Arabic Astronomy And Astrology

ANCIENT AND CLASSICAL SCIENCES AND PHILOSOPHY
LES DOCTRINES DE LA SCIENCE
DE L'ANTIQUITE AL'AGE CLASSIQUE
EDI'rEPAR
Roshdi RASHED et Joel BIARD
PEETERS
1999

ASTRONOMY AND ASTROLOGY IN MEDIEVAL
.ARABIC THOUGHT
George SALIBA
In this paper I attempt to document the conceptual distinction made
during medieval Islamic times between the science of astrology and that
of astronomy. This distinction is important in light of the fact that to
most people studying the history of Islam the two disciplines are thought
to be identical. Those people even attempt to explain the rise of early
Arabic astronomy as having been motivated by practical astrological
considerations1.
What I will attempt to do is to establish the distinction between those
two disciplines as it can be gleaned from the following types of sources.
I will first isolate the distinction commonly accepted in the Greek
sources of antiquity. Then I will discuss the reflection of that distinction
in the early Arabic sources, and follow up the developments in the tech-
nical texts dealing with the two disciplines in later medieval times. Then
I will tum to the non-technical texts in order to assess the social percep-
tion of these two disciplines, thus hoping to determine their social status
and thereby assess their place within the general framework of the
sciences.
ASTROLOGY/ASTRONOMY IN THE GREEK SOURCES
In order to illustrate the distinction between astrology and astronomy,
I would like to refer to the introductions of Ptolemy's books on these
subjects. In the Almagest, Ptolemy claims that he was following Aristotle
in dividing the sciences into theoretical and practical disciplines2. Of the
theoretical disciplines, namely metaphysics, physics and mathematics,
he distinguishes the mathematical sciences as the only ones that do not
1 See, for example, E. S. Kennedy, "The Arabic Heritage in the Exact Sciences", Al-
ａ｢ｾｩｩｴｨＬ＠ 23 (1970), p. 327-344, esp. p. 329, and Seyyed Hossein Nasr, An Introduction of
Islamic Cosmological Doctrines, Shambala, Boulder, 1978, p. 75. The most recent echo
of this attitude is to be found in Albert Hourani, A History of the Arab Peoples, Belknap
Press, Cambridge (Mass.), 1991, p. 76.
2 See Ptolemy, The Almagest, Ms. B.N. Tunisia, No. 7116, fol. P, tr. G. Toomer,
Springer, NY, 1984, p. 35.

132 G. SALIBA
depend on guessing, in contradistinction to metaphysics whose subject
cannot be known with certainty for "it cannot be seen nor could it be
comprehended3", and physics whose subject is the elements that are con-
tinually changing and regarding which the philosophers (l:zukama') are
never in agreement. Only the mathematical sciences are capable of giv-
ing certain and.unchanging knowledge to those who pursue them in ear-
nest, just because the proofs in those sciences are demonstrative and do
not allow any doubt for they involve numbers and geometric entities. Of
the mathematical sciences themselves, astronomy, the subject of the
book, is the highest, for, according to Ptolemy, it deals with the eternal
unchanging motions of the celestial bodies. He then goes on to say that
in that capacity astronomy serves the remaining two disciplines.
In the Tetrabiblos, the discipline of astrology is spoken of in relation
to astronomy in the following terms4
• Ptolemy admits outright that of the
two "means of prediction (7tpoyvounK<'>V) through astronomy", only
the first, i.e. astronomy, is both of higher rank and effective. Moreover,
astronomy is "desirable in itself even though it does not attain the result
given by its combination with the second5". He goes on to claim that it
was expounded by the "method of demonstration" in a separate treatise,
i.e. the Almagest. In the Tetrabiblos, he intended to give an account of
the
second and less-sufficient method in a properly philosophical way, so that
one whose aim is the truth might never compare its perceptions with the
sureness of the first, unvarying science, for he ascribes to it the weakness
and unpredictability of material qualities found in individual things, nor yet
refrain from such investigation as is within the bounds of possibility, when
it is so evident that most events of a general nature draw their causes from
the enveloping heavens6•
In specifying the distinction further, he goes on to say:
But since everything that is hard to attain is easily assailed by the general-
ity of men, and in the case of the two before-mentioned disciplines the alle-
gations against the first could be made only by the blind, while there are
specious grounds for those leveled at the second - for its difficulty in parts
has made them think it completely incomprehensible, or the difficulty of
escaping what is known has disparaged even its object as useless - we shall
3
Almagest, fol. 2'.
4
Ptolemy, Tetrabiblos, ed. & tr. by F. E. Robbins, Loeb Series, Harvard, Cambridge
(Mass.), 1940, p. 3.
5 Ibid.
6 Ibid., p. 3-5.
ASTRONOMY AND ASTROLOGY 133
try to examine briefly the measure of both the possibility and the useful-
ness of such prognostication before offering detailed instruction on the sub-
ject?.
Indeed the next two chapters of the Tetrabiblos are devoted to the sub-
ject of the possibility and the utility of astrology.
In the first of the two Ptolemy admits that astrology is difficult to
master, and because of that people have less confidence in it. But he
goes on to say:
If, then, a man knows accurately the movements of all the stars, the sun, and
the moon, so that neither the place nor the time of any of their configurations
escapes his notice, and if he has distinguished in general their natures as the re-
sult of previous continued study, even though he may discern, not their essential,
but only their potentially effective qualities, such as the sun's heating and the
moon's moistening, and so on with the rest; and if he is capable of determining
in view of all these data, both scientifically and by successful conjecture, the
distinctive mark of quality resulting from the combination of all the factors,
what is to prevent him from being able to tell on each given occasion the charac-
teristics of the air from the relations of the phenomena at the time, for instance,
that it will- be warmer or wetter? Why can he not, too, with respect to an indi-
vidual man, perceive the general quality of his temperament from the ambient at
the time of his birth, as for instance that he is such and such in body and such
and such in soul, and predict occasional events, by use of the fact that such and
such ambient is attuned to such and such a temperament and is favorable to
prosperity, while another is not so attuned and conduces to injury8?
He goes on to defend astrology against its possible detractors by
pointing out that the difficulty of attaining it should not be considered as
sufficient grounds to condemning it.
At the end of this chapter he counsels that we should not
gropingly and in human fashion demand everything of the art, but rather
join in the appreciation of its beauty, even in instances wherein it could not
provide the full answer; and as we do not find fault with the physicians,
when they examine a person, for speaking both about the sickness itself
and about the patient's idiosyncrasy, so too in this case we should not ob-
ject to astrologers using as a basis for calculation nationality, country, and
rearing, or any other already existing accidental qualities9
•
From a theoretical point of view, it is clear to anyone reading those
two characterizations of the two disciplines that Ptolemy did hold
7
Ibid., p. 5.
8 Ibid., p. 11-13.
9
Ibid., p. 19.

134 G. SALffiA
astronomy in a much higher esteem than astrology. At the same time,
however, he felt that astronomy was somehow incomplete, and that it
would be completed only when it was combined with astrology.
Astrology, on the other hand, was "less-sufficient" and involved many
variables, a good number of which had to depend on "previous
continued study", i.e. experience. Just like medicine and piloting it
involves a good amount of conjecture. Its mastery, however, was never-
theless possible, only in theory.
ARABIC TECHNICAL SOURCES
The earliest Arabic technical treatise touching on the subject of the
distinction between astrology and astronomy that I know of is Abu
Ma'shar al-Balkhl's great introduction to astrology, which was written
during the first part of the ninth century10
• We first note that Abu
Ma'shar calls his book the Great Introduction to the Science ofthe Judg-
ments ofthe Stars, which simply adds a new dimension to the Ptolemaic
distinction by isolating astrology not as simply a method of astronomical
prognostication but that it involves some kind of a decree issued by the
stars. The first treatise of the Great Introduction, composed of six chap-
ters, is the best well argued case for the validity of astrology, and the
manner in which such a discipline can be perceived from the Aristotelian
perspective. Needless to say, AbU Ma'shar makes full use of the Aristote-
lian doctrines regarding the attribution of the phenomena of generation
and corruption to the movement of the stars. That doctrine in specific is
very well argued by Abu Ma'shar in chapter three of the first treatise,
which is titled "On the Manner in Which the Planets Affect this
World"11 •
Two other chapters are much more interesting for our purposes here,
for they draw a much clearer distinction between astrology and as-
tronomy. In chapter two of the first treatise12, Abu Ma'shar argues thus:
There are two magnificent and marvelous types of science (naw'ayn min
al-'ilm 'afibayn fi al-fikra Ｇ｡ｾｦｭ｡ｹｮ＠ fi al-qadar). The first is called the
1
0 This text was first published in a facsimile reproduction of a manuscript ｫｾｰｴ＠ in
Istanbul, Carullah 1508, with a new pagination, by F. Sezgin, as The Great Introduction to
the Science ofAstrology, Frankfurt, 1985. For the edition and translation see .R. Lemay,
Liber Introductorii Maioris ad Scientiam Judiciorum Astrorum, 9 vols., Napoh, 1995.
11
Ibid., p. 38-46.
12
Ibid., p. 17-38.
universal science ('ilm al-kull), and it deals with all the subjects dealt
with in the great book of the wise Ptolemy, namely the Almagest. Here
Abu Ma'shar follows Ptolemy in asserting that in the first science, i.e.
astronomy, it is the method of proof which depends on arithmetic, geom-
etry and surveying which gives the discipline the certainty it enjoys. At
this stage, i.e. the early part of the ninth century, Abu Ma'shar does not
yet use the more familiar term for this science, 'ilm al-hay'a, which we
will meet later on.·
The concept of a universal science ('ilm al-kull) as applied to as-
tronomy by Abu Ma'shar should be understood in contrast to astrology,
in the sense that astronomy determines the general universal principles,
while astrology determines the particulars. By the universal principles,
one should understand such principles as periods of motion, relationship
of one planet to another, etc., as the unchanging eternal principles. The
more particular principles of change, which fall within the domain of
astrology, should also be understood in the Aristotelian sense of change
from one state to another. In fact, Abu Ma'shar himself gives the exam-
ple of the emission of smoke from the burning wood under the action of
fire as the type of change intended in which the smoke which was poten-
tially in the wood is brought out in actuality through the action of fire.
Similarly, since the planets move continuously in a uniform circular
motion they generate the kind of fire that is responsible for bringing out
the process of change in the sublunar region from the potential to the
actual state. This approach, which is obviously a simplified version of
the Aristotelian doctrines expressed in the Generation and Corruption13,
De Caelo1
4, and in the Generation of Animals15, is argued in chapter
three of the first treatise. We should only note that it stresses the physical
aspect of astrology, rather than the geometric mathematical aspect. Abu
Ma'shar does not say that change in the sublunar region takes place on
account of the positions of the planets, their aspects with respect to one
another and with respect to the local horizon as he will argue later, rather
he limits himself at this point to stressing the physical aspect of the gen-
erating fire (not the destructive fire) as the agent that would bring about
change.
As for the definition of the science of astrology itself, Abu Ma'shar
states it in the following terms:
13
II, 10, 336 a.
14 II, 286 a 3 - 286 a 10.
15
IV, 10, 777 b 16 - 778 a 10.

