laid down for him and devoted his life to murder. Thus by the lure of Paradise the Assassins enlisted instruments for their criminal work and established a system of organized murder on a basis of religious fervour. "'Nothing is true and all is allowed' was the ground of their secret doctrine, which, however, being imparted but to few and concealed under the veil of the most austere religionism and piety, restrained the mind under the yoke of blind obedience."[134] To the outside world all this remained a profound mystery; fidelity to Islam was proclaimed as the fundamental doctrine of the sect, and when the envoy of Sultan Sajar was sent to collect information on the religious beliefs of the Order he was met with the assurance: "We believe in the unity of God, and consider that only as true wisdom which accords with His word and the commands of the prophet." Von Hammer, answering the possible contention that, as in the case of the Templars and the Bavarian Illuminati, these methods of deception might be declared a calumny on the Order, points out that in the case of the Assassins no possible doubt existed, for their secret doctrines were eventually revealed by the leaders themselves, first by Hasan II, the third successor of Hasan Saba, and later by Jalal-ud-din Hasan, who publicly anathematized the founders of the sect and ordered the burning of the books that contained their designs against religion--a proceeding which, however, appears to have been a strategical manoeuvre for restoring confidence in the Order and enabling him to continue the work of subversion and crime. A veritable Reign of Terror was thus established throughout the East; the Rafiqs and Fadais "spread themselves in troops over the whole of Asia and darkened the face of the earth"; and "in the annals of the Assassins is found the chronological enumeration of celebrated men of all nations who have fallen the victims of the Ismailis, to the joy of their murderers and the sorrow of the world."[135] Inevitably this long and systematic indulgence in blood-lust recoiled on the heads of the leaders, and the Assassins, like the Terrorists of France, ended by turning on each other. The Old Man of the Mountain himself was murdered by his brother-in-law and his son Mohammed; Mohammed, in his turn, whilst "aiming at the life of his son Jalal-ud-din, was anticipated by him with poison, which murder was again avenged by poison," so that from "Hasan the Illuminator" down to the last of his line the Grand Masters fell by the hands of their next-of-kin, and "poison and the dagger prepared the grave which the Order had opened for so many."[136] Finally in 1250 the conquering hordes of the Mongol Mangu Khan swept away the dynasty of the Assassins.