Hassan’s ambition was active from the earliest; while in that Nishapur school he bound both his classmates by a promise. Nizam ul Mulk himself tells the story: “‘Men believe,’ remarked Hassan one day to us, ‘that the pupils of our master are sure to be fortunate; let us promise that should success visit one of us only, that favored one will share with the other two.’ We promised.” Years later when Nizam ul Mulk was grand vizir to Alp Arslan, Sultan of the Seljuks, he showed Omar Khayyam sincere honor and friendship, and offered him the dignity of second vizir, which the poet rejected, but at his request the vizir gave him one thousand gold pieces each year instead of the office. Thenceforward Omar Khayyam was enabled to follow his bent and do great work, as astronomer and poet. Hassan Ben Sabah lived on in obscurity till the death of Alp Arslan in 1072. Nizam ul Mulk retained his high office with Melik Shah the new Sultan. Hassan Sabah went now to his friend and quoting bitter words from the Koran reproached him with forgetting sacred promises, and mentioned their agreement of school days. The vizir, who was kind, took his classmate to the sovereign and gained for him favor. Hassan Sabah, who had reproached his old friend out of perfidy, soon won great influence through cunning, feigned frankness and hypocrisy. In no long time Melik Shah called him frequently to his presence, advised with him, and followed his counsels. Soon Nizam ul Mulk was in danger of losing his office. Hassan had resolved to ruin his benefactor and classmate; in one word to supplant him. Each apparent omission of the great man was reported by tortuous ways to the sovereign, whose mind was brought to doubt the vizir, and to test him. The most painful blow of all, according to Nizam ul Mulk’s own statement, was given when Hassan promised to finish in forty days the whole budget of the Empire. Nizam ul Mulk needed ten times that period for the labor. Melik Shah gave all the men called for by Hassan, and with their aid the work was accomplished. But to defeat the vizir was not easy; Nizam ul Mulk had abstracted certain pages, hence Hassan’s budget was imperfect. He could not explain why the pages were lacking, and he could not restore them, so he went on a sudden to Rayi and to Ispahan somewhat later. In the latter city he lived in concealment at the house of Abu Fazl, the mayor, whom he converted, and who became his most intimate adherent.