CHAPTER VI
THE DEVELOPMENT OF THE NUMERALS AMONG THE ARABS
If the numerals had their origin in India, as seems most probable, when did the Arabs come to know of them? It is customary to say that it was due to the influence of Mohammedanism that learning spread through Persia and Arabia; and so it was, in part. But learning was already respected in these countries long before Mohammed appeared, and commerce flourished all through this region. In Persia, for example, the reign of Khosrū Nuśīrwān,[[364]] the great contemporary of Justinian the law-maker, was characterized not only by an improvement in social and economic conditions, but by the cultivation of letters. Khosrū fostered learning, inviting to his court scholars from Greece, and encouraging the introduction of culture from the West as well as from the East. At this time Aristotle and Plato were translated, and portions of the Hito-padēśa, or Fables of Pilpay, were rendered from the Sanskrit into Persian. All this means that some three centuries before the great intellectual ascendancy of Bagdad a similar fostering of learning was taking place in Persia, and under pre-Mohammedan influences.
The first definite trace that we have of the introduction of the Hindu system into Arabia dates from 773 A.D.,[[365]] when an Indian astronomer visited the court of the caliph, bringing with him astronomical tables which at the caliph's command were translated into Arabic by Al-Fazārī.[[366]] Al-Khowārazmī and Ḥabash (Aḥmed ibn ‛Abdallāh, died c. 870) based their well-known tables upon the work of Al-Fāzarī. It may be asserted as highly probable that the numerals came at the same time as the tables. They were certainly known a few decades later, and before 825 A.D., about which time the original of the Algoritmi de numero Indorum was written, as that work makes no pretense of being the first work to treat of the Hindu numerals.
The three writers mentioned cover the period from the end of the eighth to the end of the ninth century. While the historians Al-Maś‛ūdī and Al-Bīrūnī follow quite closely upon the men mentioned, it is well to note again the Arab writers on Hindu arithmetic, contemporary with Al-Khowārazmī, who were mentioned in chapter I, viz. Al-Kindī, Sened ibn ‛Alī, and Al-Ṣūfī.
For over five hundred years Arabic writers and others continued to apply to works on arithmetic the name "Indian." In the tenth century such writers are ‛Abdallāh ibn al-Ḥasan, Abū 'l-Qāsim[[367]] (died 987 A.D.) of Antioch, and Moḥammed ibn ‛Abdallāh, Abū Naṣr[[368]] (c. 982), of Kalwādā near Bagdad. Others of the same period or
earlier (since they are mentioned in the Fihrist,[[369]] 987 A.D.), who explicitly use the word "Hindu" or "Indian," are Sinān ibn al-Fatḥ[[370]] of Ḥarrān, and Ahmed ibn ‛Omar, al-Karābīsī.[[371]] In the eleventh century come Al-Bīrūnī[[372]] (973-1048) and ‛Ali ibn Aḥmed, Abū 'l-Ḥasan, Al-Nasawī[[373]] (c. 1030). The following century brings similar works by Ishāq ibn Yūsuf al-Ṣardafī[[374]] and Samū'īl ibn Yaḥyā ibn ‛Abbās al-Maġrebī al-Andalusī[[375]] (c. 1174), and in the thirteenth century are ‛Abdallatīf ibn Yūsuf ibn Moḥammed, Muwaffaq al-Dīn Abū Moḥammed al-Baġdādī[[376]] (c. 1231), and Ibn al-Bannā.[[377]]