The Renowned Scientists and Thinkers of Muslim Era
By Salahudin
A Glimpses of The Renowned Scientists and Thinkers of Muslim Era! "
ABU ABDULLAH AL-BATANI (858 - 929 A.D.)
Abu Abdallah Muhammad Ibn Jabir Ibn Sinan al-Battani al-Harrani was born around 858 A.D. in Harran, and according to one account, in Battan, a State of Harran. Battani was first educated by his father Jabir Ibn San'an al-Battani, who was also a well-known scientist. He then moved to Raqqa, situated on the bank of the Euphrates, where he received advanced education and later on flourished as a scholar. At the beginning of the 9th century, he migrated to Samarra, where he worked till the end of his life in 929 A.D. He was of Sabian origin, but was himself a Muslim.
Battani was a famous astronomer, mathematician and astrologer. He has been held as one of the greatest astronomists of Islam. He is responsible for a number of important discoveries in astronomy, which was the result of a long career of 42 years of research beginning at Raqqa when he was young. His well-known discovery is the remarkably accurate determination of the solar year as being 365 days, 5 hours, 46 minutes and 24 seconds, which is very close to the latest estimates. He found that the longitude of the sun's apogee had increased by 16o, 47' since Ptolemy. This implied the important discovery of the motion of the solar apsides and of a slow variation in the equation of time. He did not believe in the trapidation of the equinoxes, although Copernicus held it.
AL-Battani determined with remarkable accuracy the obliquity of the ecliptic, the length of the seasons and the true and mean orbit of the sun.
He proved, in sharp contrast to Ptolemy, the variation of the apparent angular diameter of the sun and the possibility of annular eclipses. He rectified several orbits of the moon and the planets and propounded a new and very ingenious theory to determine the conditions of visibility of the new moon. His excellent observations of lunar and solar eclipses were used by Dunthorne in 1749 to determine the secular acceleration of motion of the moon. He also provided very neat solutions by means of orthographic projection for some problems of spherical trigonometry.
In mathematics, he was the first to replace the use of Greek chords by sines, with a clear understanding of their superiority. He also developed the concept of cotangent and furnished their table in degrees.
He wrote a number of books on astronomy and trigonometry. His most famous book was his astronomical treatise with tables, which was translated into Latin in the l2th century and flourished as De scienta stellerum - De numeris stellerum et motibus. An old translation of this is available of the Vatican. His Zij was, in fact, more accurate than all others written by that time.
His treatise on astronomy was extremely influential in Europe till the Renaissance, with translations available in several languages. His original discoveries both in astronomy and trigonometry were of great consequence in the development of these sciences.
ABU RAIHAN AL-BIRUNI (973 - 1048 A.D.)
Abu Raihan Mohammad Ibn Ahmad al-Biruni was one of the well-known figures associated with the court of King Mahmood Ghaznavi, who was one of the famous Muslim kings of the 11th century A.D. Al-Biruni was a versatile scholar and scientist who had equal facility in physics, metaphysics, mathematics, geography and history. Born in the city of Kheva near "Ural" in 973 A.D ., he was a contemporary of the well-known physician Ibn Sina.
At an early age, the fame of his scholarship went around and when Sultan Mahmood Ghaznavi conquered his homeland, he took al-Biruni along with him in his journeys to India several times and thus he had the opportunity to travel all over India during a period of 20 years. He learnt Hindu philosophy, mathematics, geography and religion from the Pandits to whom he taught Greek and Arabic science and philosophy. He died in 1048 A.D. at the age of 75, after having spent 40 years in thus gathering knowledge and making his own original contributions to it.
He recorded observations of his travels through India in his well-known book Kitab al-Hind which gives a graphic account of the historical and social conditions of the sub-continent. At the end of this book he makes a mention of having translated two Sanskrit books into Arabic, one called Sakaya, which deals with the creation of things and their types, and the second, Patanjal dealing with what happens after the spirit leaves the body. His descriptions of India were so complete that even the Aein-i-Akbari written by Abu-al-Fadal during the reign of Akbar, 600 years later, owes a great deal to al-Biruni's book. He observed that the Indus valley must be considered as an ancient sea basin filled up with alluvials.
