degree of contact had they with the Mu'tazilites? With the founders of grammar, of alchemy, of law? That they were themselves the actual beginners of everything—and everything has been claimed for them—we may put down to legend. But one thing does stand fast. Just as al-Ma'mun combined the establishment of a great university at Baghdad with a favoring of the Alids, so the Fatimids in Cairo erected a great hall of science and threw all their influence and authority into the spreading and extending of knowledge. This institution seems to have been a combination of free public library and university, and was probably the gateway connecting between the inner circle of initiated Fatimid leaders and the outside, uninitiated world. We have already seen how unhappy were the external effects of the Shi'ite, and especially of the Fatimid, propaganda on the Muslim world. But from time to time we become aware of a deep undercurrent of scientific and philosophical labor and investigation accompanying that propaganda, and striving after knowledge and truth. It belongs to the life below the surface, which we can know only through its occasional outbursts. Some of these are given above; others will follow. The whole matter is obscure to the last degree, and dogmatic statements and explanations are not in place. It may be that it was only a natural drawing together on the part of all the different forces and movements that were under a ban and had to live in secrecy and stillness. It may be that the students of the new sciences passed over, simply through their studies and political despair—as has

often happened in our day—into different degrees of nihilism, or, at the other extreme, into a passionate searching for, and dependence on, some absolute guide, an infallible Imam. It may be that we have read wrongly the whole history of the Fatimid movement; that it was in reality a deeply laid and slowly ripened plan to bring the rule of the world into the control of a band of philosophers, whose task it was to be to rule the human race and gradually to educate it into self-rule; that they saw—these unknown devotees of science and truth—no other way of breaking down the barriers of Islam and setting free the spirits of men. A wild hypothesis! But in face of the real mystery no hypothesis can seem wild.

Closely allied with both al-Farabi and the Fatimids is the association known as the Sincere Brethren (Ikhwan as-safa). It existed at al-Basra in the middle of the fourth century of the Hijra during the breathing space which the free intellectual life enjoyed after the capture of Baghdad by the Buwayhids in 334. It will be remembered how that Persian dynasty was Shi'ite by creed and how it, for the time, completely clipped the claws of the orthodox and Sunnite Abbasid Khalifas. The only thing, thereafter, which heretics and philosophers had to fear was the enmity of the populace, but that seems to have been great enough. The Hanbalite mob of Baghdad had grown to be a thing of terror. It was, then, an educational campaign on which this new philosophy had to enter. Their programme was by means of clubs, propagating themselves and spreading over the country from al-Basra and Baghdad, to