ABSTRACT
The Isma'ilis split off from the rest of the Imami Shi'is on the death of the Imam Ja 'far al-Sadiq in 148/765; other Imami groups were eventually consolidated in terms of the Twelver community. Al-Qadi al-Nu 'man was also the founder of a distinguished family of judges in the Fatimid state. His son Abu'l-Hasan 'Ali, chief judge under al-'Aziz for nine years, was in fact the first person to bear the official title of qadi al-qudat, or the supreme judge in the Fatimid state. In codifying Isma 'ili law, al-Qadi al-Nu 'man drew on a variety of Shi 'i as well as Sunni sources, in addition to acknowledging the minoritarian position of the Isma 'ilis within the Fatimid state. The Isma'ili system of jurisprudence is almost exclusively the work of al-Qadi al-Nu'an, whose works have been preserved by the Tayyibi Isma'ilis of Yemen and South Asia.
