2. Al-Khawarizmi
(Died 236H/850AD) 

Al-Khawarizmi was one of the greatest Arab and world scholars whose works had a significant influence on mathematics and astronomy.  In this connection, Aldo Mili says : "If we move to mathematics and astronomy, we will find from the beginning top level scholars, such as the illustrious Abu Abdullah Mohammad Ibn Musa al-Khawarizmi"(9).

The date of his birth is unknown while the date of his death is inexact. The only precise information available about him is that he was born at Khawarizm (Kheva), south of the Aral sea. He lived in Baghdad during the rule the Abbassid caliph Al-Mamun who appointed him as the chief librarian of his library and entrusted him with the task of gathering and translating Greek books(10). Al-Khawarizmi  draw an enormous benefit from the books of Al-Mamun library. He studied mathematics, geography, astronomy, history in addition to his in-depth Greek and Hindu knowledge.

Scientific Contributions

Al-Khawarizmi laid the foundations of algebra as a independent science separate from arithmetic, that was later adopted by Europeans. He was the first to have used the term of algebra. Up to now, algebra is known by its Arabic name in all European languages. All the terms in European languages ending by "algorithm" are named after him. He was the first scientist to have ever written in the field of algebra. He had also the merit to introduce the Indian system of numerals (now generally known as Arabic numerals). Amongst the major contributions he made to mathematics was his discovery and development of some procedures, such as the calculus of two errors, the geometrical solution of quadratic equations. He published the first Arabic trigonometric tables which were translated in Latin in the 12th century.

In addition to his great contributions in arithmetic, al-Khawarizmi innovated in the field of astronomy and developed research in trigonometry and developed ephemerides which had a considerable impact on the other tables developed by Arabs afterwards(11).

The other scientific contributions of al-Khawarizmi were the improvements brought on Ptolemy's views on geography as well on his maps.

Major Works

Al-Khawarizmi wrote several books, the most important of which are :

- Al-Jabr wa-al-Muqabilah, (Book on Integration and Equation) an unprecedented book wrote at the request of the Caliph al-Mamun. This book not only coined the word of algebra and gave it its present meaning but it also opened verily a new era in mathematics(12). It was translated in Latin during the 12th century, and thanks to this translation, this science reached the West. For several centuries afterwards, this book constituted a reference in Europe. It was annotated by Dr. Ali Musharafa and Dr. Muhamad Mursi Ahmed and was published for the first time in Cairo in 1939AD.

- Kitab Surat-al-Ard, a manuscript kept today in Strasbourg, France. This book was translated in Latin and the information it contained was confronted to Ptolemy's views(13).

- Kitab al-Amal bi al-Usturlab (Use of the Astrolabe) and Kitab Amal al-Usturlab (Astrolabe's Operation).

In brief, al-Khawarizmi was undoubtedly among the greatest scholars of his time and had the merit of introducing the Indian numeral system both to Arabs and to the Western world(14).

In fact, he was the founder of algebra and left several treaties in arithmetic, astronomy and geography. In his words, Aldo Milli paid tribute to the eminence of al-Khawarizmi by saying : "al-Khawarizmi opened the lead for a series of great mathematicians"(15). His books were taught in European universities until the 16th century.