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Brethren of Sincerity, Epistles of


BRETHREN OF SINCERITY, EPISTLES OF (Arab. Ikhwān al-ṯafā'), series of Arabic treatises ostensibly covering the spectrum of philosophic studies: mathematics and logic, the natural sciences, metaphysics, and the political and religious organization of society including a discussion of the nature and organization of the "Sincere Brethren." The authors of the work were a group of people belonging to the class of government secretaries and men of letters in 10th-century *Baghdad. They were connected with the Ismāʿīliyya movement which opposed the claims of the reigning *Abbasid caliphs. Their treatises or epistles no doubt also served to propagate their political and religious ideas under the cloak of a philosophic encyclopedia. The level of learning set forth in the encyclopedia is popular and its philosophy is essentially neoplatonic, in contradistinction to the purer Aristotelianism preferred by, e.g., al-*Fārābī. Their writings seem to have influenced a number of Jewish philosophers, notably Joseph ibn *Ẓaddik and Solomon ibn *Gabirol as well as Moses *ibn Ezra. Shem Tov Ibn *Falaquera translated excerpts from their writings in his Sefer ha-Mevakkesh (1778). In Arles (1316) *Kalonymus b. Kalonymus translated a treatise of the Epistles into Hebrew under the title Iggeret Baʿalei Ḥayyim ("The Epistle of the Animals"). It has been printed a number of times and the Hebrew version has been translated into Yiddish and Ladino.


Steinschneider, Uebersetzungen, 860–2; D. Kaufmann, Geschichte der Attributenlehre (1877, repr. 1967); Vajda, in: Archives d'histoire doctrinale et littéraire du moyen-âge, 24 (1949), 114 and passim; Stern, in: Islamic Studies, 3 (1964), 405–28. add. bibliography: "Ikhwān al-Ṣafā'," in: eis2, 3, s.v. (incl. bibl.).

[Lawrence V. Berman]

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