The Fatimides conquered Sicily and Calabria and held Genoa for a considerable time. They were not only redoubtable conquerors but lavish patrons of learning, arts, and sciences. They established colleges, public libraries, and scientific institutes. To the central scientific institute at Cairo[45] was attached a grand Lodge for initiating candidates into the esoteric doctrines of _Ismailism_.[46] This Lodge became the model of all the lodges created afterwards in Asia and Europe. Among the Druses of Lebanon who follow this cult, the sixth Fatimide Caliph, the eccentric al-Hakam, believed by them to be still alive, receives divine honours. With the death of the fourteenth sovereign of this house and the assumption of power in Egypt by Saladin[47] the Fatimide dynasty disappeared from the scene. =The Rise of Learning and Philosophy in Islâm.=—Even in the early days of the Caliphate, the pursuit of knowledge was not neglected at Medîna, and all the energies of the Moslem nation were not taken up in the struggle in which they had become involved with the surrounding nations. The Caliph Ali lectured to large multitudes of people on various branches of learning. The sack of Medîna by the Ommeyades destroyed the primitive school. It was revived by Ali’s great-grandson, Jaafar the Trusty, who died in 765 A.C. He is the real founder of speculative philosophy among the Moslems. The thinkers and scholars who flourished later derived their inspiration from him. The Mutazalite or rationalistic school was founded by Wâsil, who died in 785 A.C. Mâmûn, the sixth Abbasside Caliph, was a strenuous upholder of his doctrines. =‘The Brothers of Purity.’=—Towards the close of the tenth century a body of thinkers, whose researches extended to every department of the human mind, and whose great aim was to introduce a spirit of eclecticism in Islâm, established a brotherhood of intellect, which was to embrace all men animated with the single purpose of promoting the moral and intellectual welfare of the nation. =The Crusades.=—The Crusades, which devastated Western Asia for two centuries, and inflicted untold miseries on the unfortunate people exposed to the merciless raids of the hordes of Europe who professed ‘the religion of peace,’ involved the Moslem nations in a life-and-death struggle, during which intellectual development came to a standstill.