| From: Thomas Hockey et al. (eds.). The Biographical Encyclopedia of Astronomers, Springer Reference. New York: Springer, 2007, pp. 356-357 |
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Fārābī: Abū
Naṣr
Muḥammad
ibn Muḥammad ibn Tarkhān al‐Fārābī
Alnoor Dhanani
Alternate
name
Alfarabius
Died Damascus, (Syria),
950
Fārābī
is mainly known as a philosopher, and his writings on the classification of
the sciences, including astronomy and astrology, were influential both in
the Islamic world and in Europe. Not much is known about Fārābī's
early years. He studied logic with the Nestorian Christian Yuḥannā ibn Ḥaylān
(died: circa 932) in Marw and then in Baghdad. In Baghdad, Fārābī
studied Arabic and was therefore able to participate in the philosophical
salons of Baghdad and to make use of Arabic philosophical and scientific works.
He then went to Constantinople with his teacher during the reign of the ʿAbbāsid
caliph al‐Muktafī (902–908) or early during the reign of Caliph
al‐Muqtadir (908–932). He returned to Baghdad between 910 and 920, spending
two decades there writing and teaching philosophy and allied sciences. In
942, Fārābī left Baghdad, probably to escape its instability,
going first to Damascus and then to Egypt. He later returned to Damascus to
join the court of the Ḥamdānid Prince Sayf al‐Dawla
but died a year later.
Fārābī
is known primarily for his contributions to Islamic philosophy; he was known
as “The Second Teacher” (al‐muʿallim
al‐thānī), the First Teacher being Aristotle.
His works include commentaries on Aristotle and Plato;
introductory philosophical works; treatises on logic, metaphysics, political
philosophy; and other philosophical disciplines; a treatise on the classification
of knowledge, and works in the mathematical sciences, which include astronomy
and music.
In The
Enumeration of the Sciences (Iḥṣāʾ al‐ʿulūm), Fārābī
discusses the place of astronomy within the classification of knowledge, its
subject matter, its demarcation from astrology, and its relationship with
mathematics. He there classifies knowledge broadly into the major divisions
of the linguistic sciences, logic, mathematics, physics, metaphysics, the
civic sciences of ethics and political philosophy, law, and theology. Mathematics
consists of seven branches: arithmetic, geometry, optics, astronomy, music,
statics (i. e., “the science of weights”), and technology. Astronomy,
or the “science of the stars” (ʿilm
al‐nujūm), consists of two parts. The first is astrology (ʿilm aḥkām al‐nujūm), which studies the signs of planets with regard to
their relationship with future events, and sometimes also present and past
events. The second part of astronomy is “mathematical astronomy” (ʿilm al‐nujūm
al‐taʿlīmī), which, unlike astrology,
is considered one of the mathematical sciences.
Mathematical
astronomy investigates celestial bodies and the Earth with regard to their
shapes, sizes, and distances; it investigates their motions, the components
of these motions, the calculation of positions of planets as a result of these
motions at any specific time, and the observable effects of motions, for example
eclipses and planetary risings and settings. Furthermore, it investigates
the inhabitable areas of the Earth, its climatic regions, and timekeeping,
i. e., seasonal hours. The determination that the Earth is entirely
at rest at the center of the Universe and that motions of celestial bodies
are spherical is made by mathematical astronomy.
Fārābī's
grounds for rejecting astrology are clear in two surviving works: On the
Utility of the Sciences and the Crafts (Risāla fī faḍīlat al‐ʿulūm
wa‐ʾl‐ṣināʿāt) and On the Aspects
in which Belief in Astrology Is Valid (Maqāla fī al‐jihāt
allatī taṣiḥḥu ʿalayhā
al‐qawl bi‐aḥkām al‐nujūm). Fārābī
acknowledges that celestial bodies have an effect on terrestrial bodies, but
he believes this effect to be mediated through the light radiated by the celestial
bodies. There is also a chain of causes from a particular position of a planet
to its eventual effect upon a particular terrestrial body. Therefore, one
is not dealing with a direct and necessary cause‐and‐effect relationship
between planetary position and an immediate terrestrial effect, but rather
with the relationship between a cause and its possible far‐removed and
remote effect. Any astrological prediction must take into account natural
and voluntary obstacles that may prevent the occurrence of the eventual effect.
