| From: Thomas Hockey et al. (eds.). The Biographical Encyclopedia of Astronomers, Springer Reference. New York: Springer, 2007, pp. 570-572 |
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Courtesy of 
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Ibn Sīnā:
Abū ʿAlī al‐Ḥusayn ibn ʿAbdallāh ibn Sīnā
Sally P. Ragep
Alternate
names
Avicenna
Died Hamadhān
(Iran), 1037
Ibn
Sīnā, also known as Avicenna, is renowned for his great works in
philosophy and medicine. He was also interested in the mathematical sciences,
and he dealt with a number of problems related to astronomy and cosmology
that had an impact on later astronomical work in Islamic regions and in Europe.
Ibn
Sīnā lived a full and colorful life and left an autobiography that
was completed by his associate Abū ʿUbayd
al-Jūzjānī. Here we emphasize his astronomical career. Ibn Sīnā
lived in Bukhārā between 985 and 1005 where he studied Ptolemy's
Almagest at an early age, basically being self‐taught. It is
said that he had access to the library of Nūḥ
ibn Manṣūr (died: 997), which included many books by the “Ancients.”
Ibn Sīnā lived in Gurganj from 1005 to 1012 where he wrote Station
of the Earth. He then resided in Jurjān (1012–1014), and during that
brief period he wrote his Comprehensive Observations, a treatise on
the Correction of the Longitude of Jurjān, and his Summary
of the Almagest (which he probably later incorporated into al‐Shifāʾ,
his great philosophical encyclopedic work). It was here that Jūzjānī
began studying the Almagest with him. In 1014–1015, Ibn Sīnā
moved to Rayy and then on to Hamadhān (1015–1024), where he wrote several
parts of the Shifāʾ. He lived his final years in Iṣfahān, where he completed the final parts of the Shifāʾ,
including the Almagest, composed the Najāt (the abridgement
of the Shifāʾ that included logic, natural philosophy, and
theology), and wrote his treatise on Astronomical Instruments during
periods of observation for the ruler ʿAlā' al‐Dawla. After Ibn Sīnā's death, Jūzjānī
added supplemental treatises on astronomy and mathematics to his Najāt.
There are many astronomical works associated with Ibn Sīnā,
but nine can be identified as authentic, and these can be classified into
four general categories: summaries of Ptolemy's Almagest, works on
instruments and observational astronomy, philosophical and cosmological works,
and miscellaneous works.
| (1) |
Ibn Sīnā's Taḥrīr
al‐majisṭī
is an extensive summary of the Almagest. Composed in Jurjān
between 1012 and 1014, he later revised it, and it became Part 4 of
the mathematical section of the Shifāʾ. Two works of
Ibn Sīnā that are often treated as separate treatises but
are really part of the above work are:
|
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| (2) |
Ibn Sīnā's al‐Arṣād
al‐kulliyya (Comprehensive observations) was written in Jurjān
(between 1012 and 1014) for Abū Muḥammad al‐Shīrāzī
and incorporated by Jūzjānī into Ibn Sīnā's
Najāt after his death. This short work contains nine chapters
and was translated into Persian as Raṣadhā kullī in the Dānishnāmah‐i
ʿilāʾī. Ibn Sīnā
states that he wishes to “abridge the explication of the comprehensive
observations from which one learns the general principles regarding
the configuration of the orb and the calculation of the motions.” |
||||
| (3) |
Ibn Sīna wrote Maqāla
fī al‐ālāt al‐raṣadiyya
(Treatise on astronomical instruments) in Iṣfahān sometime between
1024 and 1037, during his period of observations for ʿAlā' al‐Dawla.
This work indicates a practical side to Ibn Sīnā's astronomical
interests and also demonstrates his interest in precision. |
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| (4) |
Fīṭūl
Jurjān ([Correction of the]
longitude of Jurjān) was written in Jurjān (1012–1014) and
dedicated to Zarrayn Kīs, daughter of Amīr Qābūs
(= Shams al‐Maʿālī).
It is not extant but is discussed by Bīrūnī
in his Taḥdīd
al‐amākin, disparaging Ibn Sīnā's abilities
in practical astronomy. |
||||
| (5) |
al‐Samāʾ
wa‐ʾl‐ʿālam (De caelo et mundo)
was written for Abū al‐Ḥusayn
Aḥmad al‐Sahlī [Suhaylī?].
Most likely, this is what later became the chapter of the same name
in the Shifāʾ. |
||||
| (6) |
Maqāla fī al‐ajrām
al‐samāwiyya (al‐ʿulwiyya) (Treatise on the celestial
bodies). Like (5), this work is written from the perspective of cosmology/natural
philosophy, not mathematical astronomy. |
||||
| (7) |
ʿIllat
qiyām al‐arḍ
fī ḥayyizihā
(fī wasaṭ
al‐samāʾ) (On the cause of the
Earth's remaining in its position [in the middle of the heavens] = Station
of the Earth). It was written in Gurganj (circa 1005–1012), and
dedicated to al‐Sahlī to whom al‐Samāʾ
wa‐ʾl‐ʿālam
is also dedicated. |
||||
| (8) |
Maqāla (Risāla) fī
ibṭāl ʿilm (aḥkām) al‐nujūm (Essay on the refutation of astrology) or Risāla
fī al‐radd ʿalā
al‐munajjimīn (Treatise replying to the astrologers).
