Thursday, March 23, 2023

2023: Ibn al-'Adim - Ibn al-Haytham

 


Ibn al-‘Adim
Ibn al-‘Adim (Kamal al-Din ibn al-Adim) (1192-1262).  Historian of Aleppo.  He wrote a biographical dictionary of men connected with Aleppo, and a history of the city.

Kamal al-Din Ibn al-Adim was a historian from Aleppo. He is best known for his work Bughyat al-Talab (The Student's Desire), a collection of biographies of famous men from Aleppo. Other well-known books by Ibn al-Adim are his history of Aleppo: Zubdat al-Halab fi ta'arikh Halab (The cream of the history of Aleppo) and his guide for the making of perfumes Kitab al-wuslat (or wasilat) ila-l- habib fi wasf al-tayibat wal-tibb.

Kamal al-Din ibn al-'Adim see Ibn al-‘Adim


Ibn al-‘Amid, Abu‘l-Fadl
Ibn al-‘Amid, Abu‘l-Fadl (Abu‘l-Fadl ibn al-‘Amid) (d. 970).  Vizier of the early Buyids and man of letters of Qum.  His reputation was due to his prodigious memory, to his generosity and to his friendly character.  He is praised for his correspondence.
Abu'l-Fadl ibn al-'Amid see Ibn al-‘Amid, Abu‘l-Fadl


Ibn al-‘Arabi, Muhammad ibn Ziyad
Ibn al-‘Arabi, Muhammad ibn Ziyad (Muhammad ibn Ziyad ibn al-‘Arabi) (767-846).  Philologian of the school of Kufa.  About twenty works are attributed to him.
Muhammad ibn Ziyad ibn al-'Arabi see Ibn al-‘Arabi, Muhammad ibn Ziyad

Ibn al-‘Arabi, Muhyi‘l-Din al-Ta‘i
Ibn al-‘Arabi, Muhyi‘l-Din al-Ta‘i (Muhyi‘l-Din al-Ta‘i ibn al-‘Arabi) (Muhyi‘d-din ibn ‘Arabi) (al-Shaykh al-Akbar) (July 28, 1165 - November 10, 1240). Andalusian Arab Sufi mystic and philosopher. His full name was Abū 'Abdullāh Muḥammad ibn 'Alī ibn Muḥammad ibn al-`Arabī al-Hāṭimī al-Ṭā'ī.  He is considered to be one of the greatest, and certainly the most prolific, Sufis of Islam.  Born in Murcia, Andalusia (Spain), he impressed his father’s friend Ibn Rushd (Averroes), who was then a judge in Seville. 

He travelled far and wide in the Muslim countries. He traveled throughout the centers of learning of his time: Seville, Cordoba, Marrakech, Tunis, Cairo, Konya, Mecca, Baghdad, and Damascus, where he died and where his tomb has become a popular shrine.

In 1230, Ibn ‘Arabi settled in Damascus where he died and was buried.  There seems little doubt that he is the author of some 400 works, among which are a full exposition of the author’s Sufi doctrine, and a summary of the teaching of 28 prophets from Adam to the Prophet.  His ideas had their most profound influence in Anatolia.  It has been suggested that his description of his “ascension to heaven” (in Arabic, mi‘raj) from the world of being to the station in God’s presence influenced Dante.

Although Ibn ‘Arabi founded no order -- no tariqa --, he nevertheless influenced speculative Sufi thought more profoundly than any other thinker.  Ibn ‘Arabi left a list of his own literary output.  This list totaled 270 works, 176 of which dealt with Sufism.  Two of the 176 works have received special attention.  The first, The Meccan Revelations, garnered attention because it is partially autobiographical and otherwise sets forth much of interest about famous Sufis as well as the central teachings of Sufism.  The second, The Wisdom of the Prophets (Fusus al-Hikam), in which each of the 27 major prophets is allotted an individual chapter that describes not the prophet but rather the approach to unity -- tawhid -- characteristic of the prophet.  Revealed to Ibn  ‘Arabi in a single night at age sixty-five, The Wisdom of the Prophets is a brilliant, often insightful book which is without parallel in the history of Sufism.

Ibn ‘Arabi‘s thought, at once radical and comprehensive, scriptural and mystical, inspired defenders and detractors, sparking a debate over “Unity of Being” and “Unity of Witness” that relates to the fundamental question:  How does one feel, think, act, and pray as a Muslim?

Ibn ‘Arabi’s ideas represent and culminate the third major phase of Sufi thought.  In the first phase, thinkers such as Rabi‘a, Junayd, and Bistami articulated the Sufi concept of mystical experience as the passing away of the human ego-self (nafs) and a Sufi way of life centered in that experience, and a Sufi affirmation of divine union as the immersion of human consciousness in one divine beloved to the point of obviousness to all other things.  In the second phase, represented by Sulami, Sarraj, Makki, Qushayri, and al-Ghazali, the Sufi experience of mystical union and the Sufi way of life were more explicitly integrated with ritual Islam and Islamic theology. 

With Ibn ‘Arabi, mystical union becomes not only the central moment in the affirmation of divine union and in the life of the Sufi, but it also becomes the central event within mystical language as well, an event that fundamentally transforms all language concerned with ultimate reality, reconfiguring and sometimes shattering the normal dualisms of subject and object, human and divine, before and after, self and other.

Ibn ‘Arabi’s writings mirror his philosophy of “perpetual transformation.”  His works continually move through the discourses of law, comparative philosophy, Islamic theology, esoteric sciences (alchemy, astrology, number symbolism, and talismans), meditative practice, Qur‘anic interpretation, hadith sciences, theory of prophecy, and sainthood.  Rather than forming a system, and certainly not forming a static philosophy of “oneness of reality” as the “sum” of all things (a conception that was due to later systematizers and followers of Ibn ‘Arabi), his work resists closure and analysis by linear development.  Like a moving picture made up of separate frames, it is the moving image that is meaningful, not the series of static frames.  This method of writing is a perfect reflection of the dynamism of Ibn ‘Arabi’s philosophy.

Ibn ‘Arabi’s thinking has been labeled as “theosophy,” but its originality and most lasting contribution are in the domain of apophatic thought, sometimes called “negative theology” (having to do with matters that are inexpressible).  As with the other practitioners of apophatic thinking, Ibn ‘Arabi begins from a critique of any attempt to refer to or name the transcendent, and ends with a dialectically simultaneous affirmation of absolute transcendence and absolute immanence.  Ibn ‘Arabi’s positions are grounded in previous controversies of scholastic theology (kalam).  After several centuries of growth, Islamic theology had divided into hundreds of schools of thought, all seeking to harmonize the absolute oneness of the Deity with the various attributes (ninety-nine attributes in the Qur‘an) ascribed to it.  Are these attributes (“the hearer,” “the seer,” “the compassionate,” and so forth) the same as the essence of the Deity?  If so, then the Deity has a plurality of eternal powers.  If the attributes are not co-eternal, then the deity is subject to accident and change, in a state of not-hearing in one instant, for example, and hearing in the next.

