The Golden Islamic Age: Mathematician Muhammad Ibn Musa al-Khwarizmi, whose work was considered "dangerous" and "magical"




Suppose a man frees two slaves in a state of sickness. One of them costs 300 dirhams and the other 500 dirhams. The slave who was worth 300 dirhams dies in a short time and leaves only one daughter among his heirs. Then the master of those slaves also dies and their heir is also their only daughter. The deceased slave leaves behind a property worth 400 dirhams. So how much of the inheritance will come to everyone now? '





This confusing question of mathematics is taken from a book written in the early ninth century AD. This issue actually provides guidance on the division of property among the heirs. Written in Arabic, the book is known worldwide as Kitab al-Jabr.


The author of this book is the subject of our writing today and it was Muhammad Ibn Musa Al-Khwarizmi who mastered many subjects in the Middle Ages. I first heard his name in a history essay when I was in a school in Iraq.


He writes for the first time in this book on the subject of "algebra", the word is taken directly from the title of this book and it has been given the status of a sub-field of mathematics.


Khwarizmi was originally born around 780 AD and, as his name suggests, belonged to the province of Khwarizm in the Central Asian country of Uzbekistan.


We have very little information about his life, but we do know that he came to Baghdad in the early ninth century. At that time, Baghdad was the capital of a vast Islamic empire ruled by the powerful Abbasid Caliphate.


He worked for Caliph Al-Mamun. Caliph Mamun, himself a fanatic of translating Greek books into Arabic, was one of the leading figures in the history of scientific research and its importance.


Al-Khwarizmi worked at the, an institution that sounded fictitious. It was the center of original research in translation and the scientific sciences, and gathered the great minds of an age known as the Golden Age of Arabic science.


The word Arabic is used here because most of the books were written in Arabic at that time because it was not only the official language of the empire but also the holy book of Muslims, the Qur'an, was revealed in that language.


These scientific books covered a variety of scientific disciplines, including philosophy, medicine, mathematics, optics, and astronomy. Among the great scientific achievements of this period, we will mention some of the achievements that were directly related to al-Khwarizmi.


In the second decade of the ninth century, Caliph al-Mamun established observatories in Baghdad to study astronomy. One or two years later, a critical examination of Greek astronomy began. During this time, several researchers under the auspices of Al-Khwarizmi made several observations on the sun and the moon.


During this time, a table of latitudes and longitudes of 22 stars at the same location was created. Al-Mamun, meanwhile, ordered the construction of another observatory on the slopes of Mount Qassion, overlooking the city of Damascus. The purpose of building the observatory was to gather more data in this regard.


By the end of the work, Al-Khwarizmi and his colleagues had compiled statistics tables on the location of several stars.

The Greek astronomer Tonomi, in his famous book, The Geography, recorded everything that existed about geography around the world. It is said that the Arabic translation of his work aroused the interest of the Islamic world in geography.


Al-Mamoun instructed his scholars to draw a new map of the world, as Tonomi's maps did not include major Islamic cities such as Mecca or the capital, Baghdad. Mecca was not so important during the Tonomi period and Baghdad did not come into existence at that time.


Al-Khwarizmi and his colleagues decided to measure the distance between the two cities. In this regard, they measured and took statistics during the lunar eclipse.


The distance they drew between the two cities in this ancient period was less than two per cent inaccurate compared to the present day figures. He then tried to re-examine the letters of other important places which could determine the location of the focal point of these places.


His maps, for example, show the Atlantic Ocean and the Indian Ocean as open waterways, not land-bound seas, as Tonomi described in his book.


Al-Khwarizmi's book "Surat al-Ard" means he has the honor of being the first geographer of Islam. This book was completed in 833 AD. It is also the year of the death of Caliph al-Mamun. The book contained tables of latitudes and longitudes of 500 cities.


In this book, different places are divided into towns, rivers, mountains, seas and islands. In each table, these places were arranged from south to north.


However, all these achievements are blurred in the face of his achievements in the field of mathematics. Due to his essays on numbers and numerals, the decimal number system was introduced in the Muslim world. His book Al-Jum Wal-Tafriq B-Hind is of great importance in the sub-field of mathematics.


This book was written around 825 AD, but there is no authentic Arabic translation and the title of the book is only an estimate.


However, it was probably the first book written on the decimal system to be translated into Latin. It begins with the words written in Latin, "Al-Khwarizmi said ..."


This book gives various instructions on arithmetic and hence the term algorithm which is actually the way to speak algorithm in Latin.


In fact, this and earlier translations of Al-Khwarizmi's work were criticized in Europe, a time when Europe was going through a dark period. That is why Khwarizmi's work was considered 'dangerous' or 'magical'.


His greatest work was certainly his book on algebra. Al-Khwarizmi was a follower of the ancient Persian religion Zoroastrianism and we think he later converted to Islam. On the very first page of the book Al-Jabr, it is written in the name of Allah, the Most Gracious, the Most Merciful. Even today, most books written by Muslim writers begin with this sentence.


However, al-Khwarizmi may have written this in keeping with tradition, because he did not want to offend a Muslim caliph who had his full support. In this book, al-Khwarizmi combined obscure rules of mathematics that only a few people knew about.


He then drafted the rules into guidelines that could address everyday issues such as inheritance, trade and agriculture.

It is also important to commend the Muslim mathematicians who came after al-Khwarizmi, who publicized his work and provided evidence of its authenticity after the impact of his work on Europe.


His book was translated twice into Latin in the 12th century. Once by Robert Ochester of Great Britain and once by Gerard of Cremona, Italy.


His work was also known to Fabanachi, arguably the greatest mathematician of the Middle Ages. He also cites al-Khwarizmi's work in his famous book, Labor Abachi.


Here we need to be careful that we do not attribute the credit for inventing a branch of mathematics to Al-Khwarizmi, simply because the name we use for it today, 'Algebra', is the name of Al-Khwarizmi's book. Came into being from