On his return from India, al-Biruni wrote his famous book Qanun-i Masoodi (al-Qanun al-Masudi, fi al-Hai'a wa al-Nujum), which he dedicated to Sultan Masood. The book discusses several theorems of astronomy, trigonometry, solar, lunar, and planetary motions and relative topics.
In another well-known book al-Athar al-Baqia, he has attempted a connected account of ancient history of nations and the related geographical knowledge. In this book, he has discussed the rotation of the earth and has given correct values of latitudes and longitudes of various places. He has also made considerable contribution to several aspects of physical and economic geography in this book.
His other scientific contributions include the accurate determination of the densities of 18 different stones. He also wrote the Kitab-al-Saidana, which is an extensive materia medica that combines the then existing Arabic knowledge on the subject with the Indian medicine. His book the Kitab-al-Jamahir deals with the properties of various precious stones. He was also an astrologer and is reputed to have astonished people by the accuracy of his predictions. He gave a clear account of Hindu numerals, elaborating the principle of position. Summation of a geometric progression apropos of the chess game led to the number:
1616-1 = 18,44,6,744,073,709,551,619.
He developed a method for trisection of angle and other problems which cannot be solved with a ruler and a compass alone. Al-Biruni discussed, centuries before the rest of the world, the question whether the earth rotates around its axis or not. He was the fist to undertake experiments related to astronomical phenomena. His scientific method, taken together with that of other Muslim scientists, such as Ibn al-Haitham, laid down the early foundation of modern science. He ascertained that as compared with the speed of sound the speed of light is immense. He explained the working of natural springs and artesian wells by the hydrostatic principle of communicating vessels. His investigations included description of various monstrosities, including that known as "Siamese" twins. He observed that flowers have 3,4,5,6, or 18 petals, but never 7 or 9.
He wrote a number of books and treatises. Apart from Kitab-al-Hind (History and Geography of India), al-Qanun al-Masudi (Astronomy, Trigonometry), al-Athar al-Baqia (Ancient History and Geography), Kitab al-Saidana (Materia Medica) and Kitab al-Jamahir (Precious Stones) as mentioned above, his book al-Tafhim-li-Awail Sina'at at-Tanjim gives a summary of mathematics and astronomy.
He has been considered as one of the very greatest scientists of Islam, and, all considered, one of the greatest of all times. His critical spirit, love of truth, and scientific approach were combined with a sense of toleration.
His enthusiasm for knowledge may be judged from his claim that the phrase [- Allah is Omniscient does not justify ignorance. -]
ABUL WAFA MUHAMMAD AL-BUZJANI (940 - 997 A.D.)
Abul Wafa Muhammad Ibn Muhammad Ibn Yahya Ibn Ismail al-Buzjani was born in Buzjan, Nishapur in 940 A.D. He flourished as a great mathematician and astronomer at Baghdad and died in 997/998 A.D. He learnt mathematics in Baghdad. In 959 A.D. he migrated to Iraq and lived there till his death.
Abul Wafa's main contribution lies in several branches of mathematics, especially geometry and trigonometry. In geometry, his contribution comprises solution of geometrical problems with opening of the compass; construction of a square equivalent to other squares; regular polyhedra; construction of regular hectagon taking for its side half the side of the equilateral triangle inscribed in the same circle; constructions of parabola by points and geometrical solution of the equations:
[ x4 =a and x4 + ax3 = b ]
Abul Wafa's contribution to the development of trigonometry was extensive. He was the first to show the generality of the sine theorem relative to spherical triangles. He developed a new method of constructing sine tables, the value of sin 30' being correct to the eighth decimal place.
He also developed relations for sine (a + b) and the formula:
2sin2 - a/2 -= 1-cos a, and sin a = 2 sin - a/2 cos - a/2
In addition, he made a special study of the tangent and calculated a table of tangents. He introduced the secant and cosecant for the first time, knew the relations between the trigonometric lines, which are now used to define them, and undertook extensive studies on conics.