The quandary was vividly dramatized in the debate over a hadith (a saying of the Prophet Muhammad), parallel to a passage in Genesis, in which the Deity is said to have created Adam “in his image.” If the “his” refers to the Deity, then how is one to conceive of a transcendent, infinite Deity confined to an “image”?  Some theologians responded that the “his” must refer to Adam, to Adam’s being made as a full human, rather than going through a period of gestation, for example.   The Deity transcends all images.  Ibn ‘Arabi’s solution to this dilemma was to combine the Sufi concept of mystical union with his concept of the “complete human being.”  Adam, as the symbol of the complete human, that is, of archetypal human consciousness, is the mirror through which the Deity reveals its own attributes to itself, and the prism through which its undifferentiated unity is refracted into the various attributes.

The attributes of the Deity do not exist in themselves, nor are they purely categories of human imagination.  They are actualized only at the point that the mirror of human consciousness is polished and the reflections in it become visible.  By combining cosmic and the individual, macrocosm and microcosm, Ibn ‘Arabi treats this polishing of the mirror as any human’s “passing away” in union with the divine beloved.  When the Sufi, following the Sufi path outlined by Qushayri and Rabi‘a, achieves a point where his or her ego-self is annihilated, then the Deity reveals itself in the polished mirror of that Sufi’s heart.  At this point, to paraphrase the crucial hadith of mystical union, the Deity becomes the hearing with which he hears, the seeing with which he sees, the hands with which he touches, the feet with which he walks, the tongue with which he speaks. 

In dialectical terms, this “polishing of the mirror” is a co-creation in which both the Deity and human (as manifested entities endowed with form and categories) are created in the polished mirror of the complete human being.  A lord cannot exist without a servant, a creator Deity cannot exist without a creation in which it manifests itself and reflects itself.  Ultimate reality, what Ibn ‘Arabi calls the identity of self of the Real (dhat al-haqq), lies beyond all such dualisms.  The antecedent of “his” in “in his image” is neither the Deity by itself nor Adam by himself, but the Deity-human at the moment of the mystical union.  The image occurs within the polishing of the mirror when the Deity’s image is revealed and prismatically refracted in its attributes within the polished mirror of the human heart. 

From the perspective of eternity, this self-revelation always has occurred.  However, from the perspective of time, it is ephemeral.  It cannot be possessed.  Ibn ‘Arabi takes the dynamic notion of “the moment” as developed by earlier Sufis such as Qushayri and makes it the centerpiece of his mystical dialectic.  Quoting a Qur‘anic passage that refers to the Deity as being in every moment in a different condition, Ibn ‘Arabi states that the image of the eternal and infinite when it occurs in time is in a state of perpetual transformation.  In every moment the image changes.  Each image is formed by the linguistic, conceptual, philosophical, and psychological categories of the persons in which it appears.  Each is a valid manifestation of the Deity.

The central intellectual error, the cause of religious and philosophical disputes and violence, is the attempt to “bind” the Deity into a particular fixed image.  The human analytical intellect functions according to the principle of binding.  It constructs both grammar and logic according to bound or delimited categories: self and other, subject and predicate, before and after, here and there.  When the binding categories of language and logic are applied to the Deity, an image of the Deity is formed.  This image is valid -- but only “for the moment.”

When the human being clings to the image and reifies it, however, “binding” leads to idolatry.  The most disastrous idolatry of all occurs when people bind the Deity into their own affirmations of its transcendence.  In his critique of the Qur‘anic Noah, who called upon God to annihilate the idolaters, Ibn ‘Arabi suggests that Noah himself “bound” the Deity into the idol of the “beyond the world,” an

image just as limiting (by marking of the Deity from the world) as the polytheists' images of the Deity “within” their images of stones and wood.  The unlimited must simultaneously be beyond all things, within all things, other than all things, and identical with all things. This critique applies to Sufis as well as to those who are tempted to bind the Deity into a particular station, vision or experience.

The intellectual activity of binding, therefore, must be complemented by perpetual transformation (taqallub).  The polished mirror of the human heart -- as locus not of emotion, but of this higher knowledge -- is capable of every form.  This phrase “capable of every form” becomes the central concept in Ibn ‘Arabi’s famous collection of love poetry, Interpreter of Desires, a volume that together with a later commentary plays upon that creative tension -- so important in Sufi thought -- between love poetry and philosophical analysis.  Ibn ‘Arabi evokes the classical motif of the lover’s meditation on the lost beloved and his dwelling upon the beloved’s departure with the women of her tribe and the “stations” along their journey away from the poet.

For Ibn ‘Arabi the beloved and the women of her tribe are aligned with the ephemeral images or manifestations of the Real.  The movement toward the beloved (symbolized by the movement of the pilgrim through the stations of the hajj, the pilgrimage to Mecca) are identical to the movements of the divine manifestations away from the human knower. The human being who accepts the condition of fundamental humanity is thus in a state of continual joy and continual sorrow.   In every moment he passes away in union with the divine beloved, the beloved appears in the reflection of the polished mirror of his heart, and -- most importantly -- the human accepts the immediate disappearance of that image so that it can be replaced by a new image.  The angels who objected to the creation of Adam, a creature who could “spill blood and cause corruption” (Qur‘an, Sura 2:30-33), failed to understand this notion of the role of humanity as the locus of a continuing kaleidoscope of divine manifestation.

When the mystic achieves this state of perpetual transformation, he or she is able to participate fully in the perpetual co-creation.  In a Sufi appropriation and transformation of the metaphysics of scholastic theology, the world is annihilated and re-created in every moment.  However, instead of the re-creation of the objective world by an independent creator Deity -- as we find in scholastic theology -- the Sufi re-creation is the mutual construction of the divine attributes and human categories within the polished mirror of the human heart, a construction that is renewed in each moment (waqt).

Different people have moments of different lengths. Some never achieve an image of reality.  Some achieve one in a lifetime and hold on to it with dogmatic fervor.  Some achieve one in a year, some in a month.  In a remarkable parallel to the dynamist notion of transcendence and immanence, Ibn ‘Arabi, emphasizes the continual creation of the divine image in every new moment, a creation that simultaneously always has occurred and always is occurring.  Ibn ‘Arabi identifies the eternal “breath of the compassionate” by which Allah breathed spirit into his creation, through Adam, with the breaths of the individual Sufi.  The goal of Sufi meditation and annihilation in mystical union is to make “his/His moment his/His breath.”  The alternate pronouns show that the referent at any moment is both the divine and the human as they mutually construct one another within the polished mirror and prism.  Ibn ‘Arabi also speaks of the divine as revealing it(self) to it(self) through it(self), again fusing the two possible pronouns of the pronoun (reflexive and non-reflexive) into one.  When Ibn ‘Arabi asks who reveals whom in whom and through whom, he stresses the transformation of categories of reflexive and non-reflexive, self and other, at the moment of mystical union.

Ibn ‘Arabi proclaimed that the heart capable of every form can receive and affirm all valid manifestations: the Torah, the Qur‘an, the Christian monk’s cell, the abode of idol, and the meadow of gazelles.  Wherever the “caravan of love” leads, Ibn ‘Arabi writes in his most famous poem from the Interpreter of Desires, that is his religion, his faith.  This famous statement is not a call for tolerance, a weak virtue in which one agrees to ignore other beliefs or to allow them to exist.  Rather, it is a call for a complete immersion in and acceptance of all manifestations of reality. 