136 G. SALffiA
The science of the decrees [of the stars ('ilm ｡ｬＭ｡ｾｫ｡ｭＩ｝＠ is the science in
which one knows the nature of each planet and sphere, and their particular
indications ＨｫｨｩｩｾＣｹ｡ｴ＠ daliilatihii) regarding that which is generated in this
world, below the sphere of the moon, by the forces of their motions and
natures16•
In chapter two of the third treatise, Abu Ma'shar returns to the defini-
tion of the science of astrology, and reformulates the definition of the
science of astrology in a more formal language by saying: "The defini-
tion of the science of the decrees [of the stars] is the knowledge of the
indications of the forces of the motions of the planets at a specific time,
as well as a future appointed time"17• In this new definition, we note that
he obviously changes two important concepts. Here he stresses the mo-
tion of the planets only, and drops the reference to the natures of the
planets, which he had mentioned earlier. Secondly, he inserts the possi-
bility of determining future events as part of the scope of astrology. It is
the latter addition which was perceived by the religious scholars to be
specially objectionable for it claims for the astrologer the kind of knowl-
edge that even prophets did not always have, namely the knowledge of
future events.
The fact that Abu Ma'shar seems to be following Ptolemy in regard to
the distinction drawn between astronomy and astrology should not mis-
lead us to think that he agrees with Ptolemy on all details of astrology. In
the first chapter of the fourth treatise, for example, he takes Ptolemy to
task on the issue of the characterization of the planets in a language that
could be understood to mean that the planets share some of the proper-
ties of the elements in the sublunar region18. As far as the general dis-
tinction between the two sciences, he does not find himself in disagree-
ment with Ptolemy.
Similar distinctions between astrology and astronomy are found in
later treatises on astronomy and astrology, as well as in the works which
were devoted to the classification and enumeration of the sciences.
Someone like Biriini writes in the tenth century that he had full confi-
dence in the certainty that one could derive from astronomy, but had
very little faith in the science of astrology19
• He draws a clear distinction
16
Treatise /, chapter 2, p. 18.
17
Great Introduction, p. 146.
18
Ibid., p. 210.
19 Abii al-Rayl,liin al-Biriini, Kittib al-Tajhlm li-Awti'il fiinti'at al-Tanjlm (The Book of
Instruction in the Elements ofthe Art ofAstrology), tr. by R. Ramsey Wright, Luzac, Lon-
don, 1934, p. 210.
between the two sciences and even discusses the etymological distinc-
tion between the astrology and astronomy. That distinction was the sub-
ject of a study by Shlomo Pines20
•
When it comes to the specific terms used to designate each of the two
sciences, the Greek tradition is not very helpful, for it either groups both
disciplines under the term astronomy, which is in tum seen as a math-
ematical discipline, or it does not employ different terminology in order
to distinguish betwe.en the two as was done by Ptolemy when he referred
to both disciplines in the Tetrabiblos as two different methods of astro-
nomical prognostications.
As far as I can tell, it was not until Islamic times that we begin to
note clear terminological distinctions between the two disciplines. We
have just mentioned the use of the term 'ilm al-kull to refer to astron-
omy, versus 'ilm al-a/:tkam to refer to astrology as they were used by
Abu Ma'shar in the first half of the ninth century. Other contempora-
ries of Abu Ma'shar, who worked mainly in astronomy would refer to
their discipline as 'ilm al-hay'a, to mean something neutral as the
Science of the Configuration [of the Celestial Spheres], while the as-
trologers continued to use 'ilm al-aJ:tkam (Science of the Decrees) or 'ilm
aJ:tkam al-nujum (Science of the Decrees of the Stars). Unfortunately
very few of their texts have survived, and we are basing our judgment
mainly on the surviving titles of their works. We note, for example,
that the famous Mul:lammad b. Musa al-Khwarizmi was referred to by
the author of the Fihrist, who wrote during the second half of the tenth
century, as being from among the astronomers (min ｡ｾｊＺｵＧｩ｢＠ 'ulum al-
hay'a), in order to distinguish his general work from the work of the
astrologers21
• Al-Nadim was obviously using the newly coined term
hay'a to designate astronomy proper. Other writers from the same period
had their works also designated as being hay'a texts such as Sahl b.
Bishr22
, 'Utarid b. Mul:lammad2
3, and Abu Ma'shar himself24. But this
could only be a designation used by al-Nadim who was writing during
the next century.
20 Isis, 55 (1964), p. 343-349.
21
Mul,larnrnad lbn Isl,laq al-Naorm, Kittib al-Fihrist, ed. R. Tajaddud, Teheran, 1971,
p. 333.
22
Ibid.
23
Ibid., p. 336, where the exact title is Kittib Tarklb al-Afltik (A Book on the Structure
of the Orbs).
24
Ibid., p. 336.

138 G. SALIDA
Of the surviving hay'a works from the ninth century, I only know of
the work of Qusta b. Liiqa which was apparently an astronomical text
called kitiib al-hay'a25• The works of others like Ibn Kathir al-Farghiini
were designated with various titles by the later bio-bibliographers.
Farghani's major summary of the Almagest, which has nothing to do
with astrology was designated by al-Naaun and al-Qifti among others as
kitiib al-fu$ul or ikhti$iir al-majis{i, U$Ul J:tarakiit al-nujum, 'ilm al-nujum
wa-l-J:tarakiit al-samiiwiya, or al-madkhal ilii 'ilm hay'at al-afliik wa-
J:tarakiit al-nujum26. At least one manuscript refers to it as kitiib al-
hay'a21, but this could be a later owners addition.
What is certain is that by the tenth century when al-Nadim was writ-
ing the term hay'a referred to astronomy proper, and aJ:tkiim referred to
astrology. Other authors from the tenth century, such as al-Farabi con-
firm this systematic distinction between astrology and astronomy. In fact
al-Farabi wrote a special treatise in which he attacked the science of
aJ:tkiim, and said nothing of astronomy. In his enumeration of the sci-
ences there is a clear distinction between the two sciences, but that
'
should be seen in the context of the general classification of the sciences
which had a long tradition in medieval Islam.
THE CLASSIFICATION OF THE SCIENCES
Fiiriibf28
In the enumeration of the sciences, Farabi refers to astronomy as part
of 'ilm al-nujum (science of the stars), which in his time was the general
term used for both astronomy and astrology. This does not mean how-
ever that he does not distinguish between the two disciplines. In his own
words:
As for 'ilm al-nujum, there are two sciences that are known with this name:
The first is the science of the decrees, which is the science of the indica-
tions of the stars regarding future events, and most of what is presently in
25 A copy of this text survives at the Bodleian Library, Oxford, Seld A.ll, mention.ed
with the wrong number in F. Sezgin, Geschichte des arabischen Schrifttums, Bnll,
Leiden, VI, 1978, p. 182.
26 Al-Nadim, Fihrist, p. 337, and al-Qi{!I, Ta'rfkh al-/fukamii', ed. J. Lippert, Leipzig,
1903, p. 286.
27
Paris, B.N. Arabe, 2504.3.
28 The text considered here is Abii ｎ｡ｾｲ＠ al-Fiiriibi, ｬｬ［ＮｾｩｩＧ＠ a/-'Ulum, ed. 'Uthrniin Arnin,
al-Maktabat ｡ｬＭａｮｧｬｯＭｍｩｾｲｩｹ｡Ｌ＠ Cairo, 1968.
existence or had already taken place. The second is the mathematical sci-
ence of the stars, which is considered among the sciences as well as among
the mathematical disciplines (yu'add fi al-'ulilm wa-fi al-ta'iilim). As for
the first [i.e. the science of the decrees] it is considered among the crafts
and the abilities through which one can forewarn of future evens like dream
interpretation, divination, augury and such powers. The mathematical
science of the stars investigates the celestial bodies and the earth in three
different areas [...]29•
He goes on to enumerate these areas by including the configuration of
the celestial bodies and their positions with respect to one another; the
motions of the celestial bodies; and the conditions of the earth regarding
the inhabited and the un-inhabited parts, and the conditions that take
place on the earth as a result of the celestial daily motions.
Although Farabi does not use a special term, like hay'a to designate
astronomy proper, he was definitely aware of the distinction between as-
tronomy and astrology. As was mentioned before, he even wrote a trea-
tise in which he argued against astrological prediction, whereby he sin-
gled out astrology as an unreliable discipline30• Furthermore, he admits
in that treatise that the confusion between astronomy and astrology is
due to the use of the same name to indicate either discipline, while in
reality astronomy (aJ:tkiim nujumiya tjaruriya) is a necessary mathemati-
cal science (J:tisiibiyiit wa-maqiidiriyiit) while astrology can only be
counted among the possible (mumkina) and the conjectural Ｈ｢ｩＭｬＭｾ｡ｮｮ＠
wa-l-watj} sciences.
His criticism of astrology is on the level that it is only a possible sci-
ence and not a necessary one, and thus could not be decided either way.
From a methodological point of view he also asserts the irrelevance of
experience in matters of astrology, for experience, he says; would be
useful only when the possible come to occur often and not rarely.
The treatise, as it reached us, is only a collection of notes, which were
copied down by some Abii Isl:taq Ibrahim 'Abdallah al-Baghdadi, and by
his own admission were not yet prepared by Farabi as an argument
against astrology. But despite their unconnected nature, their import in
refuting astrology as a reliable science is indeed very clear.
29 Ibid., p. 102-103.
30 The text which was edited by F. Dietrich in Al-Farabi's philosophische Abhand-
lungen aus Londoner, Leidner und Berliner Handschriften, Leiden 1890, under the title
Nukat fimii ｹ｡ｾｩｬ［Ｎｬ［Ｎｵ＠ wa-mii Iii ｹ｡ｾｩｬ［Ｎｬ［Ｎｵ＠ min al;.kiim al-nujiim. See also Therese-Anne
Druart, <<Astronomie et astrologie selon Farabi>>
, Bulletin de philosophie medievale,
Belgium, 1978, p. 43-47.