Apart from being a mathematician, Abul Wafa also contributed to astronomy. In this field he discussed different movements of the moon, and discovered 'variation'. He was also one of the last Arabic translators and commentators of Greek works.
He wrote a large number of books on mathematics and other subjects, most of which have been lost or exist in modified forms. His contribution includes Kitab 'Ilm al-Hisab, a practical book of arithmetic, al-Kitab al-Kamil (the Complete Book), Kitab al-Handsa (Applied Geometry). Apart from this, he wrote rich commentaries on Euclid, Diophantos and al-Khawarizmi, but all of these have been lost. His books now extant include Kitab 'Ilm al-Hisab, Kitab al-Handsa and Kitab al-Kamil.
His astronomical knowledge on the movements of the moon has been criticized in that, in the case of 'variation' the third inequality of the moon as he discussed was the second part of the 'evection'..
But, according to Sedat, what he discovered was the same that was discovered by Tycho Brache six centuries later. Nonetheless, his contribution to trigonometry was extremely significant in that he developed the knowledge on the tangent and introduced the secant and cosecant for the first time; in fact a sizable part of today's trigonometry can be traced back to him.
ABU AL-NASR AL-FARABI (870 - 950 A.D.)
Abu Nasr Mohammad Ibn al-Farakh al-Farabi was born in a small village Wasij, near Farab in Turkistan in 259 A.H. (870 A.D.). His parents were originally of Persian descent, but his ancestors had migrated to Turkistan. Known as al-Phrarabius in Europe, Farabi was the son of a general. He completed his earlier education at Farab and Bukhara but, later on, he went to Baghdad for higher studies, where he studied and worked for a long time viz., from 901 A.D. to 942 A.D. During this period he acquired mastery over several languages as well as various branches of knowledge and technology. He lived through the reign of six Abbasid Caliphs. As a philosopher and scientist, he acquired great proficiency in various branches of learning and is reported to have been an expert in different languages.
Farabi traveled to many distant lands and studied for some time in Damascus and Egypt, but repeatedly came back to Baghdad, until he visited Saif al-Daula's court in Halab (Allepo). He became one of the constant companions of the King, and it was here at Halab that his fame spread far and wide. During his early years he was a Qadi (Judge), but later on the took up teaching as his profession. During the course of his career, he had suffered great hardships and at one time was the caretaker of a garden. He died a bachelor in Damascus in 339 A.H. /950 A.D. at the age of 80 years.
Farabi contributed considerably to science, philosophy, logic, sociology, medicine, mathematics and music. His major contributions seem to be in philosophy, logic and sociology and, of course, stands out as an Encyclopedist. As a philosopher, he may be classed as a Neoplatonist who tried to synthesize Platonism and Aristotelism with theology and he wrote such rich commentaries on Aristotle's physics, meteorology, logic, etc.
In addition to a large number of books on several other subjects embodying his original contribution, that he came to. be known as the 'Second Teacher' (al-Mou 'allim al-Thani) Aristotle being the First. One of the important contributions of Farabi was to make the study of logic more easy by dividing it into two categories viz., Takhayyul (idea) and Thubut (proof).
In sociology he wrote several books out of which Ara Ahl al-Madina al-Fadila became famous. His books on psychology and metaphysics were largely based on his own work. He also wrote a book on music, captioned Kitab al-Musiqa. He was a great expert in the art and science of music and invented several musical instruments, besides contributing to the knowledge of musical notes. It has been reported that he could play his instrument so well as to make people laugh or weep at will. In physics he demonstrated the existence of void.
Although many of his books have been lost, 117 are known, out of which 43 are on logic,11 on metaphysics, 7 on ethics, 7 on political science, 17 on music, medicine and sociology, while 11 are commentaries. Some of his more famous books include the book Fusus al-Hikam, which remained a text book of philosophy for several centuries at various centers of learning and is still taught at some of the institutions in the East. The book Kitab al-Ihsa al-Ulum discusses classification and fundamental principles of science in a unique and useful manner. The book Ara Ahl al-Madina al-Fadila 'The Model City' is a significant early contribution to sociology and political science.