Such acceptance is perpetually both critical and self-critical of the ways in which delimited images of ultimate realtiy can be reified and idolized.  The heart capable of every form is a conception of a knowing faculty that is dialectical in the sense of seeing each manifestation as the abode of divine immanence which simultaneously points to the Real’s transcendence of all images.  It is also dynamic in that the joy of receiving one manifestation is accompanied by the sorrow at losing the previous manifestation, a joy and a sorrow that are ultimately part of the one experience of mystical union, perpetually re-enacted in each moment.

Ibn ‘Arabi’s thought was systematized by later followers, and throughout the period of classical Islam, the influence of Ibn ‘Arabi was central.  In the modern period that influence came under attack from some modernists who were influenced by postivist Western ways of thinking and by dogmatists such as the Wahhabis of Saudi Arabia (where Ibn ‘Arabi’s works are banned).  In recent years there has been a strong worldwide resurgence of interest in Ibn ‘Arabi, -- “The Grand Master” (al-shaykh al-akbar) of Islamic mystical philosophy. 

In addition to his mystical treatises, Ibn ‘Arabi is also known for his mystical odes.  In these odes, Ibn ‘Arabi, like all Sufis, expresses his longing for Union with God in terms of passionate human love.  Many critics have been uncertain whether his poetry is in fact religious or erotic, a difficulty also encountered in the poetry of Hafiz.  The philosophy of Ibn ‘Arabi’s poetry appears to combine, as does that of most Sufi poets, elements of Muslim Orthodoxy, Manichaeanism, Gnosticism, neo-Platonism and Christianity.  Later Sufi poets, particularly Persians, can scarcely be called Muslims at all.  Their beliefs appear to coalesce into an indefinite pantheism.

Some critics have credited Ibn ‘Arabi with making the Muwashshah into a respectable literary form.  This is a type of poem, apparently native to Moorish Spain, which ends with a couplet in the colloquial language, and sometimes even in Spanish.  The Muwashshah was long despised by Arab literary circles, but after Ibn ‘Arabi established it, many of the finest love poems in Arabic literature came to be written in the Muwashshah form.

Ibn al-'Arabi see Ibn al-‘Arabi, Muhyi‘l-Din al-Ta‘i
Muhyi'l-Din al-Ta'i ibn al-'Arabi see Ibn al-‘Arabi, Muhyi‘l-Din al-Ta‘i
Muhyi'd-din ibn 'Arabi see Ibn al-‘Arabi, Muhyi‘l-Din al-Ta‘i
Shaykh al-Akbar, al- see Ibn al-‘Arabi, Muhyi‘l-Din al-Ta‘i
Ibn 'Arabi see Ibn al-‘Arabi, Muhyi‘l-Din al-Ta‘i
"The Grand Master" see Ibn al-‘Arabi, Muhyi‘l-Din al-Ta‘i


Ibn al-Ash‘ath
Ibn al-Ash‘ath (ʿAbd ar-Raḥmān ibn Muḥammad ibn al-Ashʿath)    (d. 704).  Descendant of a noble Kindi family of the Hadhramaut, who became famous for his rebellion against al-Hajjaj, the governor of Iraq.

Ibn al-Ash'ath was a Umayyad general who became celebrated as leader of a revolt (ad 699–701) against the governor of Iraq, al-Ḥajjāj. A member of the noble tribe of Kindah of the old aristocracy, Ibn al-Ashʿath was at first friendly toward the Umayyad authorities but then began to smart under the governance of the plebeian administrators. Styling himself Nāṣir al-muʾminīm (Helper of the Believers) in opposition to the Umayyad and other “bad” Muslims, he slowly became so estranged from al-Ḥajjāj that a clash of wills led to open revolt.

In 699, al-Ḥajjāj dispatched a crack force of Kūfans and Basrans, known as the Peacock Army, to put down a rebellion in Kābulistān (in present day Afghanistan). After an initial invasion of Kābulistān, Ibn al-Ashʿath, the commanding general, decided to wait until spring before continuing his campaign. Al-Ḥajjāj pressed for immediate action, and the dispute led to a revolt by Ibn al-Ashʿath and his troops.

Ibn al-Ashʿath moved slowly westward into Iraq, gathering support from both Arabs and non-Arabs along the way and engaging in two battles, one a victory and one a mild setback, forcing him to withdraw from Basra to Kūfah.

Al-Ḥajjāj, having received in the meantime a steady stream of Syrian reinforcements from the caliph ʿAbd al-Malik ibn Marwān, confronted Ibn al-Ashʿath’s superior army of 200,000 at Dayr al-Jamājim, outside Kūfah. Negotiations were initiated by the caliph’s agents, who offered the rebels the dismissal of al-Ḥajjāj, equal pay with their Syrian counterparts, and a governorship for Ibn al-Ashʿath. The Iraqis, however, rejected the proposals and were defeated in battle in September 701. The last of the rebellion was finally put down in October, when al-Ḥajjāj destroyed the Iraqi army in a violent battle at Maskin, on the Shaṭṭ ad-Dujaylah. The defeated Iraqis fled to Sijistān, eventually surrendering to the Syrians, while Ibn al-Ashʿath took refuge in Kābul.

Ibn al-Ash'ath either was murdered or committed suicide in 704.

'Abd ar-Rahman ibn Muhammad ibn al-Ash'ath see Ibn al-Ash‘ath
Nasir al-mu'minim see Ibn al-Ash‘ath
"Helper of the Believers" see Ibn al-Ash‘ath


Ibn al-‘Assal
Ibn al-‘Assal.  Name of a Coptic family of Egypt, also named Awlad al-‘Assal, whose members rose to wealth and high station at the Ayyubid court during the thirteenth century.  Their position reveals the loyalty of the Copts to the reigning dynasty and their hostility to the Crusaders, who considered them schismatics.  The literary figures were al-Safi, al-As‘ad and al-Mu‘taman.
Awlad al-'Assal see Ibn al-‘Assal.


Ibn al-Athir
Ibn al-Athir. Name borne by a number of apparently unrelated families, which was given great luster by three brothers from Jazirat ibn ‘Umar: (1) Majd al-Din (1149-1210), who, living at  Mosul, was the author of a collection of hadith which became a much used standard reference work, and of a dictionary of less common words and meanings in the Prophetic traditions, which has been incorporated in Ibn Manzur’s famous dictionary The Language of the Arabs; (2) ‘Izz al-Din (1160-1233) who, living at Mosul, became famous for his annalistic history from the beginning of the world to the year 628, called al-Kamil; and (3) Diya‘ al-Din (1163-1239) who obtained the title of vizier, and lived mainly at Mosul.  The works of Diya' al-Din are all concerned with literary criticism.

Abu al-Hassan Ali ibn Muhammad ibn Muhammad, better known as Ali 'Izz al-Din Ibn al-Athir al-Jazari (1160- 1233) was an Arab Muslim historian born in Cizre, a town in present-day Şırnak province in south-eastern Turkey, from the Ibn Athir family. He was born in Turkey Jazirat Ibn Umar.

He spent a scholarly life in Mosul, but often visited Baghdad. He was a Kurd, therefore for a time he was with Saladin's army in Syria and later lived in Aleppo and Damascus. His chief work was a history of the world, al-Kamil fi at-Tarikh (The Complete History). He includes some information on the Rus' people in his chronology.

The major works of 'Izz al-Din are:

    * The Complete History (Arabic: Al-Kamil fi al-Tarikh).
    * The Lions of the Forest and the Knowledge about the Companions (Arabic: Usud al-Ghabah fi Ma'rifah al-Sahabah).