140 G. SALffiA
Al-Nadlm, AbU al-Faraj Mul:zammad b. Abl Ya'qub, Isf.uiq known as al-
Wamzq (c. 976), the author of al-FihrisP1
Although the second chapter of the seventh treatise of the Fihrist is
devoted to the biographies of the mathematicians, which include the
biographies of the astronomers/astrologers among them, one finds both
classes of scientists referred to as munajjimln, a term which should be
understood to mean those who study the science of the stars. But as we
have seen in the case of Farabi, the fact that both disciplines were re-
ferred to with the same name does not mean that the distinction between
the two was not clearly understood.
When referring to the biography of ｍｵｾ｡ｭｭ｡､＠ b. Musa al-Khwa-
rizmi, al-Nadim refers to him as "from among the astronomers (min
｡ｾｦＮｵｩ｢＠ 'ulum al-hay'a)"32; where the term hay'a is explicitly used to dis-
tinguish astronomy from astrology. Similarly, when he refers to Abu al-
'Abbas al-Nayrizi he says: "He is famous for the science of the stars
('ilm al-nujum), especially astronomy (siyyama fi 'ilm al-hay'a)"
3
3,
where he uses the term hay'a again as a subclass of the science of the
stars, and to designate with it astronomy proper.
Both of these references, i.e. that of al-Farabi and al-Naorm, indicate
that the two disciplines, astronomy and astrology, were first called with
the same name. But sometime towards the middle of the tenth century,
the name hay'a began to be used in a technical sense in order to desig-
nate astronomy proper.
Khwarizml, Abu 'Abdallah Mul:zammad b. AJ:zmad b. Yilsuf al-kiitib
(c. 997)
In the text, Mafatl/:z al-'ulum34, Khwarizmi who was writing towards
the end of the tenth century, designates astronomy with the independent
name 'ilm al-hay'a. But it is still subsumed under the general title 'ilm
al-nujum as an independent chapter together with three others35
• The fact
that astronomy is given a chapter by itself36
tends to confirm our hypoth-
esis that the separation must have taken place on the formal level to-
wards the end of that century. Furthermore, Khwarizmi defines 'ilm al-
3! See supra, p. 137 n. 21.
32 Fihrist, p. 333.
33 Ibid., p. 337.
34 Edited by G. Van Vloten, Leiden, 1895.
35 Ibid., p. 209f.
36 Ibid., p. 215f.
nujum, as Arabic tanjlm, and Greek astronomia (acr'tpOVOJ.Lia), and
gives astronomy hay'a the second position immediately following the
names of the stars. Astrology is still referred to under the name al:zkiim,
and is treated in the third chapter.
Ibn Sinii (1037)
In the next century, Ibn Sina distinguishes the two disciplines in a
much more radical way. Astronomy (now called 'ilm al-hay'a) is no
longer subsumed under 'ilm al-nujum together with astrology, but now
has its own independent place among the mathematical sciences37• As-
trology, on the other hand, which continued to be called al:zkiim al-
nujum, is now classified under the branches of the physical sciences
together with medicine, dream interpretation, talismans, etc.
As far as astrology is concerned, Ibn Sina devoted a separate treatise
in order to attack it. That treatise was studied by A. F. Mehren38, and
need not be discussed here. But we should emphasize, that with Ibn
Sina, we begin to have a theoretical distinction between the two disci-
plines, and for the first time, I think, astrology is removed from its prox-
imity to astronomy to the realm of the physical sciences. Conceptually,
this is not trivial, for it strengthened astronomy as a mathematical disci-
pline, and condemned astrology to the realm of the uncertain physical
sciences. We shall soon see the repercussions of this re-organization on
the philosophical, religious thought which governed the treatment of
astrology.
Shams al-Din AbU 'Abdallah Mu}J.ammad b. Ibrahim b. Sa'id ｡ｬＭａｮｾ｡ｲｩ＠
al-Sinjari, known as Ibn al-Akfani (d. 1348)
In his influential classification of the sciences, which was heavily
quoted by those who came after him, Ibn al-Ak!ani continues this trend
and deepens the chasm between the two disciplines. In his Irshiid al-
ｑ｡ｾｩ､＠ ila Asna ｡ｬＭｍ｡ｱ｡ｾｩ､＠ (Guiding the Seeker to the Highest of
Aims)39, he keeps astrology ('ilm al:zkiim al-nujum) with the physical sci-
ences together with medicine, veterinary medicine, physiognomy and
dream interpretation40, but moves astronomy to head a list of a subgroup
37 Aqsiim al-'UIUm al-'Aqliya, al-Jawii'ib Press, Istanbul, 1298.
38
Le Museon, 3 (1884), p. 383-403.
39 Edited by Januarius Justus Witkam, Tet Lugt Pers, Leiden, 1989.
40 Ibid., p. 49 of Arabic text.

142 G. SALIBA
of sciences41 , thus placing it on equal footing with the physical sciences,
logic, metaphysics, etc. We should note that he has no separate section
for the mathematical sciences. Instead he lists each of geometry, as-
tronomy, arithmetic, and music as separate disciplines, each constituting
several others with the exception of music.
When discussing the science of astronomy ('ilm al-hay'a), he refers to
it in the following terms:
It is a science in which one knows the conditions of the simple superior and
inferior bodies as well as their forms, positions, magnitudes, the distances
among them, and the motions of the planets and the spheres and their
magnitudes. Its subject matter is the above mentioned bodies in regard to
their number, positions, and necessary motions. It is divided into four main
divisions: In the first, one investigates the totality of the spheres, their posi-
tions with respect to one another, their ratios, and the demonstration that
they move while the earth remains stationary. In the second, one investi-
gates the motions of the celestial spheres, the fact that they are all circular
[the text has kurlya = spherical], their number, their quality, which of them
are voluntary and which are by compulsion, their direction, the manner in
which one knows the position of each planet along the zodiacal signs at any
time, and the concomitant (lawiiiJiq) celestial motions such as eclipses and
the like. In the third, one investigates the inhabited and the uninhabited
parts of the earth, the division of the inhabited part into climes, the condi-
tions of the various localities and the concurrent daily motions pertaining to
them, and the risings and settings as well as the duration of days and
nights. In the fourth, one knows the magnitudes of the stars, their distances,
and the areas of their spheres.
Among the abridged books in this science is the Almagest of al-Abhari,
the medium size is the hay'a of Ibn Aflal:l, and the more detailed is the
Qiiniln al-Mas'ii.dl of Abii al-RayJ:!an al-Biriini and ShariJ al-Majistl of al-
Nayrizi. These books depend on the science of geometry because the intro-
ductions of their proofs are geometrical. As for the books that are free of
these [introductions], in which one is limited to the descriptive
conceptualization (ta$awwur) of these matters without confirmation
(ta$dlq), the abridged is the tadhkira of Khwaja ｎ｡ｾｉｲ＠ al-Din al-Tiisi, the
medium-size is the hay'a of 'UrQI, and the detailed is the Nihiiyat al-Idriik
of Qutb al-Shlrazi [...]42
•
He goes on to say that
the utility of this science in itself comes from the nobility of its subject
matter, the certainty of its proofs, and from the adoration of noble souls for
its organization and order and its perfection of illustration and demonstra-
tion. For that reason the Qur'an has urged people to seek it.
42 Ibid.
The science [of the stars] is divided by the religious scholars to obliga-
tory (wiijib), recommended (mandub), permissible (mubiiiJ), disapproved of
(makrilh) and forbidden Ｈｭ｡ｩｊｾｩｬｲＩＮ＠ Of these categories that part of as-
tronomy which relates to religious duties is obligatory. The recommended
is that portion which leads to the conviction concerning the existence of
God from observing the astronomical phenomena. Astrological doctrines
which assume the influence of the planets to be according to God's design
and not to the necessary powers of the planets are permissible. The forbid-
den is the belief ｴｾ｡ｴ＠ these effects are necessarily on account of the nature
of the planets themselves43•
I quoted this text at length on account of its historical importance. On
the one hand, it draws a clear distinction between astronomy and astrol-
ogy. And on the other hand, it defines astronomy in a much more elabo-
rate language than the preceding similar works. Moreover, it introduces
the element of the social acceptability of astronomy and the subtle dis-
tinction between the two types of astrology. It is significant that this sift-
ing process had already taken place by the middle of the fourteenth cen-
tury, and that one part of what used to be one science was developed on
its own to become an acceptable mathematical discipline, while the other
was sorted out and distinguished into two permissible and forbidden
sciences.
Earlier on, Ibn al-Akiani had given a general definition of science that
is of some interest here in regard to the distinction he draws between the
two types of astronomical works, namely those which contained descrip-
tive conceptualizations Ｈｴ｡ｾ｡ｷｷｵｲＩ＠ only, and those which had confirma-
tions Ｈｴ｡ｾ､ｩｱＩ＠ as well. In order to understand the full nuance of this text I
should quote Ibn al-Akiani once more. He says in the introductory chap-
ter of his treatise (al-qawl fi al-ta'lim wa-1-ta'allum wa-shurutihimii)44
:
Knowledge is either descriptive conceptualization (ta$awwur) or confirma-
tion (ta$dlq). Descriptive conceptualization is sought through explanatory
statements composed of definitions, illustrations, and the like. One could
comprehend the truth of something and could imagine its likeness. Confir-
mation, on the other hand, comes from certain things which are introduc-
tions to other things, which are in tum the forms of analogies for still other
things which are themselves conclusions that could produce certainty
(yaqln), or only conviction (iqnii}45
•
In this context we can better understand his distinction between the
two types of astronomical texts which he referred to. In fact, such texts
43
Ibid., p. 58 of Arabic text.
44
Ibid., begins p. 16 of Arabic text.
45
Ibid., p. 16 of Arabic text.

