, from whom the Jews and Christians reckon their dates, and who lived about three hundred years before Christ. As for “Dhū al-Qarnayn,” mentioned in the Quran as the builder of the “barrier,” he lived long before these men. The Alexander whom Aristotle served as minister reached only Khurasan and nearby lands within the Persian Empire; he did not reach the barrier. These matters are discussed at length elsewhere.
“Ibn Sīnā” devised a philosophy combining the teachings of his Greek predecessors with what he adopted from the speculative theologians who introduced religious innovations, such as the Jahmiyyah and others like them. He followed the path of the heretical Ismā'īlīs in many of their theoretical and practical matters, blending this with some Sufi teachings. In essence, his philosophy comes back to the teachings of his Ismā'īlī, Qarmatian, esotericist brethren. His family were Ismā'īlīs, followers of al-Hākim in Egypt, and lived in his time. Their religion was that of the authors of the “Epistles of the Brethren of Purity” and others like them among the leading hypocrites of the nations, who are neither Muslims, Jews, nor Christians.
Al-Fārābī had mastered Greek letters—the teachings of Aristotle and his followers among the Peripatetic philosophers—and their musical sounds, namely the art of singing. Among these groups, then, are those who favor it and regard it as a means of purifying and disciplining souls and refining character.