Astrolabe”.
Unfortunately, however, only few of his important Arabic books remained today, because most of his books were translated into Latin and into most important European languages in the Middle Ages, then his name was erased and some Western scholars posed most of his theories and opinions in most of the sciences he developed.
Today, we hardly find a single title published in Arabic among the several books he wrote about astronomy and time science, however, his mathematical book “Al-Barkar Al-Tam wa Al-Amalu Bihi” is available today. The content of the two articles indicates his intention to make a new machine that none has created before, as well as he developed the Astrolabe and solved the problems he faced when he was making them. He said in the conclusion of the book: “that’s what we wanted to explain ……………………………………….”.
Al-Quhi devoted his life to observing space and writing; which is the perfect image for scholars today, therefore, neither the social circumstances, nor the political interest, nor his living and economic needs kept him away from that; he focused on only one interest, which not so many scholars did.
It is noted through the personality of Al-Quhi that he is an international scientific and Islamic heritage personality, from Persia, but worked in the Observatory of Baghdad. This scientific freedom and movement are the basic condition for the development of sciences; because the image of the modern state and the restrictions of scholar’s freedom of movement for security or political considerations have hindered his academic production, dwarfed his geographical borders and reduced his perception and his epistemological boundaries.
Perhaps the quality of “scholar’s freedom” can be enough to judge nations and states; the more developed they are, the more fortunate and the freer scholars they would be. However, whenever freedoms are restricted -as taking place in the Islamic world centuries after Al-Quhi- the more backward, fragile and subordinate these states would be and vice versa.
The west in our age tended to limit the oriental scholar’s movement and the Muslim’s in particular, unless they acquire “its convictions and its science”, on the other hand, other scholars from other areas have been given total freedom and action.
Biography:
He was one of the scholars whom Adud Al-Dawla counted on for the observation of space. He was a mathematician who cared about geometry, and Cantor mentioned his geometric contributions to sphere and surface, he solved the problem of triangulation of the angle and was the first scholar to solve mechanical problems in a mathematical method.
Some of his books are: Rissala fi Al-Berkar wa Al-Amel Al-Tam bihi, Istikhrej Khattayn byna Khatayn, Rissala fi Istikhrej Al-Mujassam Al-Mukafi’, Marakiz al-Dawair Al-Mutamassa ala Al-Khutut bi Tarik Al-Tahlil, Al-Massa’il Al-Handassiya (Geometric matters), and Kitab Al-Akar.
He had a report in the observatory that he ruled, which was visited by rulers and scholars and signed up a copy of it, which includes all the details. In fact, some high-quality copies are left, in the book of “Ikhbar Al-Ulama by Al-Qifti” a copy of the book was published along with the content.
He lived during the rule of Adud Al-Dawla and Sharaf Al-Dawla Buyid and lived in Baghdad. He belongs to Al-Quhi dynasty in Tabaristan mountains in the southern Caspian Sea.
His impacts on the field of “time” is numerous, which are as follow:
– “Qawl Ana fi Az-Zaman Al-Mutanahi Haraka Ghyr Mutanahia (A Message on Finite Time is an Infinite Movement”.
– “Mahdar fi Rasd Medkhal Al-Shams Ra’say As-Saratan wa Al-Mizan”.
– “Risala fi Ma’rifat Miqdar Al-Bud min Marqaz Al-Ard wa Makan Al-Qawaqib Al-Dhi Yanqus Billayl (A Message on Identifying the Distance between the Center of the Earth and Planets)”.
– A book without title about “Istikhraj Matla’ Qaws Malum fi Al-Mayl fi Makanin ma, Di Ardin Malum Aw Muadalatuhu fi Al-Nahar”.
– Taqsim Al-Qura bi Sutuh Mustawyia fi Sinaat Al-Astrolabe “Dividing the Sphere in Equal Surface”.
– “Kitab San’at Al-Astrolabe (A Book on Making the Astrolabe)”.
– “Istikhraj Samt Al-Qibla (Determining the Qibla Direction)”.
– “Risala fi Ma’rifat Ma Yura min As-Sama wa Al-Bahr (A Message on Knowing what can be Seen in the Sky and the Sea)”.
Abu Sa’d ibn Sahl has a book entitled “Sharh Kitab San’at Al-Astrolabe li-Abi Sahl Al-Quhi (Explanatory of the Book of Making the Astrolabe by Abu Sahl Al-Quhi)”.
Sources:
Al-Qifti: Ikhbar Al-Ulama; P262-264. Sezgin: History of Heritage; part 5/ P395. Qadri Tuqan: Arab Scientific Heritage; P128-130. “Risala fi Al-Berkan Al-Tam wa Al-Amel bihi”, a copy from the Internet, copies of Baylak bin Abdullah al-Qibjaqi, date 649 A.H / 1251 A.D.
Written by: Dr. Mohamed Babaami
Translated by: Toufik Achour
Date: 04/06/2023
The Article title in Arabic: الكوهي