144 G. SALffiA
as Tfisl's tadhkira do not contain proofs that would lead to conviction as
Ibn. al-A.klanl would put it. They can only lead to descriptive
conceptualization. 'Urql's hay'a is similar to it, except it contains many
more proofs than the tadhkira, but not as many as the Almagest. Shirazi's
text is still more elaborate, and contains still more proofs. But Ibn al-
A.klanl is right in considering this class of texts to be different from
Blrfinl's Qaniin, or the Almagest, or Ibn Aflal:t's hay'a. But the fact that
the first group of texts does not contain proofs, does not mean that those
proofs are beyond the reach of those astronomers. In fact, the descriptive
conceptualizations that they offer could be easily proven. Their purpose
was to assume that one understands such texts as the Almagest, and what
they wished to do was to correct the conceptual scheme of the Almagest,
leaving everything else, including the proofs, intact. In that sense those
texts go a step beyond the text of the Almagest.
TaskUpriizadeh, ａｾｭ｡､＠ b. ｍｵｾｴ｡ｦ｡＠ (1495-1561)46
Taskiipriizadeh follows Ibn al-Akflinl very closely. He keeps astrology
under the physical sciences, but reconsiders astronomy as part of the
mathematical sciences for which he has a short introductory note. Then
in two separate chapters he treats astronomy as a discipline: in the first
he summarizes the text of Ibn al-A.klant47
, and then in a separate chapter
he gives the subdivisions of astronomy48
•
From an epistemological point of view, Taskiipriizadeh does not add
anything to the already existing dichotomy between astrology and as-
tronomy. One can simply assume that the division, apparently started by
Ibn Slna between astrology, as a physical science, and astronomy, as a
mathematical science continued to be developed after Ibn Slna.
Tahanawi, ｍｵｾ｡ｭｭ｡､ａ＠ 'Ia b. 'Ali (after 1745)
In his famous encyclopedia, Kashshaf ｉｾｴｩｬ｡ｾ｡ｴ＠ al-Funiin49
, Tahanawl
gives a detailed account of the scientific concepts and their relationships
to one another. In the introduction of that work he gives his own expla-
46 Miftiil; al-Sa'iida wa-mi$biil; al-siyiida fi maw.;iu'iit al-'ulum, ｾ､Ｎ＠ by Kamil Kfunil
Bakrl and 'Abd al-Wahhab Abu ai-Nur, Dar ai-Kutub al-l:laditha, Carro, 1968.
47 Ibid., p. 372-373.
48 Ibid., p. 379-389.
49 First published in Bibliotheca Indica as A Dictionary ofthe ｔ･｣ｨｮｩ｣ｾＯ＠ Terr!'s ｾ･､＠ in
the Sciences of the Musulmans, the Arabic text of which was later repnnted m SIX vol-
umes with continuous pagination by Khayat, Beirut, 1966.
nation of the scope of the science of astronomy. Astrology Ｈ｡ｾｫ｡ｭ＠ al-
nujiim)50
is still kept with the physical sciences, while astronomy ('ilm
al-hay'a) is returned to the mathematical sciences proper51
. In fact he
states that astronomy is one of the principles ＨｵｾｩｩｬＩ＠ of the mathematical
sciences52
•
He tells us that his distinction between astronomy and astrology is
borrowed from the work of the 16th century astronomer 'Abd al-'All al-
Birjandl (d. 1526), who produced an extensive account of that distinction
in the context of his commentary on Jaghmful's introductory text on
astronomy.
The science of astronomy is from among the principles of the mathematical
[sciences]. It is a science in which one investigates the conditions of the
simple superior and inferior bodies in regard to their quantity and quality as
well as their positions and the motions pertaining to them and the conse-
quences issuing from them.
The quantity is either separate like the number of the spheres and some
of the stars, without mentioning the numbers of the elements, for those are
taken from the physical sciences, or continuous such as the magnitudes of
the bodies, the distances, and the day and that which is composed of them.
The quality is such as the form (shakf) from which one finds the circu-
larity of those bodies, and the color of the stars and their light.
The position is such as the proximity of the stars from a specific circle
and their distance from it, as well as the erect-standing of a circle or its in-
clination with respect to the zenith of the inhabitants of specific clime, the
interposition of the earth between the two luminaries and the moon
between the sun and our vision, and such things.
As for the motion, that part of it which is investigated in this science, is
its magnitude and direction, while the investigation of the origin of the
motion and its affirmation with respect to the spheres is in the physical
[sciences]. That which is intended with the necessary and continuous [mo-
tion], according to their opinion, and which is the motion of the spheres
and the stars, to the exception of the motion of the elements such as the
winds, the waves, and the earthquakes, their investigation is in the physical
[sciences]. As for the motion of the earth from west to east, as well as the
motion of the air as it accompanies it and the fire as it accompanies the [ce-
lestial] sphere, that has not been confirmed (yuthbat), and if it were con-
firmed then it would not be strange that its investigation with respect to
magnitude and direction be considered as part of astronomy. That which is
taken to be necessary of motion is retrograde, forward motion, stationary,
equations, as well as other conditions. The author of al-tadhkira did not
mention this condition (qayd), i.e. the condition of the necessary motion,
50 Ibid., p. 44.
51 Ibid., p. 42.
52
Ibid., p. 41, 47.

146 G. SALIDA
for it is apparently unwarranted. The purpose of including the conditional-
ity (}Jaythiya) is to avoid confusion with the science of!he Heaven. ｡ｾ､＠ the
World (al-sama' wa-1-'a/am) for its subject is also the srmples, but Ｑｾ＠ｾｴｯｮ･＠
investigates not the conditionality just ｭ･ｮｴｩｯｮ･ｾ＠ •. rather ｛ｴｨｾ＠｣ｯｮ､ｴｴｩｏｾ｡ｬﾭ
ity] with respect to (min }Jayth) their.ｮ｡ｴｵｲｾｳＬ＠ positiOns, t?e wtsdom ｢･ｨｭｾ＠
their arrangement and order, and theu motiOns but not w1th respect to theu
magnitude and direction. . . .
In summary, the subject matter of astronomy IS the stmple body_ w1th re-
gard to the possibility of the occurrence of the forms ｡ｮｾ＠ the_ motiOns per-
taining to it, while that of The Heaven and World, which IS part ｾｦＮ＠ｴｾ･＠
physical [sciences] is also the simple body but in regard Ｌｾｯ＠ｴｨｾ＠ｾｳｳＡ＿Ｑｨｴｹ＠
of the occurrence of change and permanence. The term possibility was
added in order to indicate that that which is part of the subject matter is the
possibility of occurrence not the occurrence .itself which is assumed
(ma}Jmul), because that which is part of the subject should be accepted ｾｳ＠
occurring which is the possibility of occurrence not the occurrence m
actuality. . . . . .
It is said that the subject matter of either science IS the Simple ｾｯ､ｹ＠ with
regard to the possibility of the occurrence of the ｦｯｾｾﾷ＠ the motiOns, and
the distinctions among them (al-tamayuz baynahuma) IS due to the ｰｲｯｾｦ＠
(burhtin); if the required is proven with the descriptive (inni) proof t?en ｾｴ＠
would belong to astronomy, while if it is proven by the ｣｡ｵｳｾ＠ｾｬｺｭＧＡＧｴＩ＠
proof, it would belong to The Heaven and the World.. The _dtstmctiOn
among the sciences which could be with respect to theu subject matter
could also be with respect to their assumptions (ma}Jmulat). And to say that
the distinction among the sciences is with respect to their subject matter,
that has not been proven with evidence (lam yuthbat bi-1-dalil), it is rather
an accommodating acceptance (ri'aya munasiba).
You should know that the one who investigates the motions of the plan-
ets and their accurate counting (tf.ab{ihti), and constructs proofs for their
positions, can limit himself to the circles only. That is ｣ｯｮｾｩ､･ｲ･､＠ math-
ematical astronomy [Literally non-corporeal, hay'a ghayr muJassama]._ｂｾｴ＠
the one who wishes to conceptualize descriptively Ｈｴ｡ｾ｡ｷｷｵｲＩ＠ the prmct-
ples of those motions in such a manner which is in ｡ｾｲ･･ｭ･ｮｴ＠ with ｴｾ･＠
principles of philosophy (}Jilana) he should conceptuahze the spheres.m
such a manner that the motions of the centers of the planets and the like
will appear at their cinctures (manti{iqiha). That.is considered ｰｨｹｳｩｾ｡ｬ＠ as-
tronomy (hay'a mujassama). To call the phystcal [astronomy] w1th the
name of the science is figurative (majaz). For that reason the author of the
tadhkira said that it was not a complete science, because science is the con-
viction in the issues through proof, and if proof is not mentioned t?en it
would be an account of the problems which are confirmed by proofs m an-
other place. All of this is the summary of what was stated by 'Abd al-AII
al-Birjandi in the commentary on Sharif al-Mulakhkhaf3•
53 Ibid., p. 47-48 of the Khayat reprint.
Tahanawi goes on to say:
That which is mentioned in the science of astronomy is not based on physi-
cal and metaphysical introductions that are usually mentioned by authors in
the introductions of their books. Rather it is by way of going along with the
philosophers, which is not obligatory, for it is possible to prove it without
regard to the introductions upon which it is based.
That which is mentioned in it [i.e. the science of astronomy] some of it
is geometric introd.uctions that can not be doubted such as the observation
of the lunar phases which produce the certainty (yaqin) that the lunar light
is derived from the sun.
Others are introductions judged by reason to be more appropriate and
more fitting, as when they say that the convexity (mu}Jaddab) of the defer-
ent touches the convexity (mu}Jaddab) of the parecliptic at one common
point, and so does its concavity touch the [parecliptic] concavity. They have
no basis for that except that it is more appropriate that in matters celestial
there be no unnecessary separation. So is the case regarding the number of
the spheres that it is nine.
Others are introductions that are mentioned by way of irresolution
(taraddud) without certainty (jazm), as in the case of the variation in the
speed of the sun being either based on the principle of the eccentric or the
epicycle, without certainty in regard to either one of the two.
It is then obvious that the statement regarding the proofs of the problems
of this science as being based on invalid principles taken from the philoso-
phers such as the negation of the existence of the able and the willing (al-
qadir al-mukhtar), the inadmissibility of rupture and re-joining (al-kharq
wa-1-ilti'am) with respect to the spheres, and such things, amounts to noth-
ing, and is based on the ignorance of the problems of this sciences and its
evidence. That is because the observation of the lunar phases necessitates
the certainty that the lunar light is derived from that of the sun, and that the
eclipse is due to the interposition of the earth between the two luminaries,
while the solar eclipse is due to the interposition of the moon between the
sun and the vision, in addition to the confirmation (thubat) of the able and
the willing and the negation of the said principles. For the confirmation of
the able and the willing and the negation of those principles do not negate
the condition being as it was said. All that can be said is that it is possible
under different assumptions, as in the case when we assume the confirma-
tion of the able and the willing that it is possible that the able could blacken
the face of the moon by his own volition, and could light it in accordance
with the observed lunar phases. It is also possible, if we assume a variation
in the motion and conditions of the celestial bodies, that one half of either
one of the two luminaries be bright while the other half be dark, and that
the two luminaries would move around their own centers so that the two
dark faces could be facing us during the solar and lunar eclipses, either
totally if the eclipses are total or partially if they are incomplete.
In this manner is the condition of the lunar phases. But we affirm, de-
spite the existence of the said assumptions, that the condition is as it was