Farabi exercised great influence on science and knowledge for several centuries. Unfortunately, the book Theology of Aristotle, as was available to him at that time, was regarded by him as genuine, although later on it turned out to be the work of some Neoplatonic writer. Despite this, he was regarded the Second Teacher in philosophy for centuries and his work, aimed at synthesis of philosophy and sufism, paved the way for Ibn Sina's work.
AL-FARGHANI (c. 860)
Abu'l-Abbas Ahmad ibn Muhammad ibn Kathir al-Farghani, born in Farghana, Transoxiana, was one of the most distinguished astronomers in the service of al-Mamun and his successors. He wrote "Elements of Astronomy" (Kitab fi al-Harakat al-Samawiya wa Jawami Ilm al-Nujum i.e. the book on celestial motion and thorough science of the stars), which was translated into Latin in the l2th century and exerted great influence upon European astronomy before Regiomontanus. He accepted Ptolemy's theory and value of the precession, but thought that it affected not only the stars but also the planets. He determined the diameter of the earth to be 6,500 miles, and found the greatest distances and also the diameters of the planets.
AL-Farghani's activities extended to engineering. According to Ibn Tughri Birdi, he supervised the construction of the Great Nilometer at al-Fustat (old Cairo). It was completed in 861, the year in which the Caliph al-Mutawakkil, who ordered the construction, died. But engineering was not al-Farghani's forte, as transpires from the following story narrated by Ibn Abi Usaybi'a.
Al-Mutawakkil had entrusted the two sons of Musa ibn Shakir, Muhammad and Ahmad, with supervising the digging of a canal named al-Ja'fari. They delegated the work to AL-Farghani, thus deliberately ignoring a better engineer, Sind ibn Ali, whom, out of professional jealousy, they had caused to be sent to Baghdad, away from al-Mutawakkil's court in Samarra. The canal was to run through the new city, al-Ja'fariyya, which al-Mutawakkil had built near Samarra on the Tigris and named after himself.
Al-Farghani committed a grave error, making the beginning of the canal deeper than the rest, so that not enough water would run through the length of the canal except when the Tigris was high. News of this angered the Caliph, and the two brothers were saved from severe punishment only by the gracious willingness of Sind ibn Ali to vouch for the correctness of al-Farghani's calculations, thus risking his own welfare and possibly his life.
As had been correctly predicted by astrologers, however, al-Mutawakkil was murdered shortly before the error became apparent. The explanation given for Al Farghani's mistake is that being a theoretician rather than a practical engineer, he never successfully completed a construction.
The Fihrist of Ibn al-Nadim, written in 987, ascribes only two works to AL-Farghani : ( l) "The Book of Chapters, a summary of the Almagest" (Kitab al-Fusul, Ikhtiyar al-Majisti) and (2) "Book on the Construction of Sun-dials" (Kitab 'Amal al-Rukhamat).
The Jawami, or 'The Elements' as we shall call it, was Al-Farghani's best-known and most influential work. Abd al-Aziz al-Qabisi (d. 967) wrote a commentary on it, which is preserved in the Istanbul manuscript, Aya Sofya 4832, fols. 97v-114v. Two Latin translations followed in the l2th century. Jacob Anatoli produced a Hebrew translation of the book that served as a basis for a third Latin version, appearing in 1590, whereas Jacob Golius published a new Latin text together with the Arabic original in 1669. The influence of 'The Elements' on mediaeval Europe is clearly vindicated by the presence of innumerable Latin manuscripts in European libraries.
References to it in mediaeval writers are many, and there is no doubt that it was greatly responsible for spreading knowledge of Ptolemaic astronomy, at least until this role was taken over by Sacrobosco's Sphere. But even then, 'The Elements' of Al-Farghani continued to be used, and Sacrobosco's Sphere was evidently indebted to it. It was from 'The Elements' (in Gherard's translation) that Dante derived the astronomical knowledge displayed in the 'Vita nuova' and in the 'Convivio'.
ABU HAMID AL-GHAZAL-[Algazel] (1058-1128 A.D.)
