Al-Biruni
Abu Rayhan Muhammad ibn Ahmad al-Biruni, known as al-Biruni was a Khwarazmian Iranic scholar and polymath during the Islamic Golden Age. He has been called variously "Father of Comparative Religion", "Father of modern geodesy", Founder of Indology and the first anthropologist.
Al-Biruni was well versed in physics, mathematics, astronomy, and natural sciences; he also distinguished himself as a historian, chronologist, and linguist. He studied almost all the sciences of his day and was rewarded abundantly for his tireless research in many fields of knowledge. Royalty and other powerful elements in society funded al-Biruni's research and sought him out with specific projects in mind. Influential in his own right, al-Biruni was himself influenced by the scholars of other nations, such as the Greeks, from whom he took inspiration when he turned to the study of philosophy. A gifted linguist, he was conversant in Khwarezmian, Persian, Arabic, and Sanskrit, and also knew Greek, Hebrew, and Syriac. He spent much of his life in Ghazni, then capital of the Ghaznavids, in modern-day central-eastern Afghanistan. In 1017, he travelled to the Indian subcontinent and wrote a treatise on Indian culture entitled , after exploring the Hindu faith practiced in India. He was, for his time, an admirably impartial writer on the customs and creeds of various nations, his scholarly objectivity earning him the title in recognition of his remarkable description of early 11th-century India.
Name
Al-Biruni's name is derived from the Persian word or , as he was born in an outlying district of Kath, the capital of the Afrighid kingdom of Khwarazm. The city, now called Beruniy, is part of the autonomous republic of Karakalpakstan in northwest Uzbekistan.His name was most commonly latinized as Alberonius.
Life
Al-Biruni spent the first twenty-five years of his life in Khwarezm where he studied Islamic jurisprudence, theology, grammar, mathematics, astronomy, medicine and philosophy and dabbled not only in the field of physics, but also in those of most of the other sciences. The Iranian Khwarezmian language, which was Biruni's mother tongue, survived for several centuries after Islam until the Turkification of the region – at least some of the culture of ancient Khwarezm endured – for it is hard to imagine that the commanding figure of Biruni, a repository of so much knowledge, should have appeared in a cultural vacuum. He was sympathetic to the Afrighids, who were overthrown by the rival dynasty of Ma'munids in 995. He left his homeland for Bukhara, then under the Samanid ruler Mansur II the son of Nuh II. He corresponded with Avicenna, and there are extant exchanges of views between these two scholars.In 998, he went to the court of the Ziyarid amir of Tabaristan, Qabus. There he wrote his first important work, on historical and scientific chronology, probably around 1000, though he later made some amendments to the book. He also visited the court of the Bavandid ruler Al-Marzuban. Accepting the definite demise of the Afrighids at the hands of the Ma'munids, he made peace with the latter who then ruled Khwarezm. Their court at Gorganj was gaining fame for its gathering of brilliant scientists.
In 1017, Mahmud of Ghazni captured Rey. Most scholars, including al-Biruni, were taken to Ghazni, the capital of the Ghaznavid dynasty. Biruni was made court astrologer and accompanied Mahmud on his invasions into India, living there for a few years. He was 44 when he went on the journeys with Mahmud of Ghazni. Biruni became acquainted with all things related to India. During this time he wrote his study of India, finishing it around 1030. Along with his writing, Al-Biruni also made sure to extend his study to sciences while on the expeditions. He sought to find a method to measure the height of the sun, and created a makeshift quadrant for that purpose. Al-Biruni was able to make much progress in his study over the frequent travels that he went on throughout the lands of India.
Astronomy
Of the 146 books written by al-Bīrūnī, 95 are devoted to astronomy, mathematics, and related subjects like mathematical geography. He lived during the Islamic Golden Age, when the Abbasid Caliphs promoted astronomical research, because such research possessed not only a scientific but also a religious dimension: in Islam worship and prayer require a knowledge of the precise directions of sacred locations, which can be determined accurately only through the use of astronomical data.In carrying out his research, al-Biruni used a variety of different techniques dependent upon the particular field of study involved.