Ibn al-Awwam
Ibn al-Awwam was an Arab agriculturist who flourished at Seville in Spain about the end of the 12th century. He wrote a treatise on agriculture in Arabic called Kitab al-Filaha (English: Book on Agriculture), which is the most comprehensive treatment of the subject in medieval Arabic, and one of the most important medieval works on the subject in any language. It was published in Spanish and French translations in the 19th century. 

His full name was Abu Zakariya Yahya ibn Muhammad ibn Ahmad ibn Al-Awwam Al-Ishbili. The appellation "Al-Ishbili" at the end of his name translates as "the Sevillean" i.e. from Seville. His dates of birth and death are not known. Nearly everything that is known about his biography is gleaned from his book. It appears that he was a large landowner whose interests lay exclusively with agricultural matters. It is clear that he did lots of hands-on growing and experimenting with a wide range of crops himself. It is also clear that he was well-read in the agricultural writings of his predecessors. He cites information from 112 different prior authors. His citations of prior authors have been analyzed with the following summary results: about 1900 direct and indirect citations altogether, of which 615 are to Byzantine authors (especially to the Geoponica of Cassianus Bassus), 585 are to Middle Eastern authors (especially to the Book of Nabataean Agriculture attributed to Ibn Wahshiyya), and 690 are to Andalusian Arabic authors (especially to Abu al-Khayr al-Ishbili and Ibn Hajjaj, who were two natives of Seville who each wrote a book about agriculture around year 1075, copies of which have survived only partly).

Ibn al-Awwam's treatise on agriculture is divided into thirty-four chapters. The first thirty chapters deal with crops and the last four deal with livestock. The first four chapters in the book deal successively with different types of soils, fertilizers, irrigation, and planning a garden layout. Then there are five chapters on growing fruit trees, including grafting, pruning, growing from cuttings, etc., and dozens of different fruit trees are treated individually. Later chapters deal with plowing, the choice of seeds, the seasons and their tasks, grain farming, leguminous plants, small allotments, aromatic plants and industrial plants. Again, many plants are treated individually. The treatise altogether covers the cultivation of 585 different plants.  One chapter is devoted to methods of preserving and storing foods after harvest, a topic which comes up intermittently elsewhere. The symptoms of many diseases of trees and vines are indicated, as are methods of cure. The chapters on livestock include discussion of the diseases and injuries to horses and cattle.



Ibn al-Banna‘
Ibn al-Banna‘ (d. 1079). Quranic scholar, traditionist and jurisconsult of the Hanbali school at Baghdad.  He kept a diary of day-to-day socio-religious life in Baghdad from an unknown date until 1077.

Ibn al-Bawwab
Ibn al-Bawwab (Ibn al-Sitri) (d. 1022).  Calligrapher of the Buyid period. He perfected the style of writing invented by the vizier Ibn Muqla.



Ibn al-Bawwāb was an Arabic calligrapher and illuminator who lived during the time of the Buyid dynasty. He most likely died around 1022 AD in Baghdad.

One of his greatest achievements was the perfection of the al-Khatt al-Mansub (literally, the well-proportioned script) style of Islamic calligraphy.


Ibn al-Sitri see Ibn al-Bawwab


Ibn al-Baytar
Ibn al-Baytar (Ibn al-Baitar) (Abu Muhammad Abdallah Ibn Ahmad Ibn al-Baitar Dhiya al-Din al-Malaqi) (circa, 1188 - 1248).  Botanist and pharmacologist of Malaga. In one of his works, he lists some 1400 samples.  This work had a considerable influence both outside and within the Islamic world.

Ibn al-Baytar was an Arab scientist, botanist, pharmacist and physician. He is considered one of the greatest scientists of Al-Andalus and is believed to be one of the greatest botanists and pharmacists of the Islamic Golden Age and Muslim Agricultural Revolution.

Born in the Andalusian city of Málaga at the end of the 12th century, he learned botany from the Málagan botanist Abu al-Abbas al-Nabati with whom he started collecting plants in and around Spain. Al-Nabati was responsible for developing an early scientific method, introducing empirical and experimental techniques in the testing, description and identification of numerous materia medica, and separating unverified reports from those supported by actual tests and observations.

In 1219, Ibn al-Baytar left Málaga to travel in the Islamic world to collect plants. He travelled from the northern coast of Africa as far as Anatolia. The major stations he visited include Bugia, Constantinople, Tunis, Tripoli, Barqa and Adalia.

After 1224, he entered the service of al-Kamil, an Ayyubid Sultan, and was appointed chief herbalist. In 1227 al-Kamil extended his domination to Damascus, and Ibn al-Baitar accompanied him there which provided him an opportunity to collect plants in Syria. His researches on plants extended over a vast area including Arabia and Palestine. He died in Damascus in 1248.

Ibn al-Baytar’s major contribution is Kitab al-Jami fi al-Adwiya al-Mufrada, which is considered one of the greatest botanical compilations in history, and was a botanical authority for centuries. It was also a pharmacopoeia (pharmaceutical encyclopedia) and contains details on at least 1,400 plants, foods, and drugs, 300 of which were his own original discoveries. His work was translated into Latin in 1758 and was being used in Europe up until the early 19th century. The book also contains references to 150 other previous Arabic authors as well as 20 previous Greek authors.

Ibn Al-Baytar’s second major work is Kitab al-Mlughni fi al-Adwiya al-Mufrada which is an encyclopedia of Islamic medicine, which incorporates his knowledge of plants extensively for the treatment of various ailments, including diseases related to the head, ear, eye, etc.

In cancer therapy, Ibn al-Baytar discovered the earliest known herbal treatment for cancer: "Hindiba", a herbal drug which he identified as having "anti-cancer" properties and which could also treat other tumors and neoplastic disorders. After recognizing its usefulness in treating neoplastic disorders, Hindiba was patented in 1997 by Nil Sari, Hanzade Dogan, and John K. Snyder.



Abu Muhammad Abdallah Ibn Ahmad Ibn al-Baitar Dhiya al-Din al-Malaqi see Ibn al-Baytar
Ibn al-Baitar see Ibn al-Baytar


Ibn al-Bilarish
Ibn al-Bilarish.  Physician and pharmacist of Almeria during the twelfth century.


Ibn al-Daya
Ibn al-Daya.  Historian from Baghdad during the ninth century.  He wrote a biography of Ahmad ibn Tulun and a work containing stories about rewards for good deeds, punishment for evil deeds, and timely escape from difficult situations.


Ibn al-Dayba‘
Ibn al-Dayba‘ (1461-1537).  Historian and religious scholar of Zabid in Yemen.  His history of the town of Zabid is current to 1518.


Ibn al-Dubaythi
Ibn al-Dubaythi (Djamal al-Din Abu Muhammad bin Yahya bin Said) (June 30, 1163 - October 7, 1239).  Iraqi historian.  He is known for his History of Baghdad, containing biographies of people who died after 1166.  His History of Wasit was not preserved.

Djamal al-Din Abu Muhammad bin Yahya bin Said known as Ibn al-Dubaythi, was an Arab historian born in Wasit and died in Baghdad.