[Sociology, Theology, Philosophy. ]
Abu Hamid Ibn Muhammad Ibn Muhammad al-Tusi al-Shafi'i al-Ghazali was born in 1058 A.D. in Khorasan, Iran. His father died while he was still very young but he had the opportunity of getting education in the prevalent curriculum at Nishapur and Baghdad. Soon he acquired a high standard of scholarship in religion and philosophy and was honored by his appointment as a Professor at the Nizamiyah University of Baghdad, which was recognized as one of the most reputed institutions of learning in the golden era of Muslim history.
After a few years, however, he gave up his academic pursuits and worldly interests and became a wandering ascetic. This. was a process (period) of mystical transformation. Later, he resumed his teaching duties, but again left these. An era of solitary life, devoted to contemplation and writing then ensued, which led to the author- ship of a number of everlasting hooks. He died in 1128 A.D. at Baghdad.
Ghazali's major contribution lies in religion, philosophy and sufism. A number of Muslim philosophers had been following and developing several viewpoints of Greek philosophy, including the Neoplatonic philosophy, and this was leading to conflict with several Islamic teachings. On the other hand, the movement of sufism was assuming such excessive proportions as to avoid observance of obligatory prayers and duties of Islam. Based on his unquestionable scholarship and personal mystical experience, Ghazali sought to rectify these trends, both in philosophy and sufism.
In philosophy, Ghazali upheld the approach of mathematics and exact sciences as essentially correct. However, he adopted the techniques of Aristotelian logic and the Neoplatonic procedures and employed these very tools to lay bare the flaws and lacunas of the then prevalent Neoplatonic philosophy arid to diminish the negative influences of Aristotelianism and excessive rationalism.
In contrast to some of the Muslim philosophers, e.g., Farabi, he portrayed the inability of reason to comprehend the absolute and the infinite. Reason could not transcend the finite and was limited to the observation of the relative. Also, several Muslim philosophers had held that the universe was finite in space but infinite in time. Ghazali argued that an infinite time was related to an infinite space. With his clarity of thought and force of argument, he was able to create a balance between religion and reason, and identified their respective spheres as being the infinite and the finite, respectively.
In religion, particularly mysticism, he cleansed the approach of sufism of its excesses and reestablished the authority of the orthodox religion. Yet, he stressed the importance of genuine sufism, which he maintained was the path to attain the absolute truth.
He was a prolific writer. His immortal books include Tuhafut al-Falasifa (The Incoherence of the Philosophers), Ihya al-'Ulum al-Islamia (The Rivival of the Religious Sciences), "The Beginning of Guidance and his Autobiography", "Deliverance from Error". Some of his works were translated into European languages in the Middle Ages. He also wrote a summary of astronomy.
Ghazali's influence was deep and everlasting. He is one of the greatest theologians of Islam. His theological doctrines penetrated Europe, influenced Jewish and Christian Scholasticism and several of his arguments seem to have been adopted by St. Thomas Aquinas in order to similarly reestablish the authority of orthodox Christian religion in the West. So forceful was his argument in the favor of religion that he was accused of damaging the cause of philosophy and, in the Muslim Spain, Ibn Rushd (Averros) wrote a rejoinder to his Tuhafut.
AL-IDRISI [Dreses] (1099 -1166 A.D.)
[ Geography (World Map, First Globe) ]
Abu Abdallah Muhammad Ibn Muhammad Ibn Abdallah Ibn Idris al-Qurtubi al-Hasani, was born in Ceuta, Spain, in 1099 A.D. He was educated in Cordova. Later he traveled far and wide in connection with his studies and then flourished at the Norman court in Palermo. The date of his death is controversial, being either 1166 or 1180 A.D.
Biographical notes on him are to be found rather rarely, and according to F. Pons Boigues the underlying reason is the fact that the Arab biographers considered al-Idrisi to be a renegade, since he had been associated with the court of a Christian king and written in praise of him, in his work. The circumstances which led him to settle in Sicily at the court of Roger II are not on record.