148 G. SAUBA
said by way of the lunar light being derived from that of the sun, and that
the eclipses are due to the interposition.
Such assumptions can also be found in the ordinary (al- 'u/Um al-'adiya)
as well as the experimental sciences (al- 'ulilm al-tajribiya), and even in all
the necessary sciences (fj.aril.riya) despite the fact that the able and the will-
ing is capable of making it so by his own volition. But if we assume that
the introductory principle (al-mabda') is obligatory (mil.jib) then it is possi-
ble that a strange celestial condition could take place, and that would
require that the same strange condition take place according to those
who confess that the events are based on the celestial conditions, and other
such things that are mentioned among the likes of those who deny the
necessities.
If one were to assume that the proofs of the problems of this science are
based on such invalid principles then that would take place only when the
people of this science claim that those [proofs] could not be in any way
other than the one mentioned. But if they were to say that it is possible to
be according to their view, and that it could also be according to another
view then hesitation (tawaqquf) would be inconceivable at that time.
It is enough virtue for them that they imagined, from among the various
possibilities, that which renders with precision the conditions of those plan-
ets, despite their great variations, in such a manner that they could easily
determine the positions of those planets and their aspects with respect to
one another at any time they please, and in such a fashion that it agrees
with the observed so well that it makes the intellects and the minds wonder,
as it was mentioned in ShariJ. al-Tajritf4, and as it can similarly be found in
the Shari) al-Mawaqif5 under the chapter al-jawahir towards the end of the
demonstration of the determination of sides56•
This long quotation from Tahanliwi does not only give the theoretical
framework in which astronomy was considered, but it also supplies us
with the debates that were obviously going on regarding the philosophy
of that science. Similar positions were held by the author of the original
text of the Mawiiqif, i.e. 'Abd al-RaQmlin al-lji (d. 1355)57• The interest-
ing part of this debate lies in the fact that astronomy was correctly ideo-
54 There were two famous commentaries on ｎ｡ｾｉｲ＠ al-Oin Tiisi's (d. 1274) tajrfd al-
'aqti'id: One composed by ｉｾｦ｡ｨｩｩｮｩ＠ (1348), called the old commentary, and the one prob-
ably intended here, which was composed by the fifteenth-century astronomer 'Ala' al-Oin
al-Qushji (d. 1474), called the new commentary. A lithograph copy of the second was ap-
parently printed in Teheran in 1285 (= 1907?). Cf. C. Brockelmann, Geschichte der
arabischen Literatur, Bd. I, p. 509.
55 This is probably the commentary by al-Sharff al-Jumiini (d. 1413), which was appar-
ently printed in Istanbul in 1239. Cf. C. Brockelmann, op. cit., Bd. II, p. 209. Another
commentary was composed by the astronomer ｆ｡ｾ｡ｬｬ｡ｨ＠ al-Shirviini (d. 1496). Cf.
C. Brockelmann, op.cit., Bd. II., p. 209.
56 Kashshtif, Khayat reprint, p. 48-49.
57 Al-Mawtiqiffi 'llm al-Kaltim, 'AI.am al-Kutub, Beirut, n.d., p. 200f.
tified as not being of the same nature as the other mathematical sciences,
say like geometry, where the axioms are self evident and the results de-
rived from them are necessarily true. According to lji, and to his com-
mentators, astronomical principles were not self evident. In fact, they
were philosophical statements. Once accepted, the results derived from
them could be argued in a mathematical fashion. In that regard the final
results were only as good as the assumptions on which they were
based58
•
Of course it did not help that the astronomers themselves were, on
their own, reaching indeterminable results, as in the case of explaining
the variation in the motion of the sun by either assuming an eccentric
principle or an epicyclic one. As we shall see below, a whole genre of
activities in Islamic astronomy which centered around the alternatives
for the Ptolemaic models could be seen, as it was indeed done, as con-
firming the suspicious status of astronomy as a mathematical discipline.
In a word, those astronomers were only giving a possible account of the
disposition of the planets, but no one was under any obligation to believe
that it was the true and necessary disposition.
ASTROLOGY/ASTRONOMY OUTSIDE THE TECHNICAL CIRCLES
What we have seen so far is a set of conceptual schemes that charac-
terized the nature of the two disciplines. By now, I think I have estab-
lished that the two disciplines that went under the same name in the
Greek tradition and in the early Arabic tradition, witnessed a long devel-
opment during Islamic times and were clearly distinguished in both their
subject matter as well as their methods of proof, so that they ended up
being considered under two completely different divisions: The division
of the physical sciences, in the case of astrology, and the division of the
mathematical sciences in the case of astronomy.
58
One should note at this point that such discussions seem to have been raised by pro-
fessional astronomers who were engaged in writing commentaries on such Kaltim works
as tajrid al- 'Aqti'id of Tiisi, and the mawtiqif of Iji. This can be understood if these as-
tronomers themselves were at the same time contributing to the Kaltim literature by virtue
of their engagement with the school system which allowed their hay'a works as well as
their commentaries on Kaltim works to be studied within the normal curriculum of the
school. In order to fully appreciate the true relationship between Kaliim literature and as-
tronomy as it was known from the hay'a work, more work needs to be done on the place
of hay'a works within the school system itself.

150 G. SALIBA
What I would like to do now is to tum to a group of theologian-
philosophers (mutakallimun) who also took part in this debate. My
purpose is to give some assessment of the scope with which the distinc-
tion drawn between astronomy and astrology impacted the society at
large. The sources which I will consider cover a wide range of religious
perspectives, the I:Ianafites, the Ash'arites, the I:Ianbalites, as well as the
Zahirites and if we consider al-Iji, just mentioned, they may include a
Shafi'ite ' as well, although Iji's Shafii credentials are sometimes
doubted.
General Remarks
I do not need to belabor the point that religious scholars in general did
not condone the activities of the astrologer. Only Abu I:Iamid al-Ghazza.II
(1111) was of the opinion that astrology is somehow possible, but only
as much as medicine was possible, i.e. it belonged to that uncertain part
of the physical sciences and was in essence a guess work59• In the same
context, al-Ghazza.II warns the believers against attacking astronomy, for
if they do so in the name of Islam and the predictions of the astronomers
regarding eclipses come to pass, then that would cast doubt on the valid-
ity of Islam itself.
Other authors have produced scores of attacks directed against astrol-
ogy, but none that I know of were leveled against astronomy. This can
only indicate that the religious scholars understood the distinction be-
tween the two disciplines, and singled astrology out for attack. In a dif-
ferent place I have argued that astrology was perceived as the Achilles
heel of Greek philosophy, and that the religious scholars of medieval
Islam used the faults of astrology to cast doubt on the doctrines of Greek
philosophy altogether60.
59 See Il;yii' 'Ulum al-Din, al-Maktaba al-Tijiirlya, Cairo, vol. 1, p. 29, where he says
regarding the reasons why a certain science would be blarnew?rthy: "Secondly, ｴｨｾｴ＠ the
science would be harmful to its seeker in general such as the science of the stars. In Itself
this science is not blameworthy, for it is divided into two parts, a computational (l}isiibl)
one and in that regard the Qur'an has stated that the motion of the sun and the moon is
｣ｯｾｰｵｴ･､＠ for the Exalted and the Mighty has said 'the sun and the moon are computed'
and He said may he be exalted 'As for the moon we have appointe? mansions till she re-
turns like an old shriveled palm-leaf' [Ya Sin, 39], the second IS that of the decrees
(al}kam) which in short amounts to deductions regarding the events based .on causes, and
it is similar to the deductions of the physician regarding the future of the disease from the
pulse. It is also the. knowledge of Go?'s custom and habit .(sunnat ｡ｬｬ｡ｨｾｾＭ 'iidatihi) with
respect to his creation. But the canomcallaw (sharj has disapproved of It . He goes on to
say that "astrology is pure guessing".
60 See "The Development of Astronomy in Medieval Islamic Times", Arabic Studies
Quarterly, 4 (1982), p. 211-225, now reprinted in G. Saliba, A History of Arabic
I also do not need to repeat here the reasons for which astrology was
attacked, for a good number of the arguments against it were already
known in Antiquity, and were ably summed up in the monumental work
of August Bouche Leclercq, in his Astrologie grecqutf>1• What I will do,
however, is to simply list the more important arguments, without any
elaboration, in order that I could designate later the originality and the
direction of the religious arguments against astrology.
I will not repeat the relatively trivial objection involving the problem of
free will and predestination. Other arguments62 included the famous prob-
lem of the twins, i.e. born at the same time and having different destinies;
the problem of groups dying in the same battle despite their different
horoscopes; one does not know all the stars, how could one determine
their effects; the natures of the stars are imperfectly known and so are
their influences; the human mind cannot comprehend the multiplicity of
factors governing a horoscope, how could one tell the implications with
any certainty; precise measurement of the positions of the stars is virtu-
ally impossible, how could one read their influence if we cannot tell their
position with any precision; even if one accepted the principle of astrol-
ogy, the various astrological systems tell different implications, which one
is true? to be anywhere precise astrology should consider the moment of
conception as the true moment for the horoscope and not the moment of
birth, the first is virtually impossible to know; the celestial spheres are of
one pure nature, how could different parts of them have different natures
and different influences; astrologers are often in disagreement regarding
their own prognostications, how could they be trusted? and finally, since
astrology claims to be an "experimental science" and the celestial posi-
tions take thousands of years to repeat themselves, if they ever do, how
could one build experience on this scanty evidence?
Except for the last argument, all the others really touch upon the ques-
tion of the difficulty of the practice of the science. As such they could be
summarily answered by someone who claims to have perfected the
methods in order to better read the designations of the stars.
Astronomy: Planetary Theories During the Golden Age ofIslam, NYU Press, NY, 1994,
p. 51-65.
61
Ernest Leroux, Paris, 1899, passim but especially p. 570ff.
62 These arguments were extensively used by Ibn Qayyirn al-Jawziya (1350), and were
summarized by John Livingston, "Ibn Qayyirn al-Jawziyyah: A Fourteenth Century
Defense Against Astrological Divination and Alchemical Transmutation", JAOS, 91
(1970), p. 96-103. Most of them were already used by Cicero (1st cent. B.C.) in De
divinatione, Loeb, 1979.