Ibn al-Faqih
Ibn al-Faqih. (Ibn al-Faqih al-Hamadhani(Persianابن فقیه الهمذانی‎)  Persian author of a geography written in Arabic during the ninth century.  In his only surviving work The Book of the Countries (Concise Book of Lands), he describes his native town Hamadan and the countries of Iran, Arabia, Iraq, Syria, Egypt, Rum, Jazira, Central Asia, Nubia, Abyssinia, North Africa, al-Andalus and Sudan are given merely a brief mention.

Ibn al-Faqih al-Hamadhani became famous for his Mukhtasar Kitab al-Buldan (Concise Book of Lands). He was noted for his comparison of the customs, food diets, codes of dress, rituals, along with the flora and fauna of China and India.

Ibn al-Faqih al-Hamadhani see Ibn al-Faqih.


Ibn al-Farid
Ibn al-Farid (Ibn Farid) (`Umar ibn `Alī ibn al-Fārid) (1181-1235).  Sufi poet of Cairo.  His tomb beneath al-Muqattam is still frequented.  His diwan is one of the most original in Arabic literature.

Ibn al-Farid was born in Cairo, lived for some time in Mecca and died in Cairo. His poetry is entirely Sufic, and he was deemed the greatest mystic poet of the Arabs. Some of his poems are said to have been written in ecstasies.

The poetry of Shaykh Umar Ibn al-Farid is considered by many to be the pinnacle of Arabic mystical verse, though surprisingly he is not widely known in the West. (Rumi and Hafiz, probably the best known in the West of the great Sufi poets, both wrote primarily in Persian, not Arabic.) Ibn al-Farid's two masterpieces are The Wine Ode, a beautiful meditation on the "wine" of divine bliss, and The Poem of the Sufi Way, a profound exploration of spiritual experience along the Sufi Path and perhaps the longest mystical poem composed in Arabic. Both poems have inspired in-depth spiritual commentaries throughout the centuries, and they are still reverently memorized by Sufis and other devout Muslims today.

Ibn al-Farid's father moved from his native town, Hama in Syria, to Cairo where Umar was born. Some sources say that his father was a respected farid (an advocate for women’s causes) and others say that his profession was the allocation of shares (furūḍ) in cases of inheritance. Whichever is the case, Ibn al-Farid's father was a knowledgeable scholar and gave his son a good foundation in belles lettres.

When he was a young man Ibn al-Farid would go on extended spiritual retreats among the oases, specifically the Oasis of the Wretches (Wadi al-Mustad'afin), outside of Cairo, but he eventually felt that he was not making deep enough spiritual progress. He abandoned his spiritual wanderings and entered law school studying in the shafi'i school of law.

Shaykh Umar Ibn al-Farid stayed in Mecca for fifteen years, but eventually returned to Cairo.

Upon Ibn al-Farid’s return to Cairo, he was treated as a Saint. He would hold teaching sessions with judges, viziers and other leaders of the city. While walking down the street, people would come up to him and crowd around him, seeking spiritual blessings (barakah) and try to kiss his hand (he would respond by shaking their hand). Ibn al-Farid became a scholar of Muslim law, a teacher of the hadith (the traditions surrounding the sayings and life of the prophet Muhammad), and a teacher of poetry.

Unlike many other respected poets of the day such as Ibn Sana al-Mulk, Ibn Unayn, Baha al-Din Zuhayr and Ibn Matruh, Ibn al-Farid refused the patronage of wealthy governmental figures which would have required him to produce poetry for propaganda, preferring the relatively humble life of a teacher that allowed him to compose his poetry of enlightenment unhampered. One time al-Malik al-Kamil, who was the Ayubbid sultan at that time, liked some of his odes so much that he sent the poet an exorbitant amount of money and offered to build a shrine for him. Ibn al-Farid denied both the money and the offer of the shrine, choosing to trust in God to supply for his needs. His position as a teacher at the Azhar mosque allowed him to provide for his family, which included three children.

Ibn al-Farid died in the Azhar mosque. He was buried in Qarafah cemetery at the foot of Mount Muqqattam under the al-Arid mosque. The burial was postponed because the grave was not completely dug. Some said this was to “chastise him for claiming such a high status in love” while others said it was “merely the last indignity that one of God’s chosen must suffer from the contingencies of the world below.”

During the later part of his life, Ibn al-Farid was known to enter into spiritual raptures known as jadhabat in Arabic, a common practice in Sufism.

Normally described as being handsome, his son wrote that when a mystical state overcame him, his face would increase in beauty and brightness. Sweat would pour from his body and collect at the ground beneath his feet, which was a result of jumping and dancing. He would also take forty-day fasts, during which he would neither eat, drink nor sleep.

During one particular ecstasy, the Shaykh screamed out and danced in the middle of the market bazaar. Others in the market began to join in and dance with them, causing a commotion with some of them falling on the ground. Ibn al-Farid threw off all of his clothes, an act which members of the crowd repeated. The crowd carried the Shaykh in his underwear to the Azhar mosque where he remained in this state for some days afterward.

Ibn al-Farid claimed to see many things happen that could be considered to be out of this world. He wrote of a lion kneeling down to him and asking him to ride. He also wrote of seeing a man descending a mountain, floating without using his feet. He also claimed to have conversed with Muhammad in a dream.

Ibn al-Farid’s son Kamal al-Din Muhammad described his ecstasies or trances as sometimes lasting ten consecutive days without eating, drinking, moving, speaking or hearing outside noises. He would alternately stand, sit, lie on his side and “throw himself down on his side.” When he came to, his first words would be a dictation of the verse God had given him.

Every Friday, Cairenes gather at Ibn al-Farid's tomb to listen to readings of his poems.

The was once a Sufi order in Egypt in the sixteenth called “al-Fāriḍīyah”. It supposedly originated from ibn al-Farid, but is no longer in existence.

Due to the subject matter of his poems and the beauty of the verse, Ibn al-Farid later became referred to as "sultan al’-ashiqin" (“the sultan of lovers”).
Ibn Farid see Ibn al-Farid
'Umar ibn 'Ali ibn al-Farid see Ibn al-Farid


Ibn al-Furat
Ibn al-Furat.  Name of a number of persons who held the offices of secretary or vizier under the ‘Abbasid caliphs or the Ikhshidid amirs in the ninth through tenth centuries.  The members of this Shi‘a family worth mentioning are: (1) Abu‘l-‘Abbas (d.904), who was commissioned to restore the state finances; (2) Abu‘l-Hasan (855-924) who was several times the vizier of the ‘Abbasid Caliph al-Muqtadir; was a prominent financier and politician; and a man of great culture, but too often concerned primarily with increasing his own wealth; (3) Abu‘l-Fath (Ibn Hinzaba) (d.938) who was the vizier for a few months in 932; and (4) Abu‘l-Fadl (921-1001) who was the vizier of the Ikhshidids of Egypt and facilitated the entry of the Fatimid troops into that country.  He had the reputation of a patron of poets and scholars but also that of an eccentric.


Ibn al-Furat, Nasir al-Din
Ibn al-Furat, Nasir al-Din (Nasir al-Din ibn al-Furat) (1334-1405).  Egyptian historian.  He was the author of a vast History of the Dynasties and Kings, of which only the volumes covering the years after 1106 were finished completely.  Its value rests on its being very detailed and on the wide range of its sources.
Nasir al-Din ibn al-Furat see Ibn al-Furat, Nasir al-Din


Ibn al-Fuwati
Ibn al-Fuwati (1244-1323).  Historian and librarian from Baghdad.  He did much copying of manuscripts and wrote large works on history and biography, most of which have been lost.  Preserved are his large biographical dictionary arranged according to nicknames and honorary titles, a first-class reference tool, and a centennial history which is of very great interest for everyday life in Baghdad.

