The translation of the works of Aristotle, as indeed of all the Greek authors, was made by Syrian and Chaldean Christians, and {182} especially by the Nestorians who, as physicians, were in high favour with the liberal Khalifs of the 'Abbasside dynasty. In some cases the translation into Arabic was made from Syriac versions, for in the time of the Emperor Justinian many Greek works had been translated into the latter language. The most celebrated translator was the historian physician Honein-Ibn-Ishak (died 876 A.D.), a man profoundly acquainted with the Syriac, Greek and Arabic languages. He was at the head of a school of interpreters in Baghdad, to which his son Ishak-ben-Honein and his nephew Hobeisch-Al-Asam also belonged. In the tenth century (A.D.) Yahya-ben-Adi and Isa-ben-Zara'a translated some works and corrected earlier translations of others. It is to these men that the Arabs owe their chief acquaintance with Plato. The study of Aristotle spread rapidly amongst the Muslim people, especially amongst the heretical sects. The orthodox looked with grave suspicion on the movement, but could not for a while stay the impulse. The historian Makrizi says: "The doctrine of the Philosophers has worked amongst the Muslims evils most fatal. It serves only to augment the errors of the heretics and to increase their impiety."[178] It came into contact with Muslim dogmas in such subjects as the creation of the world, the special providence of God and the nature of the divine attributes. To a certain extent the Mutazilites were supported by the philosophical theories they embraced, but this did not diminish the disfavour with which the orthodox looked upon the study of philosophy. Still it grew, and men in self defence had to adopt philosophic methods. Thus arose a later system of scholasticism. The earlier system was confined mainly to matters of religion; the later school occupied itself with the whole range of philosophic investigation, and thus went farther and farther away from orthodox Islam. The Muslims themselves did not write books on philosophy in the earlier period. Men of liberal tendencies imbibed its teaching, but orthodoxy finally gained the day over the earlier scholastics, and in the form known as that of the Ash'arian School became again supreme.[179] The great intellectual movement of the Philosophers proper, the later scholastics (Mutakalliman), lasted longer, but by the end of the twelfth century (A.D.) the whole Muhammadan world had again become orthodox. Salah-ud-din (Saladin) and his successors in Egypt were strong supporters of the Ash'arians. {183}