Beruni and his teacher’s groundbreaking discovery

 

As we turn the pages of history and examine the lives of great scholars, we witness how the tradition of mentorship has played a pivotal role in their intellectual development, growth, and global recognition. One of the brightest figures of the Islamic Renaissance Abu Rayḥan Muḥammad ibn Aḥmad al-Beruni enriched global science with his unique contributions in cosmology, geodesy, mathematical analysis, history, and philosophy. However, a name deserving special reverence is that of Abu Nasr Mansur ibn Ali ibn al-Iraq the scholar who laid a profound intellectual and moral foundation in Beruni’s journey toward excellence.

 

Abu Nasr al-Iraq was not only Beruni’s mentor but also someone who deeply understood and appreciated his extraordinary talent. He revealed to Beruni the most complex secrets of science and regarded him not merely as a student but as an equal among the learned. Having immense faith in Beruni’s potential, Abu Nasr dedicated twelve scientific treatises to him, focusing on theoretical questions of the celestial sphere, geodetic astronomy, and the classical “Zij” works. This remarkable scientific and spiritual collaboration formed one of the most distinguished teacher-student schools in the Muslim East.

 

Abu Nasr Mansur ibn Ali ibn al-Iraq was a prominent scholar of the 11th-century Muslim East who advanced mathematical and geometric thinking, perfected spherical trigonometry, and developed astronomical tables and theories. His scientific research left a significant impact not only in his time but also for centuries to come. His treatise Shah Almagest, his proof of the sine theorem for spherical triangles, and his innovative method for determining the angle of inclination between the equator and the ecliptic all established him as one of the leading scientific minds of his era.

 

 

Scientific Legacy

 

Approximately 30 of his works are known, and they continue to be studied in both Eastern and Western academic circles today. Among these are treatises focused on theoretical and practical issues such as spherical geometry, the construction of astronomical tables, the sine theorem, and the relationships between the equator and the ecliptic.

 

“Shah Almagesti” – A New Turning Point in Eastern Science

 

One of Abu Nasr al-Iraq’s most renowned works is the astronomical treatise titled al-Majisti ash-Shahi, or Shah Almagesti. This work was dedicated to the Khwarazmshah Ali ibn Ma’mun and aimed to update Ptolemy’s Almagest in accordance with the scientific spirit of the time.

 

In this treatise, he made critical corrections to the astronomical tables and calculations of the famous 9th-century astronomer Ḥabash al-Ḥasib and the 10th-century scholar Abu Ja’far al-Khazin, based on in-depth scientific analysis. Notably, he proposed an entirely new method for determining the angle of inclination between the ecliptic and the celestial equator an approach previously unused. This method later found wide application in both Western and Eastern schools of astronomy.

 

Founder of Trigonometric Thought

 

Abu Nasr al-Iraq is considered one of the foundational figures behind the spherical trigonometric theorems taught in mathematics departments and classrooms today. He was among the first scholars to theoretically prove the sine theorem for triangles situated in space (i.e., on a sphere). This achievement laid the groundwork not only for astronomy but also for geodesy, cartography, and modern space calculations.

 

His accomplishments were highly praised not only by al-Beruni but also by subsequent great thinkers such as Nasir al-Din al-Ṭusi, Ulugh Beg Mirzo, and scholars from Western Europe. It is particularly noteworthy that the discipline of spherical trigonometry was established as a distinct scientific field largely thanks to al-Iraq’s efforts.

 

Abu Rayhan al-Beruni: a disciple or a successor?

 

To fully understand the scientific legacy of Abu Nasr al-Iraq, one must grasp his complex yet sincere relationship with his student Abu Rayḥan al-Beruni. Al-Beruni regarded al-Iraq not only as a teacher but also as an intellectual peer and collaborator. Out of deep respect, he mentioned his teacher’s name prominently in the introductions to his own works.

 

Al-Iraq, in turn, authored twelve treatises dedicated to al-Beruni, each of which was aimed at providing a foundation for his student’s scientific inquiries:

 

Theoretical issues related to the celestial sphere,

 

Revisions and reinterpretations of ancient Zij astronomical tables,

 

Analyses of geometric equations,

 

Treatises on geodesy and methods of measuring the Earth’s surface.

 

These works served not only as theoretical and methodological guidance for his student but also as a symbol of scholarly continuity across generations in the Eastern scientific tradition.

 

 

Influence on Western science and rediscovery in the 20th century

 

Although the works and ideas of Abu Nasr al-Iraq did not reach the West directly during the medieval period, their influence entered Europe via al-Andalus. In particular, his methods of spherical trigonometry and the construction of astronomical tables introduced new approaches for Western scholars.

 

He was rediscovered in the 20th century. Prominent scholars such as:

 

Paul Luckey (Germany),

 

Edward S. Kennedy (USA),

 

Julio Samsó (Spain),

 

Kurt Jansen (Netherlands),

 

analyzed his legacy and highly praised the scientific value of his works. Notably, in 1910, G. Suter translated and published al-Iraq’s treatise Answers to Questions on Geometry into German. This translation marked an important step toward restoring the rightful place of Muslim scholars in the history of European science.

 

Abu Nasr Mansur ibn Ali ibn al-Iraq remains a pillar of scientific thought in his time and a guiding star for future generations. His mathematical investigations, analyses of the celestial sphere, and success in establishing a scholarly school through his student al-Beruni have earned him a lasting place in the annals of world science.

 

Today, reviving the name of Abu Nasr al-Iraq, studying his works, and transmitting them to the younger generation is not merely an act of historical reverence it is a pressing matter of service to scientific progress.

Throughout the history of the Islamic world, thousands of scholars have lived and made invaluable contributions to the advancement of science. Their names are not just memories of the past, but guiding stars for the present generation. At the Center of Islamic Civilization in Uzbekistan, the lives, scientific views, and discoveries of such great figures are presented through immersive exhibitions. Every corner of the Center is a bridge between past and present; every exhibit is an invitation to reflect.

 

Scholars like Abu Rayḥan al-Beruni and his mentor Abu Nasr Mansur are the very individuals who laid the foundations of modern science and inspired today’s technologies. Their theories in astronomy, innovations in mathematics, and perspectives in philosophy and natural science remain highly relevant today. The Center of Islamic Civilization conveys this invaluable legacy, their intellectual breadth, and scientific courage to the younger generation in a modern, accessible language.

 

This Center is not a museum it is a journey through time; not a mere collection of artifacts but a revival of thought. Here, the future recognizes its roots, and knowledge discovers its own history. In this space, the past is not just a stage once lived, but a platform for present-day development. With this very approach, the Center serves as a unique hub not only preserving cultural heritage, but embedding it into the consciousness of the modern generation.

 

Husan TURSUNOV

P.S.: The article may be used with reference to the official website of the Center.