Flourished
(Iraq), circa 961–980
The
Ikhwān were a philosophical-religious group, consisting of several authors
who lived in Basra, Iraq, and collected their teaching in an encyclopedia
known as the Rasāʾil Ikhwān al-Ṣafāʾ (The Epistles of the Brethren
of Purity). Composed circa 980, it contains 51 epistles (a fifty-second
considered spurious) and is grouped into Four Sections: (I) mathematical
sciences; (II) physical sciences; (III) psychological and intellectual sciences;
and (IV) metaphysical and legal sciences. The book is propaedeutical, i.e.,
a program of teaching, in this case based mainly upon Ismāʿīlī, neo-Pythagorean,
and neo-Platonic doctrines, but drawing as well on other traditions existing
in the tenth century.
Astronomy is the subject of the third, sixteenth, and thirty-sixth epistles.
The third epistle of Section I is devoted to “Astronomy, viz. Astrology
and the Arrangement of the Orbs (tarkīb al-aflāk).” It begins by
providing a categorization of the “science of the stars” (ʿilm al-nujūm):
a) cosmography (hayʾa); b) astronomical table-making (zījes),
compiling of ephemeredes (taqwīm), and chronology (istikhrāj
al-tawārīkh); c) astrology (aḥkām al-nujūm). This is followed
by a brief exposition of the Ptolemaic system of spheres and planets, while
the remaining part of this section concerns astrology. This basic astronomical
knowledge is mainly intended to be in the service of historical astrology,
the theory of cycles based upon conjunctions, which was meant to legitimize
the political power of the Shīʿa Imāmat.
The sixteenth epistle (the second of Section II), which treats “The Sky
and the World” (al-samāʾ wa-ʾl-ʿālam/de caelo et de mundo), provides
additional information. It is mainly based upon the Ptolemaic system and
Aristotelian physics with eleven spheres/orbs including the Earth and the
atmosphere. In addition, the diameters of the planets are given. Finally,
the thirty-sixth epistle (the fifth of Section III) is devoted to “Revolutions
and Cycles” (Fī al-adwār wa-ʾl- akwār) and is again mainly astrological
but with some passages of astronomical interest (cf. de Callataÿ 1996).
Marquet (1973, chap. 4) extensively discusses the celestial realm as presented
in the Rasāʾil.
This encyclopedia was translated into Persian, probably at the beginning
of the thirteenth century, in an extremely abridged form entitled The
Compendium of Wisdom (Mujmal al-ḥikma, the oldest copy dating
from 1268–1269); it was later apparently also dedicated to Tīmūr (died:
1405). This version follows the original plan and contents (I. ḥikmiyyāt;
II. ṭabīʿiyyāt; III. nafsāniyyāt; IV. ilāhiyyāt)
and maintains technical terms in Arabic.
Selected References
Bausani, Alessandro (1978).
L’enciclopedia dei Fratelli della Purità. Naples.
Diwald, Susanne (1975). Arabische
Philosophie und Wissenschaft in der Enzyklopädie “Kitāb Iḫwān as-Ṣafāʾ.”
(III) Die Lehre von Seele und Intellekt. Wiesbaden: O. Harrassowitz.
Fakhry, Majid (1983). A History of Islamic Philosophy. 2d ed. New
York: Columbia University Press, chap. 5.
Ikhwān al-Ṣafāʾ (1957). Rasāʾil Ikhwān al-Ṣafāʾ wa khullān al-wafāʾ.
4 vols. Beirut: Dār Ṣādir.
——— (1996). Les révolutions et les cycles: Epîtres des Frères de la
Pureté, XXXVI. Edited and translated by G. de Callataÿ. Louvain-la-Neuve.
——— (1375 H. Sh./1996). Mujmal al-ḥikma: tarjamah-i gūnahʾi kuhan āz
“Rasāʾil-i Ikhwān al-Ṣafāʾ.” An Abridged Persian Translation of “Rasāʾil-i
Ikhwān al-Ṣafāʾ.” Edited by I. Afshār and M. T. Dānishpazhūh. Tehran.
Marquet, Yves (1971). “Ikhwān al-Ṣafāʾ.” In Encyclopaedia of Islam.
2d ed. Vol. 3, pp. 1071–1076. Leiden: E. J. Brill.
——— (1973). La philosophie des Iḫwān al-Ṣafāʾ. Algiers.
Nasr, Seyyed Hossein (1964). An Introduction to Islamic Cosmological
Doctrines: Conceptions of Nature and Methods Used for its Study by the Ikhwān
al-Ṣafāʾ, al-Bīrūnī, and Ibn Sīnā. Cambridge: Harvard University Press.