In the passage already quoted Maqrizi describes ʿAbdullah as “learned in all the canon law and customs and sects,” so that it seems that he, the fortune teller’s son, was credited with being the original teacher and founder of the sect. Perhaps Maymun himself was the founder of a minor off-shoot of the Ismaʿilian body,—we hear of followers who went with him to Jerusalem,—and ʿAbdullah succeeded him as head of this group but, himself a student of philosophy like so many other Shiʿites, and participating in rationalistic opinions, used his position to form a kind of free-masonry, in which he developed more fully the principles already indicated by Jaʿfar as-Sadiq, and so made the Aristotelian and neo-Platonic teaching somewhat modified in a Persian guise, the “hidden meaning” of the Qurʾan. Probably he too was responsible for the efficient organizing of the sect, although its missionary propaganda was, as has been noted, reproduced from that of the Hashimites. He is said to have been the author of a book called _al-Mizan_, “the balance” (Abulfeda: _Ann. Mus._, ii. 310). According to Nuwairi, who used the history of Abu l-Hasan b. ʿAli Akhu-Muhsin, himself a descendant of Ismaʿil b. Jaʿfar and a contemporary of the chief activity of the Ismaʿilian sect, ʿAbdullah assumed Shiʿite views, not because he wanted to get men to recognise the Imamate of Ismaʿil or his son Muhammad, but simply as a device to attract adherents: such was Akhu-Muhsin’s view, no doubt a prejudiced one, but of some weight as undoubtedly the judgment of many contemporaries. It is, however, quite as probable that the ʿAlid theories were derived from the existing sect of which Maymun had been head, and were left unaltered by his son when he took it in hand.