The Isma‘ili movement is named after Isma‘il, the eldest son of the sixth Shi‘ite imam Ja‘far alSádiq (d. 765). Ja‘far believed that each new imam must be designated in advance by the incumbent imam , guided in his decision by divine inspiration. 1 In accordance with this conviction, he publicly declared Isma‘il to be his successor. It so happened that Isma‘il died before his father, throwing the pro-‘Alid party into confusion. How could an infallible and omniscient imam , who claimed to receive his knowledge directly from God, err in such a critical matter as designation? 2 After a brief period of soul-searching, the majority of the Shi‘ites turned to Ja‘far’s eldest surviving son, ‘Abdallah. However, he too died a few weeks after the nomination. As we have learned from the previous chapter, many, but not all, of the Shi‘ites then accepted Ja‘far’s other son, Músa al-Kázim, as the seventh imam . However, this solution turned out to be unacceptable to some members of the pro-‘Alid party, who believed in the infallibility of the nominating imam , in this case, Ja‘far al-Sádiq. Seven being a magic number in the Islamic tradition, some members of the Shi‘ite movement decided that Isma‘il’s apparent demise was a ruse on the part of God to conceal him from the hostile attention of the ‘Abbásid authorities, so that the grounds would be prepared by his partisans for his triumphal return as the rightly guided redeemer ( máhdi ) or the “riser” ( al-qá’im ). 3 His followers then expected him to redress the many wrongs of this world rewarding the faithful and punishing the miscreants.