Abu Ya'qub al-Sijistani

Abu Ya'qub al-Sijistani was first and foremost a member of the Ismaili underground mission - the da'wa, as it is known in Arabic - that operated in the Iranian province of Khurasan and Sijistan during the tenth century. His activities and the works he wrote must be seen in that context; he was a partisan of a specific religious and political cause that involved the restoration of Shi'ism as the dominant force in the Islamic world of the time.

In addition al-Sijistani was an important advocate of philosophical doctrines that drew heavily on a current of Neoplatonism then circulating in intellectual circles of various kinds in the major centers of Islamic scholarship. For the latter reason in general and for his clear attachment in his philosophical writings to a fairly pure form of this branch of ancient thought, he earned an important place in the history of philosophy, even though he himself would have insisted that he was not a philosopher.