This treatise attacks astrology and, along with his work on the categorization
of the sciences, demonstrates Ibn Sīnā's attempt to demarcate
astronomy from astrology. |
||||
| (9) |
Maqāla fī khawāṣṣ
khaṭṭ al‐istiwāʾ (Essay on the characteristics
of the Equator). This work is no longer extant but Ibn Sīnā's
position that the equatorial region is the most temperate is known from
his Canon on Medicine and from his critics, which included Bīrūnī,
Fakhr al‐Dīn al‐Rāzī, and Naṣīr al‐Dīn
al‐Ṭūsī. |
Some
of the works associated with Ibn Sīnā are misattributions, uncertain
works, or duplications (due to longer or slightly different titles). (For
details, see Ragep and Ragep.)
Ibn
Sīnā's astronomical knowledge and works may be viewed as less developed
than those of his contemporaries such as Ibn
al‐Haytham and Bīrūnī; nevertheless, he had an
impact upon later writers, and several general points can be made about his
astronomical work.
First,
Ibn Sīnā shows a remarkable interest in observational astronomy.
Later writers refer to his observation of a Venus transit of the Sun, when
it was seen as a mark on its face. This helped him establish that Venus was,
at least sometimes, below the Sun. He also gave a new obliquity observation
of 23;33,30° and provided a new longitude distance for Jurjān, from Baghdad,
of 9;20° (compared with the traditional value of 8;0° and the modern value
of 10;3°). Ibn Sīnā's treatise on instruments includes a description
of a large instrument with an improved sighting system that theoretically
could provide considerably improved accuracy. Also, his summaries tend to
emphasize the role of observation. Noteworthy as well are Ibn Sīnā's
criticisms of the poor instruments and observations of Ptolemy and Hipparchus.
Second,
Ibn Sīnā's cosmological writings are more within the tradition of
natural philosophy rather than mathematical astronomy, and there is no extant
work (and none reported) that one could call a hayʾa work (i.e.,
one that provided a physical account of the mathematical models of the Almagest).
One can therefore understand his concern with the dynamics of celestial motion
and his reliance on natural philosophy to criticize Ptolemy's attempt to rely
strictly upon empirical evidence to disprove the possible rotation of the
Earth. He is also aware of violations of the accepted physics in Ptolemy's
models as well as the need for reforming the Ptolemaic system and reconciling
physics with mathematical astronomy.
Finally,
Ibn Sīnā plays a significant role in redefining and recategorizing
astronomy. He demarcates exact mathematical astronomy (ʿilm
al‐hayʾa) from astrology, which he views as being part of natural
philosophy.
Selected References
Dānish‐pazhūh, Muḥammad
Taqī (1985). Al‐Najāt min al‐gharq fī baḥr al‐dalālāt. Tehran: Dānešgāh‐e
Tehrān.
Gohlman, William
E. (1974). The Life of Ibn Sīnā: A Critical Edition and Annotated Translation.
Albany: State University of New York Press.
Ibn
Sīnā, Abū
ʿAlī al‐Ḥusayn
ibn ʿAbdallāh (1969).
Al‐Shifāʾ.
Al‐Samāʾ wa‐ʾl‐ʿālam
(Part 2 of Natural Philosophy), edited by Maḥmūd
Qāsim. Cairo.
——— (1980). Al‐Shifāʾ. ʿIlm al‐hayʾa (Part 4 of Mathematics
[al‐Riyāḍiyyāt]), edited
by Muḥammad Madwar
and Imām Ibrāhīm
Aḥmad. Cairo.
Mehren, A.
F. Von. (1884). “Vues d'Avicenne sur l'astrologie et sur le rapport de la
responsabilité humaine avec le destin.” Muséon 3: 382–403.
Ragep, F. Jamil
and Sally P. Ragep (2004). “The Astronomical and Cosmological Works
of Ibn Sīnā:
Some Preliminary Remarks.” In Sciences,
techniques et instruments dans le monde iranien (Xe– XIXe siècle),
edited by N. Pourjavady and Ž. Vesel, pp. 3–15. Actes du colloque tenu à l'Université
de Téhéran (7–9 juin 1998). Tehran.
Renaud, Michel
(1973). “Le ‘De celo et mundo’ d'Avicenne.” Bulletin de philosophie
médiévale 15: 92–130.
Saliba, George
(1980). “Ibn Sīnā
and Abū ʿUbayd al‐Jūzjānī:
The Problem of the Ptolemaic Equant.” Journal
for the History of Arabic Science 4: 376–403. (Reprinted in Saliba,
A History of Arabic Astronomy. New York: New York University Press,
1994, pp. 85–112.)
Wiedemann, Eilhard (1925). “Über
ein von Ibn
Sînâ (Avicenna) hergestelltes
Beobachtungsinstrument.” Zeitschrift
für Instrumentenkunde
45: 269–275. (Reprinted in Wiedemann, Gesammelte Schriften zur arabisch‐islamischen Wissenschaftsgeschichte. Frankfurt am
Main, 1984, Vol. 2, pp. 1110–1116.)
Wiedemann,
Eilhard and Th. W. Juynboll
(1927).
“Avicennas Schrift über ein von ihm
ersonnenes Beobachtungsinstrument.”
Acta orientalia
11, no. 5: 81–167. (Reprinted in Wiedemann, Gesammelte Schriften zur arabisch‐islamischen Wissenschaftsgeschichte. Frankfurt am
Main, 1984, Vol. 2, pp. 1117–1203.)