Fārābī concludes that astrology is just conjecture, supposition,
smooth talk, and deception.
Fārābī's
philosophical cosmology was shaped by astronomy. He discusses the doctrine
of the ten intellects in his On the Opinions of the Inhabitants of the
Virtuous City (Kitāb arāʾ ahl al‐madīna al‐fāḍila).
The First Intellect necessarily emanates from the First Being, namely God.
Like the First Being, the First Intellect is immaterial. As it contemplates
the First Being, the First Intellect necessarily brings a third being, namely
the Second Intellect into existence. As it contemplates itself, the First
Intellect necessarily brings the celestial heaven into existence. The Second
Intellect also contemplates the First Being, which necessarily brings the
Third Intellect into existence. The Second Intellect's contemplation of itself
brings the sphere of fixed stars into existence. Similarly, the contemplation
of the Third Intellect brings the Fourth Intellect and the sphere of Saturn
into existence, the contemplation of the Fourth Intellect being brings the
Fifth Intellect and the sphere of Jupiter into existence, and so on through
the Tenth Intellect and the spheres of Mars, the Sun, Venus, Mercury, and
the Moon. Thus Fārābī combines Ptolemy's
planetary spheres with Neoplatonic emanationism and necessity into a philosophical
cosmology that would become the fundamental tenet of all subsequent Islamic
Hellenistic philosophers (falāsifa). In their view, the celestial
heavens were the realm of celestial intellects, souls, spheres, and planets.
Fārābī's
Commentary on Ptolemy's Almagest (Sharḥ al‐Majisṭī)
is his only strictly astronomical work. The text has not yet been edited,
but a Russian translation has been published, based on Ibn
Sīnā's shortened
recension preserved in a British Library manuscript.
Selected References
Druart, Thérèse‐Anne (1978). “Astronomie et astrologie
selon Farabi.” Bulletin
de philosophie médiévale 20:
43–47.
———
(1979). “La second traité de Farabi sur la validité des affirmations basées
sur la position des étoiles.”Bulletin de philosophie médiévale 21:
47–51.
Al‐
Fārābī, Abū Nasr (1948). Risāla fī fadīlat
al‐ʿulūm
wa‐ʾl‐sināʿāt. Hyderabad:
Dāʾirat al‐Maʿārif.
———
(1949). Iḥṣāʾ al‐ʿulūm, edited
by ʿUthmān Amīn. Cairo.
——— (1969). Sharḥ al‐Majistī,
translated into Russian by A. Kubesova and B. Rosenfeld. Alma Ata: Nakau.
——— (1982). “Nukat
fīmā yaṣiḥḥu wa‐mā
lā yaṣiḥḥu min aḥkām al‐nujūm.”
In Alfārābī's philosophische Abhandlungen aus Londoner,
Leidener, und Berliner Handschriften, edited by Friedrich Dieterici, pp.
104–114. Osnabrück: Biblio Verlag.
——— (1985). Al‐Farabi
On the Perfect State (Mabādiʾ ārāʾ ahl al‐madīna
al‐fāḍila), edited and
translated by Richard Walzer. Oxford: Clarendon Press.
——— (1986). Kitāb
ārāʾ ahl al‐madīna al‐fāḍila, edited by
Y. Karam, J. Chlala, and A. Jaussen. Beirut: Librairie Orientale.
Sezgin,
Fuat (1978). Geschichte des arabischen Schrifttums. Vol. 6, Astronomie, pp. 195–196. Leiden: E. J. Brill.