His major contribution lies in medicinal plants as presented in his several books, specially[b] Kitab al-Jami-li-Sifat Ashtat al-Nabatat. He studied and reviewed all the literature on the subject of medicinal plants and formed the opinion that very little original material had been added to this branch of knowledge since the early Greek work. He, therefore, collected plants and data not reported earlier and added this to the subject of botany, with special reference to medicinal plants. Thus, a large number of new drugs plants together with their evaluation became available to the medical practitioners. He has given the names of the drugs in six languages : Syriac, Greek, Persian, Hindi, Latin and Berber.
In addition to the above, he made original contributions to geography, especially as related to economics, physical factors and cultural aspects. He made a planishere in silver for King Roger II, and described the world in Al-Kitab al-Rujari (Roger's Book), also entitled Nuzhat al-Mushtaq fi Ikhtiraq al-A faq (The delight of him who desires to journey through the climates). This is practically a geographical encyclopedia of the time, containing information not only on Asia and Africa, but also Western countries.
Al-Idrisi, later on, also compiled another geographical encyclopedia, larger than the former entitled Rawd-Unnas wa-Nuzhat al-afs (Pleasure of men and delight of souls also known as Kitab al-Mamalik wa al Masalik. Apart from botany and geography, Idrisi also wrote on fauna, zoology and therapeutical aspects. His work was soon translated into Latin and, especially, his books on geography remained popular both in the East and the West for several centuries.
IBN AL-BAITAR (DIED 1248 A.D.)
[Pharmacy, Botany]
Abu Muhammad Abdallah Ibn Ahmad Ibn al-Baitar Dhiya al-Din al-Malaqi was one of the greatest scientists of Muslim Spain and was the greatest botanist and pharmacist of the Middle Ages. He was born in the Spanish city of Malaqa (Malaga) towards the end of the l2th century. He learned botany from Abu al-Abbas al-Nabati, a learned botanist, with whom he started collecting plants in and around Spain. In 1219 he left Spain on a plant-collecting expedition and traveled along the northern coast of Africa as far as Asia Minor. The exact modes of his travel (whether by land or sea) are not known, but the major stations he visited include Bugia, Qastantunia ( Constantinople), Tunis, Tripoli, Barqa and Adalia.
After 1224 he entered the service of al-Kamil, the Egyptian Governor, 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, which he either visited or managed to collect plants from stations located there. He died in Damascus in 1248.
Ibn Baitar's major contribution, Kitab al-Jami fi al-Adwiya al-Mu frada, is one of the greatest botanical compilations dealing with medicinal plants in Arabic. It enjoyed a high status among botanists up to the l6th century and is a systematic work that embodies earlier works, with due criticism, and adds a great part of original contribution. The encyclopedia comprises some 1,400 different items, largely medicinal plants and vegetables, of which about 200 plants were not known earlier. The book refers to the work of some 150 authors mostly Arabic, and it also quotes about 20 early Greek scientists. It was translated into Latin and published in 1758.
His second monumental treatise Kitab al-Mughni fi al-Adwiya al-Mu frada is an encyclopedia of medicine. The drugs are listed in accordance with their therapeutical value. Thus, its 20 different chapters deal with the plants bearing significance to diseases of head, ear, eye, etc. On surgical issues he has frequently quoted the famous Muslim surgeon, Abul Qasim Zahravi. Besides Arabic, Baitar, has given Greek and Latin names of the plants, thus facilitating transfer of knowledge.
Ibn Baitar's contributions are characterized by observation, analysis and classification and have exerted a profound influence on Eastern as well as Western botany and medicine. Though the Jami was translated/published late in the western languages as mentioned above, yet many scientists had earlier studied various parts of the book and made several references to it.
ABU ALI HASAN IBN AL-HAITHAM (Alhazen) (965 - 1040 A.D.)
[Physics, Optics, Mathematics ]
Abu Ali Hasan Ibn al-Haitham was one of the most eminent physicists, whose contributions to optics and the scientific methods are outstanding. Known in the West as Alhazen, Ibn aI-Hautham was born in 965 A. D. in Basrah, and was educated in Basrah and Baghdad. Thereafter, he went to Egypt, where he was asked to find ways of controlling the flood of the Nile. Being unsuccessful in this, he feigned madness until the death of Caliph al-Hakim. He also traveled to Spain and, during this period, he had ample time for his scientific pursuits, which included optics, mathematics, physics, medicine and development of scientific methods on each of which he has left several outstanding books.
