Ikhwan al-safa is the name under which the authors of this work concealed their identity. The generally accepted translation of the work is the Epistles of the Brethren of Purity, those united by the purity of their souls and their loyalty to one another and to the true imam. The identity of the brethren seems still to be unclear, but the best known of them were Abu Sulayman Muhammad ibn Mush'ir al-Busti, Abu-l-Hasan 'Ali ibn Harun al-Zanjani, Muhammad ibn Ahmad al-Nahrajuri, Abu-l-Hasan al-'Awfi and Zayd ibn Rifa'a. They worked in Basra, Baghdad, Nishapur and Samarkand in the 10th century. The epistles represent the true state of Isma'ili doctrine at the time of their composition. See Encyclopaedia of Islam, III, pp. 1071-76 for a full discussion of the group and their ideas.
This is a very clean, beautifully copied manuscript.
For another copy of this work sold in these rooms, October 1997, lot 84.