Saadiah (Arabic, Said) ben Joseph, from the town Fayum in Upper Egypt (892-942), was the founder of scientific Judaism amongst the Rabbanites, and the creator of religious philosophy in the Middle Ages. He was a man of extensive knowledge who had absorbed the learning of the Mahometans and Karaites, and impregnated it with Talmudic elements. More remarkable even than his knowledge was his personality. His was a religious spirit and deep moral earnestness. He had a decided character, and belonged to those who know how to render account of their actions, and who persevere in carrying out what they think right. Little is known of his youth. There were few, if any, great Talmudical scholars in Egypt at that time, and the fact that Saadiah became famous in this branch of literature speaks well for his mental power. He was more at home in the Karaite literature than previous Rabbanites had been. In his twenty-third year (913) he made a fierce attack upon the Karaites, which was felt by them for centuries afterwards. He wrote a book "In Refutation of Anan." The contents of this book are unknown, but it is probable that Saadiah attempted to prove in it the necessity of tradition, and also to expose Anan's inconsistencies. He adduced seven arguments in proof of the necessity of tradition, which, weak as they are, were afterwards accepted for the most part by the Karaites. He wrote another book in which he showed the absurdity of the boundless extension of relationship in the Karaite law. He characterized Anan as "an ambitious man, who possessed too much boldness and too little fear of God," and who rejected Talmudic Judaism only in order to avenge a personal slight. Before he had arrived at maturity, he undertook a more difficult task, fraught with important consequences for Judaism. Hitherto, the Karaites had devoted special attention to the Scriptural text, whereas the Rabbanite teachers had, to a certain extent, neglected it, because the Talmud satisfied all the needs of their religious life.