He made a thorough examination of the passage of light through various media and discovered the laws of refraction. He also carried out the first experiments on the dispersion of light into its constituent colors. His book Kitab-at-Manazir was translated into Latin in the Middle Ages, as also his book dealing with the colors of sunset. He dealt at length with the theory of various physical phenomena like shadows, eclipses, the rainbow, and speculated on the physical nature of light. He is the first to describe accurately the various parts of the eye and give a scientific explanation of the process of vision.
He 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. He contradicted Ptolemy's and Euclid's theory of vision that objects are seen by rays of light emanating from the eyes; according to him the rays originate in the object of vision and not in the eye. Through these extensive researches on optics, he has been considered as the father of modern optics.
The Latin translation of his main work, Kitab-at-Manazir, exerted a great influence upon Western science e.g. on the work of Roger Bacon and Kepler. It brought about a great progress in experimental methods. His research in catoptrics centered on spherical and parabolic mirrors and spherical aberration. He made the important observation that the radio between the angle of incidence and refraction does not remain constant and investigated the magnifying power of a lens. His catoptrics contain 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.
In his book Mizan al-Hikmah Ibn al-Haitham has discussed the density of the atmosphere and developed a relation between it and the height. He also studied atmospheric refraction. He discovered that the twilight only ceases or begins when the sun is 19o below the horizon and attempted to measure the height of the atmosphere on that basis. He has also discussed the theories of attraction between masses, and it seems that he was aware of the magnitude of acceleration due to gravity.
His contribution to mathematics and physics was extensive. In mathematics, he developed analytical geometry by establishing linkage between algebra and geometry. He studied the mechanics of motion of a body and was the first to maintain that a body moves perpetually unless an external force stops it or changes its direction of motion. This would seem equivalent to the first law of motion.
The list of his books runs to 200 or so, very few of which have survived. Even his monumental treatise on optics survived through its Latin translation. During the Middle Ages his books on cosmology were translated into Latin, Hebrew and other languages. He has also written on the subject of evolution a book that deserves serious attention even today.
In his writing, one can see a clear development of the scientific methods as developed and applied by the Muslims and comprising the systematic observation of physical phenomena and their linking together into a scientific theory. This was a major breakthrough in scientific methodology, as distinct from guess and gesture, and placed scientific pursuits on a sound foundation comprising systematic relationship between observation, hypothesis and verification. Ibn al-Haitham's influence on physical sciences in general, and optics in particular, has been held in high esteem and, in fact, it ushered in a new era in optical research, both in theory and practice.
IBN AL-NAFIS [Damishqui] ( 1213 - 1288 A.D.)
Ala-al-Din Abu al-Hasan Ali Ibn Abi al-Hazm al-Qarshi al-Damashqi al-Misri was born in 607 A.H. of Damascus. He was educated at the Medical College-cum-Hospital founded by Nur al-Din Zangi. In medicine his teacher was Muhazzab al-Din Abd al-Rahim. Apart from medicine, Ibn al-Nafis learnt jurisprudence, literature and theology. He thus became a renowned expert on Shafi'i School of Jurisprudence as well as a reputed physician.
After acquiring his expertise in medicine and jurisprudence, he moved to Cairo where he was appointed as the Principal at the famous Nasri Hospital. Here he imparted training to a large number of medical specialists, including Ibn al-Quff al-Masihi, the famous surgeon. He also served at the Mansuriya School at Cairo. When he died in 678 A. H. he donated his house, library and clinic to the Mansuriya Hospital.
His major contribution lies in medicine. His approach comprised writing detailed commentaries on early works, critically evaluating them and adding his own original contribution. His major original contribution of great significance was his discovery of the blood's circulatory system, which was re-discovered by modern science after a lapse of three centuries. He was the first to correctly describe the constitution of the lungs and gave a description of the bronchi and the interaction between the human body's vessels for air and blood. Also, he elaborated the function of the coronary arteries as feeding the cardiac muscle.