Ibn al-Fuwati was an Iraqi historian who wrote a great deal, but whose works have mostly been lost. However, large portions of his biographical dictionary Madjma' al-adab fi mu'djam al-alqab were preserved. He was active in Iraq and Azerbaijan, and his most famous teaching position was at the Madrasa Mustansiriya.


Ibn al-Habbariyya
Ibn al-Habbariyya (d. 1115).  Arab poet.  A great poetic talent, he rendered the Kalila wa-Dimna into verse.


Ibn al-Haddad
Ibn al-Haddad. Andalusian poet from Cadix.  One of his love poems is dedicated to a Coptic Christian nun in Egypt, whom he had seen while about to embark upon the pilgrimage.


Ibn al-Hajib, Jamal al-Din
Ibn al-Hajib, Jamal al-Din (Jamal al-Din ibn al-Hajib) (c. 1174-1249).  Maliki jurist and grammarian.  He owes his reputation to two short works on morphology and syntax. 
Jamal al-Din ibn al-Hajib see Ibn al-Hajib, Jamal al-Din


Ibn al-Hajj
Ibn al-Hajj.  Name of several persons, in particular of the Maliki jurist Abu ‘Abd Allah al-Fasi (Mohammed ibn Mohammed ibn Mohammed Abu Abdallah ibn al-Hajj al-Abdari al-Maliki al-Fassi).  The name also refers to four grammarians (of the eleventh, thirteenth and nineteenth centuries), two Andalusian men of letters (of the fourteenth century) and a poet and theologian who wrote a commentary on al-Sanusi.  Another Ibn al-Hajj al-Fasi (1760-1817) was one of the most outstanding scholars of the reign of the Filali Sharif of Morocco Mawlay Abu‘l-Rabi‘ Sulayman.


Ibn al-Hajj
Moḥammed ibn Hajj al-Abdari al-Fassi (or Mohammed Ibn Mohammed ibn Mohammed Abu Abdallah Ibn al-Hajj al-Abdari al-Maliki al-Fassi) was a Moroccan Maliki fiqh scholar and theologian writer. Originally from Fes, he would finish his life in Egypt where he died in 1336. He is most remembered for his famous book "al-Madkhal".

Ibn al-Hajj studied under many scholars of high standing in various cities and provinces, including Tunis, Al-Qairawan, Alexandria, Cairo, in addition to Madinah and Makkah. 

Ibn al-Hajj al-Abdari wrote Madkhal Ash-Shara Ash-Shareef Ala Al-Mathahib (Introduction to Islamic Jurisprudence According to Schools of Thought). The book was published in 4 volumes of over 300 pages each and addresses many different subjects. In the first volume, Ibn al-Hajj includes 22 chapters, each addressing one question where practice is at variance with Islamic teachings. He scrutinizes the practice and points out the proper way to follow. Thus, there are chapters on intention, pursuing knowledge, prayer, the position of a mosque as a place of education, offering prayers at home, the behavior of scholars during scholarly debate, etc. The second volume has 62 chapters with a similar number of questions, including the Prophet’s birthday, the position of Madinah, the manners to be followed by students, women’s behavior, etc. The whole book is written in this way, without any particular thread for the arrangement of its chapters and questions. It is not a book on fiqh in the usual sense, nor is it a book of education and its methods, or a book of hadith or Qur’anic commentary, but it includes something of all these disciplines. Ibn al-Hajj's views are very much influenced by al-Ghazali's Ihya’ ‘Ulum al-Din.  Ibn al-Hajj spent much of his life in Tunis and Egypt and, for some time, taught at the university of Fes, Al-Qarawiyyin.  He was buried in Qarafa (Egypt).

Ibn al-Hajj is noted for what he said about the developing concept of schools.  He said: "The schools should be in the bazaar or a busy street, not in a secluded place. ... It is a place for teaching, not an eating house, so the boys should not bring food or money. ... In the organization, a teacher must have a deputy to set the class in their places, also visitors according to their rank, to awaken the sleepers, to warn those who do what they ought not or omit what they ought to do, and bid them listen to the instruction. In class, conversation, laughing and jokes are forbidden."


Ibn al-Hajjaj
Ibn al-Hajjaj (c. 941-1001).  Arab poet of Baghdad in the time of the Buyids.  A wealthy man of affairs, Ibn al-Hajjaj showed a dual personality in his work.  On the one hand, he wrote traditional panegyrics, on the other, he did not respect anything, neither Islam, nor the most honorable persons, nor himself.


Ibn al-Hannat
Ibn al-Hannat (d. 1045).  Andalusian poet.  He is considered one of the greatest scholars of the early eleventh century in the field of Arabic language and literature.


Ibn al-Hawwas
Ibn al-Hawwas (d. c. 1064).   One of the Muslim commanders in Sicily.  He managed to remain lord of Agrigento, Castrogiovanni, and Castronuovo and defeated his brother-in-law Ibn al-Maklati.

Ibn al-Haytham
Ibn al-Haytham (Abu ‘Ali al-Hasan ibn al-Haytham) (Abū ʿAlī al-Ḥasan ibn al-Ḥasan ibn al-Haytham) (Alhazen) (Avennathan) (965 in Basra - c. 1039 in Cairo).  Arab mathematician known in the West as Alhazen or Avennathan.   He is considered to be Islam’s greatest scientist who devoted his life to physics, astronomy, mathematics, and medicine.  His treatise Optics, in which he deftly used experiments and advanced mathematics to understand the action of light, exerted a profound influence on many European natural philosophers.  In addition to his Latinized names of Alhazen and Avennathan, Ibn al-Haytham is sometimes called al-Basri.  He is also nicknamed Ptolemaeus Secundus ("Ptolemy the Second") or simply "The Physicist" in medieval Europe.

Abu ‘Ali al-Hasan ibn al-Haytham (commonly known as Alhazen, the Latinized form of his first name, al-Hasan) was born in Basra (Iraq) in 965.  He was given a traditional Muslim education, but at an early age he became perplexed by the variety of religious beliefs and sects, because he was convinced of the unity of truth.  When he was older, he concluded that truth could be attained only in doctrines whose matter was sensible and whose form was rational.  He found such doctrines in the writings of Aristotle and in natural philosophy and mathematics. 

By devoting himself completely to learning, Alhazen achieved fame as a scholar and was given a political post at Basra.  In an attempt to obtain a better position, he claimed that he could construct a machine to regulate the flooding of the Nile.  The Fatimid caliph al-Hakim, wishing to use this sage’s expertise, persuaded him to move to Cairo.  Alhazen, to fulfill his boast, was trapped into heading an engineering mission to Egypt’s southern border.  On his way to Aswan, he began to have doubts about his plan, for he observed excellently designed and perfectly constructed buildings along the Nile, and he realized that his scheme, if it were possible, would have already been carried out by the creators of these impressive structures.  His misgivings were confirmed when he discovered that the cataracts south of Aswan made flood control impossible.  Convinced of the impracticability of his plan, and fearing the wrath of the eccentric and volatile caliph, Alhazen pretended to be mentally deranged.  Upon his return to Cairo, he was confined to his house until al-Hakim’s death in 1021. 