152 G. SALffiA
The last argument is somewhat significant and we should stop to ex-
amine it more closely. We may recall that it was the same argument used
by Farabi in his own refutation of astrology mentioned above. The argu-
ment was also repeated by the zabirite Ibn I:Iazm (1046), as we shall see
below, as well as by others. In essence the argument is against the theo-
retical foundation of astrology and not against its difficulty of practice.
What this argument says is that we cannot use experience to accumulate
knowledge about the influence of the stars, simply because each instan-
taneous celestial configuration is in a sense unique and could not repeat
to allow this accumulation. In modern statistical terminology, we do not
have enough cases to form a significant judgment.
In what follows, I will try to isolate those arguments which were pro-
duced by the religious scholar that are similar in nature, in that they
touch on the core of the science of astrology. But most importantly, I
will also point out the distinction that these scholars make with respect
to astronomy whenever they do.
Al-Miituridi, Mul}ammad b. Mul}ammadAbu ｍ｡ｮｾｵｲ＠ (944)
This relatively early I:Ianafite theologian has left us a coherent kaliim
text under the title Kitiib ｡ｬＭｴ｡ｷｾｩ､ＶＳ
＠ In it he argues against all non-
Muslim and heretic claims which have a bearing on the Islamic religious
dogma. Chief among those issues is the issue of the eternity or created-
ness of the world. In a chapter devoted to the doctrines of the eternalists
(dahriya)64
, he singled out two groups: those who believed in the "na-
tures" Ｈ｡ｾｾ｢＠ al-tabii'i), and the astrologers (munajjima)65• He claims
that they both believe that the original matter of the world was never cre-
ated, and was always there, and they only differ as to the time of its fash-
ioning into what was later on called the world, i.e. when it was impreg-
nated, so to speak, with the form that gave it the present shape.
The doctrine of natures, according to Maturidi, implies that the world
was formed from the elements by the mere action of the natures of those
elements on one another, hence did not need the intervention of God.
Since it does not concern us here, I will not go into his interesting refuta-
tion of this doctrine. Instead I will turn to the second doctrine, which
63
Edited by Fathallah Kholeif, 2nd. ed., Recherches: Ser. I, Pensee Arabe et
Musulmane, Tome L, Dar El-Machreq, Beirut, 1982.
64 Ibid., p. 141.
65 Ibid., p. 143.
was that of the astrologers. It implied that the world came into being as a
result of the actions of the stars, and that the same stars continue to gov-
ern this world by their motions with respect to one another. To those,
Maturidi says that the motions of the stars themselves could not be infi-
nite, for he had already shown that every motion, and here he means that
in an Aristotelian sense, must have a mover and thus at some point those
motions were initiated in time. The movers themselves could not be the
elements, for they are by definition contradictory elements, and the con-
tradictory always leads to annihilation. Therefore one could not say that
the contradictories existed in an infinite time for then they would annihi-
late each other. Throughout his argument, whether against the doctrine
of natures or that of the astrologers, Maturidi always relies on the impos-
sibility of the infinite succession.
But he finally asks the epistemological question66, namely how do we
know that the world is administered by the stars. If it is by transmission
of authority (sam}, then religious authority is more appropriate to be-
lieve and it does not say so. If it is by observation, he says one does not
witness the action of the planets, and thus cannot have observational data
to judge. If it is by induction, then one could not be sure that the ob-
served facts on the earth are not themselves influencing the positions of
the planets, and not the reverse.
As far as I can tell, Maturidi, does not single out the astronomers as a
different group, but from what we know of the holders of the doctrines
that he attacks, we can be certain that he meant the astrologers alone in
his attack.
Al-Biiqilliinl, AbU Bakr Mul}ammad b. al-Tayyib (1013)
This second generation Ash'arite, who was apparently much admired
by the later I:Ianbalite theologian Ibn Taymiya (1328), has left us a text,
Kitiib ｡ｬＭｔ｡ｭｨｬｾＷ
Ｌ＠ in which he also attacked the astrologers. Just as was
done by al-Maturidi, al-Baqillani also perceived the astrologers as a
group similar to those who held the doctrine of the natures. It is not co-
incidental that the fourth chapter of his book is devoted to the attack
against the doctrines of the natures, and the one immediately following,
the fifth is devoted to the attack against the astrologers. Both of these
66
Ibid., p. 145.
67
Edited by Joseph McCarthy, Publications of Jarni'at al-l:likma (Baghdad), al-
Maktaba al-Sharqiya, Beirut, 1957.

154 G. SALIDA
attacks follow his chapter in which he had already proven the created-
ness of the world.
This is the context in which these arguments were formulated. As I
have done in the case of al-Maturidi, I will dispense with his arguments
against the doctrine of natures for its lack of relevance to our topic. But I
would like to point out that in the concluding argument of his attack
against the doctrine of natures, he also raises the epistemological ques-
tion against those who believed in the main Aristotelian tenet regarding
the distinction drawn between the earthly and the celestial motions. He
then says: "Who informed you that it is impossible for the celestial
sphere to stop one day, or that it is impossible for it to move in one of the
six linear directions, despite the fact that you had not seen that be-
fore?"68 The question is interesting in that it raises the issue of the epis-
temological foundation of any science.
As for the astrologers (munajjimun) he attacks them on the issue of
the responsibility of the planets and the spheres for the actions in this
world. Here he says that those planets and spheres are themselves cre-
ated and could not be responsible for further creation. The argument
hinges on their multiplicity, for if they were capable and alive in order to
create, then they would fall into disagreement among themselves, just
like all living things. On the epistemological ground again, we have no
necessary knowledge that they are capable or alive.
Baqillani then goes through some of the standard arguments against
the astrologers mentioned above, and concludes by raising an interesting
question. He says that there are those Muslims who say that the planets
are only signs (daliiliit) created by God just for that purpose. To those,
he says: Since there is no necessary relationship between the signs and
the events, then they do not indicate anything. For signs to have any sig-
nificance they must be clearly related to the acts, as in the case of writ-
ing which indicates the existence of a writer. But it is not the same with
the planets.
Here again, there is no specific mention of the astronomers, and thus
our reading of Baqillani is limited to his attack on the astrologers, and
the kinds of issues that he raises against their discipline.
Ghazziili, AbU /fiimid (1111)
I have already referred to the ambivalent position held by this
Ash'arite, in his lf;yii' 'Ulum al-Din, where he says that astrology is like
68 Ibid., p. 45.
medicine, possible, but not religiously recommended. We also noted his
admonition to the believers regarding the validity of astronomy. I only
mention him again in order to indicate that the conceptual problem re-
garding the theoretical foundation of a science was not simple, and could
not be summarily dismissed as an Ash'arite, or a l:lanbalite position, for
we can clearly see that there were many shades of thought within each
doctrinal position.
Moreover, in his .al-Munqidh min al-tf.aliif>9
, Ghazzili gives a brief
description of the sciences, and under philosophy he says of the mathe-
matical sciences the following:
As for the mathematical sciences, they involve the sciences of arithmetic,
geometry and astronomy ('ilm hay'at al-'a/am), and none of them has any-
thing to do with the religious sciences, either to support or to deny them.
Rather they are demonstrative matters (umur burhtiniya) that could not be
denied once they were known and understood. However, they generate two
mishaps (afa) [...]1°.
The first concerns the danger that one may admire all the philosophi-
cal sciences on account of the demonstrative powers of the mathematical
sciences. Thus one may think that the metaphysics of the ancients which
was always guess work was as solid as the demonstrative science of
geometry, for example.
The second mishap is the one with greater importance for our
purposes. He says regarding it:
This second is due to an ignorant friend of Islam, who thinks that religion
should be supported by the denial of all the sciences attributed to them [i.e.
the mathematical sciences]. He would then deny all of their sciences and
would claim their ignorance so much so that he would even deny their
statements regarding solar and lunar eclipses. He would claim that their
statements are contrary to religious law. When such statements reach those
who know these matters with indelible proof, they would not doubt their
own proof, rather they would believe that Islam is based on ignorance and
the denial of indelible proofs. Their love for philosophy and their hatred for
Islam would then increase. Anyone who claims that Islam can be supported
by denying these sciences commits a greater crime towards religion. There
is nothing in religious law that confirms or denies these sciences, nor is
there anything in these sciences that confirms or denies religious matters.
And when may peace and prayers be upon him says: "The sun and the
moon are two of god's signs, they are not eclipsed for the death of anyone
nor for his life, and when you see them rush to mention god and to pray",
69 Edited and translated by Farid Jabr, 2nd. ed., al-Lajna ai-Lubnanlya Ii-Tarjamat ai-
Rawa'i', Distributed by ai-Maktaba al-Sharqlya, Beirut, 1969.

