Ibn Bajah (known to Europeans under the name of Avempace) was a philosoper and a poet of considerable celebrity, and a native of Saragossa, in Spain. He was attacked by some people for his religious opinions, and represented as an infidel and an atheist, professing the doctrines held by the ancient sages and philosophers. Ibn Khallikan defends Ibn Bajah, and says that these statements were much exaggerated, but adds: 'God, however, knows best what his principles were,' Abul Hassan Ali al-Imam, of Granada, was of opinion that Ibn Bajah was the greatest Arab philosopher after Al-Farabi, and places him higher than Ibn Sina and Al-Ghazali. He left numerous logical, grammatical and political works, and died at Fez in A.D. 1138.

Averroes, whose full and correct name is Abul Walid Muhammad bin Rashid, was a celebrated Arab scholar, born at Cordova A.D. 1126, and the author of many writings. He taught in his native town philosophy and medicine, two sciences which appeared for a long time to be inseparable, and the vulgar considered those professing them to be of almost supernatural attainments. The period of Averroes is that of the decadence of Arab dominion in Spain, a period when this great nation also lost the taste for sciences which it had brought to Europe. Considering the prodigious number of works composed by Averroes, who filled at the same time the offices of Imam and Kadi, his entire life must have been one of labour and meditation. He is the author of an Arabic version of Aristotle, but it is not the first which existed in that language, as some of his biographers assert, because this work had been produced already at Baghdad during the brilliant Khalifate of Mamun. There are various manuscripts of Averroes extant treating on physics, pure mathematics, astronomy and astrology, from which it would appear that, in spite of their encyclopædic attainments, the celebrated men of these times still believed in some popular errors. Science was at that time surrounded by a kind of superstitious halo of respect, to which Averroes, like so many others, is indebted for a good part of his renown. He died A.D. 1198, in the city of Morocco; his corpse was transferred to Cordova and there interred.

Medical science had already, under the second Khalif of the house of Abbas (A.D. 754-775), enjoyed the highest honours, which it ever afterwards retained. Great physicians were brought from the Persian hospital of Jondshapur, and between the years A.D. 750 and 850 the number of physicians was considerable, but only the most celebrated will be noticed.

Georgios (Jorjis) bin Bakhtyeshun, of Jondshapur, lived at the commencement of the Abbaside dynasty, and was the author of the book of Pandects. When Al-Mansur was building the city of Baghdad he suffered from pains in his stomach and from impotency, and Georgios, the director of the medical college at Jondshapur, was recommended to him as the most skilled physician of the time. Accordingly, the Khalif directed Georgios and two of his pupils, Ibrahim and Serjis, to come to Baghdad, appointing Gabriel (Jebrayl), the son of Georgios, as director of the hospital in the place of his father. Georgios cured Al-Mansur, and received from him three thousand ducats for his reward, along with a beautiful slave girl; the latter was, however, returned to the Khalif with thanks, and the remark that, 'being a Christian, he could not keep more than one wife.' From that moment the physician attained free access to the harem, and enjoyed high favour with the Khalif, who greatly pressed him in A.D. 770 to make a profession of Islam; but this he refused to do, and died shortly afterwards, in A.D. 771. Before his death Georgios asked to be allowed to return to Jondshapur, to be buried there with his ancestors. Al-Mansur said, 'Fear God, and I guarantee you paradise.' Georgios replied, 'I am satisfied to be with my ancestors, be it in paradise or be it in hell.' The Khalif laughed, allowed him to return home, and presented him with ten thousand pieces of gold for his travelling, expenses.

Gabriel (Jebrayl), the son of the above-named Georgios (Jorjis), was also a celebrated physician. He enjoyed great favour with Harun-ar-Rashid, who used to declare that he would not refuse him anything. When, however, this Khalif fell ill at Tus, and asked Gabriel for his opinion, the latter replied that if Harun had followed his advice to be moderate in sexual pleasure, he would not have been attacked by the disease. For this reply he was thrown into prison, and his life was saved only by the chamberlain Rabi'i, who was very fond of him. Amin, the son and successor of Rashid, followed the advice of Gabriel more than his father did, and would not eat or drink anything without his doctor's sanction. In A.D. 817 Gabriel cured Sehl bin Hasan, who recommended him to Mamun; but Michael, the son-in-law of Gabriel, was his body physician. In A.D. 825 Mamun fell sick, and, as all the medicines of Michael were of no use, Isa, the brother of Mamun, advised him to get himself treated by Gabriel, who had known him from boyhood; but Abu Ishak, the other brother of Mamun, called in Yahya bin Maseweih, and when he could do nothing, then Mamun sent for Gabriel, who restored him to health in three days, and was handsomely rewarded in consequence. When Mamun marched, in A.D. 828, against the Byzantines, Gabriel fell sick and died, whereon the Khalif took Gabriel's son with him on the campaign, he being also an intelligent and skilled physician.

The works of Gabriel are:

(1) A treatise on food and drink, dedicated to Mamun.

(2) An introduction to logic.

(3) Extracts from medical Pandects.

(4) A book on fumigatories.