RARE annotated German translation of a selection of tales from the circle of Ikhwan as-Safa (The Brethren of Purity; also The Brethren of Sincerity) - a secret society of Muslim philosophers in Basra, Iraq, in the 8th or 10th century CE, with comprehensive introduction to the history and teachings of the society by the translator. The translator - Friedrich Heinrich Dieterici (1821-1903), was an eminent German orientalist and historian who translated many treatises of the Ikhwan as-Safa and Al-Farabi`s philosophical and psychological works into German, and authored many works in the field of Arabic philosophy and language study aids. 195x130mm. VIII+297 pages. Dark-blue cloth Hardcover with gilt lettering on spine. Cover corners/edges and spine edges rubbed. Spine bottom edge slightly bumped. Binding slightly visible between inner cover and whitepage. Front whitepage and title-page slightly fingerprint-stained. Pencil notes on rear whitepage. Front whitepage and two first pages edge slightly torn (3-5mm). Pages yellowing and slightly wavy. [SUMMARY]: This extremely rare German translation of excerpts from an influential medieval Encyclopedia of the Brethren of Purity (Rasa`il Ikhwan al-safa`) by the foremost authority in the field is in good condition.