156 G. SALIBA
that does not mean that one should deny the science of arithmetic which
leads to the knowledge of the motions of the sun and the moon, their con-
junction and their opposition in particular71
•
This position of Ghazzall is not only important for its insistence on
including astronomy, not astrology, among the mathematical sciences,
but in its defense of astronomy against the ignorant, and its insistence
that the mathematical sciences were indeed neutral vis-a-vis religion. We
should also note that Ghazzii.li does not include music among the math-
ematical sciences that he enumerates.
Amidi, Sayf al-Din (1233)
The last Ash'arite I wish to consider here has left us at least two works
on kaliim: one is apparently very voluminous unedited work known as
Abkiir al-Afkiir, and the other is an abridgment of the first called Ghiiyat
al-Muriim fi 'ilm al-Kaliim72• I only have had access to the second work.
In this work Amidl attacks the astrologers as well. But his argument is
slightly different from the earlier Ash'arites. In fact he says that his ear-
lier friends Ｈ｡ｾｽｊｩｩ｢ｵｮｩｩＩ＠ were soft on the subject, and their attacks were
more like child play73• In the context of discussing the actions of the
Necessary of Existence (wiijib al-wujud) he approaches the argument
under three main sections. The first section, which he calls rule (qii'ida),
asserts that there is no creator besides God74
• He says that this rule was
held by the Muslims, and the only ones who differed with them in its
regard are some of the metaphysicists (iliihiyyin), some of the duelists
and the mu'tazilites, and the astrologers. I will only discuss his attack
against the astrologers.
In the presentation of the opinions of the astrologers, he characterizes
them as "those who hold that the stars and the planets are the creators
and that there is no creator other than them"75
. These are obviously ex-
tremist non-Aristotelian astrologers. His response to them76
is to assert
that those planets and spheres are either of necessary existence, or are
only possible, or some are necessary and some are possible. If they are
71
Ibid., p. 21-22.
72
Edited by I:Iasan ｍｾｵ､＠ 'Abd al-La!if, al-Majlis al-A'Ia li-1-Shu'iin ai-Isllimiya,
Cairo, 1971.
73
Ibid., p. 210.
74
Ibid., p. 203.
75
Ibid., p. 206.
76 Begins, on p. 210.
necessary then their mere multiplicity would argue against them, for the
metaphysicists have already demonstrated that you could not have more
than one necessary existence. Moreover, if one were to assume the non-
existence of the necessary existence then a contradiction would ensue in
regard to it. But it is obvious that if a reasonable man were to assume the
non-existence of the planets and the spheres, that assumption by itself
would not produce a contradiction in his mind. In the same way, such a
contradiction wouid not arise if one were to assume the existence of an-
other planet or another sphere. How could anything that is in this fashion
be of necessary existence in itself?
Moreover, if they were necessary, then all that would share with them
the essence (ma 'nii) of substance would also be necessary. Accordingly
it would be impossible to deny the createdness of the substances of fixed
forms pertaining to the bodies of the elements (imtinii' al-qawl bi-/:tadath
al-jawiihir ｡ｬＭｾｵｷｩｩｲｩｹ｡＠ al-thiibita li-1-ajriim al- Ｇｵｮｾｵｲｩｹ｡＠ ). That would
lead to a contradiction77
•
In this fashion he demonstrates that it is not possible that some of
them be necessary and some possible, rather they should all be possible.
If that were so, then there must be something outside them that would
enhance their possibility and it is not possible that they would not have a
beginning.
He goes on to say that the astrologers have no way of proving that ｴｨｾ＠
planets cause the events in the sublunar region even when they admit
that God has created those planets. It could very well be that God would
set his custom that such events would follow each other.
This text of Amid! does not only bring to mind the doctrine espoused
by Ghazzall in regard to God's custom, but challenges the astrologe_rs in
a manner which, as far as I can tell, has never been done before. It IS no
longer relevant to attack the astrologers on the grounds that their ､ｩｳ｣ｾﾭ
pline is difficult to achieve, because, now their ､ｩｳ｣ｩｾｬｩｮ･＠ｾ｡ｳＮ＠ｾｯ＠｢｡ｾｉｳ＠
even if they could achieve all the precision they so desued. Amidi demes
even the possibility that such planets and spheres could by ｴｨ･ｭｳ･ｬｶｾｳ＠
influence the events in this world, no matter how well we know theu
positions. This is in fact the height of the Ash'arite doctrinal attack
against the astrologers.
Another remark made by Amid! should be highlighted at this point
especially in regard to what we will say later in connection with the
77 Ibid., p. 211.

158 G. SALIBA
ｰｯｾｩｴｩｯｮ＠ of Ibn Taymiya on astronomy. ｾｨ･ｮ＠ denying the necessary
existence for the planets and the spheres, Amidi states that there would
not be a contradiction if we assumed their non-existence, in the same
fashion that there would not be a contradiction when we assume an addi-
tional planet or sphere78
• The assumption of an additional planet or
sphere as a general statement can also be taken to refer to the practice of
the reformers of Ptolemaic astronomy when they assume the existence of
additional epicycles, which are by definition additional spheres. If A.midi
ｾ｡､＠ this in mind then it would demonstrate the extent to which the prac-
tices of the reformers of Ptolemaic astronomy were known outside their
circles. We will have occasion to return to this point when considering
the position of Ibn Taymiya whom we shall take up next.
Ibn Taymlya, AbU al-'Abbtis Taql al-DlnAI;zmad b. 'Abd al-lfallm (1328)
I have not found a special treatise in which this J:Ianbalite theologian
attacks astrology. But in his work titled Dar' Ta'tirud al-'Aql wa-l-
Naqf79, he has occasion to consider the issue of ｡ｳｴｲｯｮｯｾｹ＠ as part of the
mathematical sciences. His approach is especially revealing of the status
of astronomy in his time.
While discussing the priority of prophetic texts over man's rational
deductions he has occasion to refer to the mathematical sciences. His
superficial argument against the supremacy of the rational sciences
stems from the frequent disagreement among those who profess to base
their knowledge necessarily on these sciences. He then lists the relative
sects and their disagreements over the same issues. He says, for exam-
ple, that the mu'tazilites who claim that their denial of God's attributes is
derived from indisputable rational evidence are opposed by those who
affirm God's attributes on the basis of equally indisputable rational
evidence80•
He continues to say that the farther the group is from the traditional-
ists (al-sunna) the greater their differences will be81• Among such groups
he mentions the ｂ｡ｾｲｩ＠ mu'tazilites, the Baghdadis, the followers of
I:Iasan ｡ｬＭｂ｡ｾｲｩＬ＠ and the Shi'ites whose factions amount to seventy-two
sects. When he reaches the groups of the philosophers he says:
78
Ibid.
:Edited by Mui_Jammad Rashiid Salim, Jiimi'at al-lmiim Muhmmad b. Sa'iid, 1979.
Ibid., vol. I, p. 156. ·
81
Ibid., p. 157.
nothing brings them together, and they are at greater variance than all the
sects of the Muslims, Christians and Jews. The philosophy followed by al-
Fiiriibi and Ibn Sinii is the peripatetic philosophy, the followers ofAristotle,
the author of the mathematical sciences Ｈｾｩｩｬ［Ｎｩ｢＠ al-ta'iilim?). The difference
between him and his predecessors takes a long time to describe. And the
difference among his own followers is also long to describe. As for the re-
maining sects, if one were to tell only about their differences in regard to
astronomy ('ilm al-hay'a) it would be more than all the differences of all
the sects of Islam (rawii'if ahl al-qibla). That when astronomy is a math-
ematical computational discipline ('ilm riyikfi IJ.isiibl) and is the most valid
of their sciences (min ｡ｾ｡ｩｊＮ＠ 'uli:tmihim). And if their differences regarding it
are so great, what could one say in regard to their differences in the physi-
cal [sciences] or logic? or even metaphysics?
Consider this in connection with what was reported about them by al-
Ash'ari in his book "Maqiiliit Ghayr al-Isliimiyyln" and by the Judge Abii
Bakr in his book "al-Daqii'iq" in regard to the mathematical and the physi-
cal sciences. Their differences in that regard are many many times more
than those which were mentioned by Shahrastiini and his like who report
their statements. Their differences in regard to the mathematical sciences
which is the most valid of their sciences - could almost be uncountable.
Even the same book regarding which their majority agreed - which is the
book of the Almagest of Ptolemy - contains many problems which cannot
be proven correctly (fi-hi qacj.iiya kathlra Ia yaqilm 'alayhii dalU ｾ｡ｬｽＮｬｬ［ＮＩＬ＠ and
has many problems disputed with him [i.e. Ptolemy] by others, and it con-
tains issues based on reported observations which could be erroneous and
faulty82•
This text does not only dispute the validity of the mathematical sci-
ences in general, rather it raises some interesting questions with respect
to astronomy in particular. The fact that Ibn Taymiya reports that there
are problems in the Almagest which are not proven seems to signal the
kind of criticism addressed against Ptolemy by someone like Jabir Ibn
Aflal). of Spain (c. 1200). But more importantly, his statement regarding
the general disagreements among the astronomers may very well refer to
the variations among the zlj writers. But since he mentions the Almagest
in specific, which is not a zlj text, this seems to indicate that he may be
referring to all the new configurations that were proposed during Islamic
times in order to correct the configurations proposed in the Almagest.
One could imagine that none of the astronomers intended by Ibn
Taymiya would have claimed that his own configuration is the final valid
one, or that it was the only one. Even Ptolemy himself did prove in the
Almagest that the motion of the sun could be described by either one of
82 Ibid., p. 157-158.