The most voluminous of his books is Al-Shamil fi al-Tibb, which was designed to be an encyclopedia comprising 300 volumes, but it could not be completed due to his death. The manuscript is available at Damascus. His book on ophthalmology is largely an original contribution and is also extant. However, his book that became most famous was Mujaz al-Qanun and a number of commentaries were written on this. His own commentaries include one on Hippocrates' book. He wrote several volumes on Ibn Sina's Qanun, that are still extant. Likewise he wrote a commentary on Hunayn Ibn Ishaq's book. Another famous book embodying his original contribution was on the effects of diet on health, entitled Kitab al-Mukhtar fi al-Aghdhiya.
Ibn Al-Nafis' works integrated the then existing medical knowledge and enriched it, thus exerting great influence on the development of medical science, both in the East and the West. However, only one of his books was translated into Latin at early stages and, therefore, a part of his work remained unknown to Europe for a long time.
IBN KHALDUN (1382-1395 A.D.)
Abd al-Rahman Ibn Mohammad is generally known as Ibn Khaldun after a remote ancestor. His parents, originally Yemenite Arabs, had settled in Spain, but after the fall of Seville, had migrated to Tunisia. He was born in Tunisia in 1332 A.D., where he received his early education and where, still in his teens, he entered the service of the Egyptian ruler Sultan Barquq. His thirst for advanced know- ledge and a better academic setting soon made him leave this service and migrate to Fez. This was followed by a long period of unrest marked by contemporary political rivalries affecting his career.
This turbulent period also included a three year refuge in a small village Qalat Ibn Salama in Algeria, which provided him with the opportunity to write Muqaddimah, the first volume of his world history that won him an immortal place among historians, sociologists and philosophers. The uncertainty of his career still continued, with Egypt becoming his final abode where he spent his last 24 years. Here he lived a life of fame and respect, marked by his appointment as the Chief Malakite Judge and lecturing at the AL-Azhar University, but envy caused his removal from his high judicial office as many as five times.
Ibn Khaldun's chief contribution lies in philosophy of history and sociology. He sought to write a world history preambled by a first volume aimed at an analysis of historical events. This volume, commonly known as Muqaddimah or 'Prolegomena', was based on Ibn Khaldun's unique approach and original contribution and became a masterpiece in literature on philosophy of history and sociology. The chief concern of this monumental work was to identify psychological, economic, environmental and social facts that contribute to the advancement of human civilization and the currents of history.
In this context, he analyzed the dynamics of group relationships and showed how group-feelings, al-'Asabiyya, give rise to the ascent of a new civilization and political power and how, later on, its diffusion into a more general civilization invites the advent of a still new 'Asabiyya in its pristine form. He identified an almost rhythmic repetition of rise and fall in human civilization, and analyzed factors contributing to it. His contribution to history is marked by the fact that, unlike most earlier writers interpreting history largely in a political context, he emphasized environmental, sociological, psychological and economic factors governing the apparent events. This revolutionized the science of history and also laid the foundation of Umraniyat (Sociology).
Apart from the Muqaddimah that became an important independent book even during the lifetime of the author, the other volumes of his world history Kitab al-I'bar deal with the history of Arabs, contemporary Muslim rulers, contemporary European rulers, ancient history of Arabs, Jews, Greeks, Romans, Persians, etc., Islamic History, Egyptian history and North-African history, especially that of Berbers and tribes living in the adjoining areas. The last volume deals largely with the events of his own life and is known as Al-Tasrif. This was also written in a scientific manner and initiated a new analytical tradition in the art of writing autobiography A book on mathematics written by him is not extant.
Ibn Khaldun's influence on the subject of history, philosophy of history, sociology, political science and education has remained paramount ever since his life. His books have been translated into many languages, both in the East and the West, and have inspired subsequent development of these sciences. For instance, Prof. Gum Ploughs and Kolosio consider Muqaddimah as superior in scholarship to Machiavelli's[b] The Prince written a century later, as the former bases the diagnosis more on cultural, sociological, economic and psychological factors.
Source: Ummah