Alhazen then took up residence in a small domed shrine near the Azhar mosque.  Having been given back his previously sequestered property, he resumed his activities as a writer and teacher.  He may have earned his living by copying mathematical works, including Euclid’s Stoicheia (c. fourth century B.C.T.; Elements) and Mathematike suntaxis (c.150; Almagest), and may also have traveled and had contact with other scholars.

The scope of Alhazen’s work is impressive.  He wrote studies on mathematics, physics, astronomy, and medicine, as well as commentaries on the writings of Aristotle and Galen.  He was an exact observer, a skilled experimenter, and an insightful theoretician.  He put these abilities to excellent use in the field of optics.  He has been called the most important figure in optics between antiquity and the seventeenth century.  Within optics itself, the range of his interests was wide. He discussed theories of light and vision, the anatomy and diseases of the eye, reflection and refraction, the rainbow, lenses, spherical and parabolic mirrors, and the pinhole camera (camera obscura).

Alhazen’s most important work was Kitab al-Manazir, commonly known as Optics.  Not published until 1572, and only appearing in the West in the Latin translation Opticae thesaurus Alhazeni libri vii, it attempted to clarify the subject by inquiring into its principles.  He rejected Euclid’s and Ptolemy’s doctrine of visual rays (the extramission theory, which regarded vision as analogous to the sense of touch).  For example, Ptolemy attributed sight to the action of visual rays issuing conically from the observer’s eye and being reflected from various objects.  Alhazen also disagreed with past versions of the intromission theory, which treated the visible object as a source from which forms (simulacra) issued.  The atomists, for example, held that objects shed sets of atoms as a snake sheds its skin; when this set enters the eye, vision occurs.  In another version of the intromission theory, Aristotle treated the visible object as a modifier of the medium between the object and the eye.  Alhazen found the atomistic theory unconvincing because it could not explain how the image of a large mountain could enter the small pupil of the eye.  He did not like the Aristotelian theory because it could not explain how the eye could distinguish individual parts of the seen world, since objects altered the entire intervening medium.  Alhazen, in his version of the intromission theory, treated the visible object as a collection of small areas, each of which sends forth its own ray.  He believed that vision takes place through light rays reflected from every point on an object’s surface converging toward an apex in the eye.

According to Alhazen, light is an essential form in self-luminous bodies, such as the sun, and an accidental form in bodies that derive their luminosity from outside sources.  Accidental light, such as the moon, is weaker than essential light, but both forms are emitted by their respective sources in exactly the same way: noninstantaneously, from every point on the source, in all directions, and along straight lines.  To establish rectilinear propagation for essential, accidental, reflected, and refracted radiation, Alhazen performed many experiments with dark chambers, pinhole cameras, sighting tubes, and strings.

In the first book of Optics, Alhazen describes the anatomy of the eye.  His description is not original, being based largely on the work of Galen, but he modifies traditional ocular geometry to suit his own explanation of vision.  For example, he claims that sight occurs in the eye by means of the glacial humor (what would be called the crystalline lens), because when this humor is injured, vision is destroyed.  He also uses such observations as eye pain while gazing on intense light and afterimages from strongly illuminated objects to argue against the visual-ray theory, because these observations show that light is coming to the eye from the object.  With this picture of intromission established, Alhazen faces the problem of explaining how replicas as big as a mountain can pass through the tiny pupil into the eye.

He begins the solution of this problem by recognizing that every point in the eye receives a ray from every point in the visual field.  The difficulty with this punctiform analysis is that, if each point on the object sends light and color in every direction to each point of the eye, then all this radiation would arrive at the eye in total confusion.  For example, colors would arrive mixed.  Simply put, the problem is a superfluity of rays.  To explain vision, each point of the surface of the glacial humor needs to receive a ray from only one point in the visual field.  In short, it is necessary to establish a one-to-one correspondence between points in the visual field and points in the eye.

To fulfill this goal, Alhazen notices that only one ray from each point in the visual field falls perpendicularly on the convex surface of the eye.  He then proposes that all other rays, those falling at oblique angles to the eye’s surface, are refracted and so weakened that they are incapable of affecting visual power.  Alhazen even performed an experiment to show that perpendicular rays are strong and oblique rays weak. He shot a metal sphere against a dish both perpendicularly and obliquely.  The perpendicular shot fractured the plate, whereas the oblique shot bounced off harmlessly.  Thus, in his theory, the cone of perpendicular rays coming into the eye accounts for the perception of the visible object’s shape and the laws of perspective.

Book 2 of Optics contains Alhazen’s theory of cognition based on visual perception, and book 3 deals with binocular vision and visual errors.  Catoptrics (the theory of reflected light) is the subject of book 4.  Alhazen here formulates the laws of reflection. Incident and reflected rays are in the same plane, and incident and reflected angles are equal.  The equality of the angles of incidence and reflection allows Alhazen to explain the formation of an image in a plane mirror.  As throughout Optics,  Alhazen uses experiments to help establish his contentions.  For example, by throwing an iron sphere against a metal mirror at an oblique angle, he found that the incident and reflected movements of the sphere were symmetrical.  The reflected movement of the iron sphere, because of its heaviness, did not continue in a straight line, as the light ray does, but Alhazen did not contend that the iron sphere is an exact duplicate of the light ray.

Alhazen’s investigation of reflection continues in books 5 and 6 of Optics.  Book 5 contains the famous “Problem of Alhazen”: For any two points opposite a spherical reflecting surface, either convex or concave, find the point or points on the surface at which the light from one of the two points will be reflected to the other.  Today it is known that the algebraic solution of this problem leads to an equation of the fourth degree, but Alhazen solved it geometrically by the intersection of a circle and a hyperbola.

Book 7, which concludes Optics, is devoted to dioptrics (the theory of refraction).  Although Alhazen did not discover the mathematical relationship between the angles of incidence and refraction, his treatment of the phenomenon was the most extensive and enlightening before that of Rene Descartes.  As with reflection, Alhazen explores refraction through a mechanical analogy.  Light, he says, moves with great speed in a transparent medium such as air and with slower speed in a dense body such as glass or water.  The slower speed of the light ray in the denser medium is the result of the greater resistance it encounters, but this resistance is not strong enough to hinder its movement completely.  Since the refracted light ray is not strong enough to maintain its original direction in the denser medium, it moves in another direction along which its passage will be easier (that is, it turns toward the normal).  This idea of the easier and quicker path was the basis of Alhazen’s explanation of refraction, and it is a forerunner of the principle of least time associated with the name of Pierre de Fermat.

Optics was Alhazen’s most significant work and by far his best known, but he also wrote more modest treatises in which he discussed the rainbow, shadows, camera obscura, and Ptolemy’s optics as well as spheroidal and paraboloidal burning mirrors.  The ancient Greeks had a good understanding of plane mirrors, but Alhazen developed an exhaustive geometrical analysis of the more difficult problem of the formation of images in spheroidal and paraboloidal mirrors.