160 G. SALffiA
two hypothesis, the eccentric and the epicyclic. And that may have
worked against him. To Ibn Taymiya, this kind of science produces only
possible statements, and is therefore not to be considered as demonstra-
tive like the other sciences whose results are necessarily true. Most as-
tronomers who were involved in the reformation of Ptolemaic astronomy
would agree with Ibn Taymiya on this issue.
On a different level, Ibn Taymiya's statements also demonstrate how
well he knew of the attempts of the astronomers to reform Ptolemaic as-
tronomy. This can only mean that such efforts were known outside the
circles of the astronomers, and their shortcomings were very well
accepted.
Moreover, the great esteem for the students of the Almagest, with
which Ibn Taymiya held them is paralleled by a similar statement by his
younger contemporary, KhalTI b. Aybak ｡ｬＭｾ｡ｦ｡､ｩ＠ (d.l365). In his text on
the biographies of the blind83
, ｾ｡ｦ｡､ｩ＠ had the occasion to refer to the as-
trologers who claimed to predict the blindness of a child as being caused
by celestial phenomena. In his attack against them, he identifies the as-
trologers as "people of experience and inspiration" Ｈ｡ｾｬ［ｵｩ｢＠ al-tajriba wa-
1-ilhiim) a designation unknown from earlier sources, but consonant with
the reference to astrology as an experimental science. The gist of
ｾ｡ｦ｡､ｩＧｳ＠ argument against them is that for their prediction to be true,
they must assume different sections of the heaven to have different na-
tures, a well known general argument from antiquity. But then he goes
on to say that the celestial sphere
has been proven to be of simple nature by the people of the Almagest
Ｈ｡ｾｊＺｵｩ｢＠ al-majisfl). Moreover, the simple has its parts similar to the whole.
And the people of the Almagest are the people of the fundamentals of as-
tronomy Ｈ｡ｾｊＺｵｩ｢＠｡ｬＭｵｾｵｬ＠ fi 'ilm al-falak). And if one were to assume the
heavens to be composite, he would lead himself to several absurdities
(fasadat 'alayhi ｾｵｬｵｮ＠ kathira) that we have no space to mention here84•
ｾ｡ｦ｡､ｩ＠ does not only agree with Ibn Taymiya that the students of the
Almagest are the most reliable, but that" they are clearly distinguishable
from the astrologers. The point I wish to make in this context is that the
two disciplines were by now clearly differentiated, and the level of the
discussion had reached the stage where such critics were questioning the
fundamental validity of the mathematical sciences altogether.
83
Nakt al-Humyiin fi Nukat at- 'Umyiin, al-MaJba'a al-JamaJ.Iya (Cairo), 1900, p. 63-
65.
84
Ibid.
Ibn Qayyim al-Jawz'iya (1350) and Kushyiir Ibn Labbiin (fl. 1000)
I have already referred to this author before, and have used his exten-
sive attack against the astrologers to list the kind of attacks the astrolo-
gers were subjected to. Of the works of this student of Ibn Taymiya, we
have his ｍｩｦｴｩｩｾ＠ Dar al-Sa'iida85
, which included the ｭｯｳｾ＠･ｬ｡ｾｯｲ｡ｴ･＠｡ｾﾭ
tack on astrology that I know of from medieval Islamic tunes . In thts
work, Ibn Qayyim does not only give his own opinion of the astrologers
but collects opinions of others, thus producing an anthology of the at-
tacks against astrology.
One quotation is particularly interesting here, namely the one ｴｾ｡ｴ＠ he
lifts from the introduction of Kushyar's work on astrology. In the mtro-
duction, Kushyar says:
Most of those who devote themselves to the first science [Ibn ｑ｡ｹｹｾ＠ｩｾﾭ
serts] meaning the science of astronomy (ya'ni 'ilm al-hay'a) deny this SCI-
ence and deny its utility, and they say that its results come to pass by sheer
accident, without any proof whatsoever!?.
This does not only mean that Ibn Qayyim himself was well aware of
the distinction between the two disciplines, but that the astrologer/
astronomer Kushyar was also aware of the same distinction as early as
the tenth and eleventh centuries.
Ibn Hazm, Abu ｍｵｾｭｭ｡､＠ 'All b. ａｾｭ｡､＠ b. Said (1064)
This Zahirite theologian offers a similar perspective on the status
of ｡ｳｴｲｯｬｾｧｹ＠ in Islamic medieval times. In his book Mariitib al- ｾｵｬｵｭ＠
(The Hierarchy of the Sciences)88
, he ｾ｡ｳ＠ｾｾｳ＠ to _say about the sctence
of the stars: "The science of the stars ts divtded mto the knowledge of
astronomy ('ilm al-hay'a wa-1-ta'dil) together with its proofs, and
that which they mention by way of decrees (qa(jii')89." Later on he
says:
One should know from the computational [science] (?isab) that which aids
in the knowledge of the qibla, the midday and the times of prayers. That
85 1vo Volumes in one, Dar al-Kutub al-'Ilmiya, Beirut, n. d.
86 Ibid., vol. 2, p. 125f.
87 Ibid., vol. 2, p. 146. . · b th
ss Ibn I:Iazm, Risiilat mariitib al-'ulum, published ｴｯｧｾｴｨｾｲ＠ｷｩｴｾ＠ other treatises Y_ :
same author in Rasii'il Ibn lfazm al-Andalusl, ed. ｾｾｽｳ｡ｮ＠ Abbas, Maktabat al-K.hanJI
(Cairo) and Maktabat al-Muthannli. (Baghdad) n. d.
89 Ibid., p. 79.

162 G. SALIDA
cannot be known with certainty except through the science of astronomy
Cilm al-hay'a), and the truth of the proofs is only known by those who
know religious philosophy (kaliim)90.
It is interesting to note at this point that according to Ibn J:Iazm kaliim
is part of the religious sciences, while metaphysics, and physics fall
under logic.
Later on when he returns to astrology, he says that "it is a collection
of false statements and fictitious utterances that do not come true. Proof
is available regarding the invalidity of these utterances, which we have
detailed in a different place"91•
Indeed he did that in his other heresiographic work, al-fi$al wa-1-milal
wa-l-ni/:laf2, which he must have composed before the mariitib. And in
that book he draws a clear distinction between astrology and astronomy.
Although he treats both sciences in one chapter devoted to the problems
of the stars (qa{iiiya al-nujum), he says of astronomy:
As for the knowledge of their motion through their spheres, their periods
(iinii'), their ascensions, their distances, their altitudes, and the variation in
the centers of their spheres, that is a true noble science Cilm ｾ｡ＯｊＮｩＯｊＮ＠ raft},
through which the student could come to see the greatness and the power of
the almighty, and the certitude of his influence, his creation and his fash-
ioning of the world together with all that is in it. Through it [i.e. astro-
nomy] one is obliged to confess the existence of the creator. One can not do
without it when it comes to the knowledge of the qib/a, the times of
prayers, as well as the knowledge of the crescent visibility in order to deter-
mine fasting and the breaking of the fast, and the knowledge of the two
[types] of eclipses93•
As for astrology (qafjii') any affirmation concerning it is false (ammii al-
qafjii' fa-1-qa( bi-hi kha[a ')94•
He then goes on to enumerate more than eight proofs of its invalidity.
What concerns us here, is that there was a clear distinction between
astronomy and astrology in eleventh-century Andalus as well, and that
astronomy was already seen by religious scholars as a handmaiden of
religion. Nothing is said however about the disagreements among the as-
tronomers as was cited by Ibn Taymiya.
90
Ibid., p. 82.
91
Ibid., p. 88.
92
Khanji Press, Cairo, 1903.
93
Ibid., vol. 5, p. 37.
94
Ibid.
CONCLUSION
Now that we have seen the extent to which the distinction between
astronomy and astrology was carried out in Islamic medieval times, it is
worth repeating that this remarkable clarity did not come all at once. We
have seen that practitioners of the two sciences themselves referred to
their disciplines with the same name, science of the stars. But sometime
during the tenth century the separation of astronomy as a distinct disci-
pline necessitated the reference to it with a new name, hence the birth of
the terminology 'ilm al-hay'a.
I must quickly confess that I do not know of such a designation from
the Greek sources, and thus I have to conclude that this branch of as-
tronomy was created in Islamic times in order to respond to the need of a
separate discipline. But with time, it became specialized enough that it
began to designate the mathematical-physical part of astronomy, i.e. that
part in which one speculated about the mathematical hypothesis that
could describe the physical phenomena of the universe. The need for this
type of mathematical approach to astronomy was apparently religiously
condoned, and I know of no religious scholar who spoke against it. In
order to illustrate this well accepted status of astronomy, I quote the fol-
lowing anecdote from the biography of 'Abd al-Salam Ibn 'Abd al-Qadir
al-Baghdadi (d. after 1193), who was apparently very well versed in the
rational sciences, as it was preserved by the thirteenth-century biogra-
pher al-Qif!f5. During one of the rare public attacks on the rational sci-
ences, Qif!I reports about someone by the name of Ibn al-Maristaniya
(d. 1203) who took it upon himself to prosecute this 'Abd al-Salam in
public. The behavior of Ibn al-Maristaniya was so odd that it was de-
scribed in some detail. Then Qif!I says:
I was told by the wise Yiisuf al-Sabti al-Isra'TII, when he said: "I was in
Baghdad at that time on some commerce, and I attended the gathering and
heard the words of Ibn al-Maristaniya, and saw in his hand the astronomy
book (kitiib a/-hay'a) of Ibn al-Haytham". He was pointing to the circle
which he used to illustrate the celestial orb and saying: "this is the incred-
ible calamity, the deafening disaster, and the blind catastrophe". When he
finished his speech he tore it apart and cast it into the fire. I then realized
his ignorance and his prejudice, for there was no unbelief in astronomy
(lam yakun fi-l-hay'a kufr). On the contrary it is the path to belief, and the
knowledge of the might of God, may He be exalted and mighty, and the
knowledge of His excellent management of His creation96
•
95 Ta 'rikh al-lfukamii', p. 228-229.
96 Ibid., p. 229.

164 G. SALffiA
This anecdote does not only,isolate this strange instance, but makes it
very clear that, according to this merchant at least, the religious status of
astronomy was beyond any doubt.
Having said that, we should be reminded that the theoretical philo-
sophical status, as it was perceived by Ibn Taymiya, was not yet settled,
and its relationship to the mathematical sciences was not all that
confirmed.
PROPHECY AND REVElATION IN ALFARABI'S
POLITICAL PHIWSOPHY
Muhsin MAHDI'
The followers of the revealed religions are for the most part pious be-
lievers for whom religion consists of doctrines they hold to and try to
understand as best they can, and practices they perform to the best of
their ability. Those who aspire to be theologians and philosophers find
two main approaches in the traditions they study. First, a tradition that
sees prophecy and revelation as contact between the highest form of hu-
man intelligence and a higher intelligence above and beyond it. This is
the view of the major Muslim philosophers up to and including
Averroes. The second sees prophecy and revelation as contact between a
human being and something beyond all intelligence and transcending all
intelligibility. This is the view of those who followed the Neoplatonic
tradition, and it included not only philosophers but theologians and mys-
tics as well. The difference between the two views corresponds to the
technical distinction made by scholastic theologians between the natural
and the supernaturaP.
The second approach was known to Alfarabi through the works of
Plotinian Neoplatonists and Christian and Muslim theologians; and he
reports some of their arguments2
• Prophecy and revelation, so the argu-
ment went, are beyond human comprehension: they are supra-rational.
On the basis of the miracles he performed or the testimonies of those
who saw him, one must admit that the person who brought us the revela-
* The first draft of this paper was prepared for delivery on 15 December 1987 in the
Nimphenburg Palace in Munich as the 25th Werner Heisenberg Lecture sponsored by
Bayerische Acadernie der Wissenschaften and the von Siemens Stiftung.
1
This is a distinction that corresponds to Maimonides' (Guide U 32) second and first
"opinions concerning prophecy" [Arabic text (Daliilat ｡ｬＭｾＧｩｲｩｮＩ＠ edited by S. Munk; Le
Guide des egares, 5 vols., Paris, 1856-1866; English translation by Shlomo Pines, The
Guide of the Perplexed, Translated with an introduction and notes, with an introductory
essay by Leo Strauss, Chicago, 1963; partial translation by Ralph Lerner and Muhsin
Mahdi, in Medieval Political Philosophy: A Sourcebook Sec. 12).
2 Enumeration ofthe Sciences, p. lOSt!. [Arabic text edited by Osman Amine, ｬｾｍｩｩＧ＠ al-
'ulum, 2nd ed. Cairo, 1949; English translation of chapter 5 by Fauzi M. Najjar, The Enu-
meration of the Sciences, in Medieval Political Philosophy: A Sourcebook. Edited by
Ralph Lerner and Muhsin Mahdi with the collaboration of Ernest L. Fortin, New York,
1963, repr. Cornell Paperbacks, Ithaca, NY, 1984, Sec. 1).

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