Although Alhazen’s achievements in astronomy do not equal those in optics, his extant works reveal his mastery of the techniques of Ptolemaic astronomy.  These works are mostly short tracts on minor problems, for example, sundials, moonlight, eclipses, parallax, and determining the gibla (the direction to be faced in prayer).  In another treatise, he was able to explain the apparent increase in size of heavenly bodies near the horizon, and he also estimated the thickness of the atmosphere.

His best astronomical work, and the only one known to the medieval West, was Hay’at al-‘alan (tenth or eleventh century; on the configuration of the world).  This treatise grew out of Alhazen’s desire that the astronomical system correspond to the true movements of actual heavenly bodies.  He therefore attacked Ptolemy’s system, in which the motions of heavenly bodies were explained in terms of imaginary points moving on imaginary circles.  In his work, Alhazen tried to discover the physical reality underlying Ptolemy’s abstract astronomical system.  He accomplished this task by viewing the heavens as a series of concentric spherical shells whose rotations were interconnected.  Alhazen’s system accounted for the apparent motions of the heavenly bodies in a clear and untechnical way, which accounts for the book’s popularity in the Middle Ages.

Alhazen’s fame as a mathematician has largely depended on his geometrical solutions of various optical problems, but more than twenty strictly mathematical treatises have survived.  Some of these deal with geometrical problems arising from his studies of Euclid’s Elements, whereas others deal with quadrature problems, that is, constructing squares equal in area to various plane figures.  He also wrote a work on lunes (figures contained between the arcs of two circles) and on the properties of conic sections.  Although he was not successful with every problem, his performance, which exhibited his masterful command of higher mathematics, has rightly won for him the admiration of later mathematicians.

For most scientific historians, Alhazen was the greatest Muslim scientist, and Optics was the most important work in the field from Ptolemy’s time to Johannes Kepler’s.  Alhazen extricated himself from the limitations of such earlier theories as the atomistic, Aristotelian, and Ptolemaic and integrated what he knew about medicine, physics, and mathematics into a single comprehensive theory of light and vision.  Although his theory contained ideas from older theories, he combined these ideas with his new insights into a fresh creation, which became the source of a new optical tradition.

Alhazen's optical theories had some influence on Islamic scientists, but their main impact was on the West.  Optics was translated from Arabic into Latin at the end of the twelfth century.  It was widely studied, and in the thirteenth century, Witelo (also known as Vitellio) made liberal use of Alhazen’s text in writing his comprehensive book on optics.  Roger Bacon, John Peckham, and Giambattista della Porta are only some of the many thinkers who were influenced by Alhazen’s work.  Indeed, it was not until Kepler, six centuries later, that work on optics progressed beyond the point to which Alhazen’s ideas had taken the subject matter.  Indeed, it would not be going too far to say that Alhazen’s optical theories defined the scope and goals of the field from his day to ours.

Al-Haitham was one of the most eminent physicists, whose contributions to optics and the scientific methods are outstanding.  Ibn al-Haitham was born in 965 in Basra (in present day Iraq), and received his education in Basra and Baghdad.  He traveled to Egypt and Spain.  He spent most of his life in Spain, where he conducted research in optics, mathematics, physics, medicine and development of scientific methods.

Al-Haitham conducted experiments on the propagation

of light and colors, optic illusions and reflections.  He examined the refraction of light rays through transparent medium (air, water) and discovered the laws of refraction.  He also carried out the first experiments on the dispersion of light into its constituent colors.  In detailing his experiment with spherical segments (glass vessels filled with water) , he came very close to discovering the theory of magnifying lenses which was developed in Italy three centuries later.  It took another three centuries before the law of sines was proposed by Snell and Descartes.

Al-Haitham’s book Kitab al-Manazir was translated into Latin in the Middle Ages, as was also his book dealing with the colors of sunset.  He dealt at length with the theory of various physical phenomena such as the rainbow, shadows, eclipses, and speculated on the physical nature of light.  Virtually all of the medieval Western writers on optics based their optical work on al-Haitham’s Opticae Thesaurus.  His work also influenced Leonardo da Vinci and Johannes Kepler.  His approach to optics generated fresh ideas and resulted in great progress in experimental methods.

Al-Haitham was the first to describe accurately the various parts of the eye and gave a scientific explanation of the process of vision.  He contradicted Ptolemy’s and Euclid’s theory of vision that the eye sends out visual rays to the object of the vision.  According to al-Haitham, the rays originate in the object of vision and not the eye. 

Al-Haitham also attempted to explain binocular vision, and gave a correct explanation of the apparent increase in size of the sun and the moon when near the horizon.  He is known for the earliest use of the camera obscura.  Through these extensive researches on optics, al-Haitham came to be considered the Father of Modern Optics.

In al-Haitham’s writings, one finds a clear explanation of the development of scientific methods as developed and applied by the Muslims, the systematic observation of physical phenomena and their relationship to a scientific theory.  This was a major breakthrough in scientific methodology, as distinct from guess work, and placed scientific study on a sound foundation comprising systematic relationship between observation, hypothesis and verification.

His research in catoptrics focused on spherical and parabolic mirrors and spherical aberration.  He made the important observation that the ratio between the angle of incidence and refraction does not remain constant and investigated the magnifying power of a lens.  His catoptrics contains the important problem known as Alhazen’s problem.  It comprises drawing lines from two points in the plane of a circle meeting at a point on the circumference and making equal angles with the normal at that point.  This leads to an equation of the fourth degree.   Al-Hazen also solved the shape of an aplantic surface of reflection.

In his book Mizan al-Hikmah, al-Haitham discussed the density of the atmosphere and developed a relation between it and the height.  He also studied atmospheric refraction.  Al-Haitham discovered that the twilight only ceases or begins when the sun is nineteen degrees below the horizon and attempted to measure the height of the atmosphere on that basis.  He deduced the height of homogeneous atmosphere to be fifty-five miles.

Al-Haitham’s contribution to mathematics and physics is extensive.  In mathematics, he developed analytical geometry by establishing linkage between algebra and geometry.  In physics, he studied the mechanics of motion of a body and was the first to propose that a body move perpetually unless an external force stops it or changes its direction of motion.  This is strikingly similar to the first law of motion.  He has also discussed the theories of attraction between masses, and it appears that he was aware of the magnitude of acceleration due to gravity.

Alhazen wrote more than two hundred books, very few of which have survived.  His monumental treatise on optics has survived through its Latin translation.  During the Middle Ages, his books on cosmology were translated into Latin, Hebrew and other European languages.  Also, he wrote a book on the subject of evolution. 

Alhazen's influence on physical sciences in general, and optics in particular, has been held in high esteem and his ideas heralded in a new era in both theoretical and experimental optical research.  He wrote commentaries on Aristotle, Galen, Euclid and Ptolemy.  Beer and Medler, in their famous work Der Mond, named one of the surface features of the Moon after Alhazen.  It is the name of a ring shaped plain to the West of the hypothetical Mare Crisium.  Additionally, on February 7, 1999, an asteroid was discovered by S. Sposetti at Gnosca, Italy.  The asteroid was named 59239 Alhazen.

Alhazen, the great Muslim scientist, died in 1039 in Cairo, Egypt. 

Abu ‘Ali al-Hasan ibn al-Haytham see Ibn al-Haytham
Haithem, al- see Ibn al-Haytham
Alhazen see Ibn al-Haytham
Avennathan see Ibn al-Haytham
The First Scientist see Ibn al-Haytham
Father of Modern Optics see Ibn al-Haytham

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