His major work on astrology is primarily an astronomical and mathematical text; he states: "I have begun with Geometry and proceeded to Arithmetic and the Science of Numbers, then to the structure of the Universe and finally to Judicial Astrology, for no one who is worthy of the style and title of Astrologer who is not thoroughly conversant with these for sciences." In these earlier chapters he lays the foundations for the final chapter, on astrological prognostication, which he criticises. In a later work, he wrote a refutation of astrology, in contradistinction to the legitimate science of astronomy, for which he expresses wholehearted support. Some suggest that his reasons for refuting astrology relate to the methods used by astrologers being based upon pseudoscience rather than empiricism and also to a conflict between the views of the astrologers and those of the orthodox theologians of Sunni Islam.
He wrote an extensive commentary on Indian astronomy in the — mostly translation of Aryabhatta's work, in which he claims to have resolved the matter of Earth's rotation in a work on astronomy that is no longer extant, his :
he rotation of the earth does in no way impair the value of astronomy, as all appearances of an astronomic character can quite as well be explained according to this theory as to the other. There are, however, other reasons which make it impossible. This question is most difficult to solve. The most prominent of both modern and ancient astronomers have deeply studied the question of the moving of the earth, and tried to refute it. We, too, have composed a book on the subject called Miftah-ilm-alhai'a , in which we think we have surpassed our predecessors, if not in the words, at all events in the matter.
In his major astronomical work, the Mas'ud Canon, Biruni observed that, contrary to Ptolemy, the Sun's apogee was mobile, not fixed. He wrote a treatise on the astrolabe, describing how to use it to tell the time and as a quadrant for surveying. One particular diagram of an eight-geared device could be considered an ancestor of later Muslim astrolabes and clocks. More recently, Biruni's eclipse data was used by Dunthorne in 1749 to help determine the acceleration of the Moon, and his data on equinox times and eclipses was used as part of a study of Earth's past rotation.
Refutation of Eternal Universe
Like later adherents of the Ash'ari school, such as al-Ghazali, al-Biruni is famous for vehemently defending the majority Sunni position that the universe had a beginning, being a strong supporter of creatio ex nihilo, specifically refuting the philosopher Ibn Sina in a multiple letter correspondence. Al-Biruni stated:He further stated that Aristotle, whose arguments Avicenna uses, contradicted himself when he stated that the universe and matter has a start whilst holding on to the idea that matter is pre-eternal. In his letters to Avicenna, he stated the argument of Aristotle, that there is a change in the creator. He further argued that stating there is a change in the creator would mean there is a change in the effect and that the universe coming into being after not being is such a change. Al-Biruni was proud of the fact that he followed the textual evidence of the religion without being influenced by Greek philosophers such as Aristotle.
Physics
Al-Biruni contributed to the introduction of the scientific method to medieval mechanics. He developed experimental methods to determine density, using a particular type of hydrostatic balance. Al-Biruni's method of using the hydrostatic balance was precise, and he was able to measure the density of many different substances, including precious metals, gems, and even air. He also used an experimental method to determine the radius of the earth, which he did by measuring the angle of elevation of the horizon from the top of a mountain and comparing it to the angle of elevation of the horizon from a nearby plain.In addition to developing the hydrostatic balance, Al-Biruni also wrote extensively on the topic of density, including the different types of densities and how they are measured. His work on the subject was very influential.
Geography and geodesy
Bīrūnī devised a novel method of determining the Earth's radius by means of the observation of the height of a mountain. He carried it out at Nandana in Pind Dadan Khan. He used trigonometry to calculate the radius of the Earth using measurements of the height of a hill and measurement of the dip in the horizon from the top of that hill. Sparavigna writes that his calculated radius for the Earth of 3928.77 miles was 2% higher than the actual mean radius of 3847.80 miles. His estimate was given as 12,803,337 cubits, so the accuracy of his estimate compared to the modern value depends on what conversion is used for cubits. The exact length of a cubit is not clear; with an 18-inch cubit his estimate would be 3,600 miles, whereas with a 22-inch cubit his estimate would be 4,200 miles. One significant problem with this approach is that Al-Biruni was not aware of atmospheric refraction and made no allowance for it. He used a dip angle of 34 arc minutes in his calculations, but refraction can typically alter the measured dip angle by about 1/6, making his calculation only accurate to within about 20% of the true value.In his Codex Masudicus, Al-Biruni theorized the existence of a landmass along the vast ocean between Asia and Europe, or what is today known as the Americas. He argued for its existence on the basis of his accurate estimations of the Earth's circumference and Afro-Eurasia's size, which he found spanned only two-fifths of the Earth's circumference, reasoning that the geological processes that gave rise to Eurasia must surely have given rise to lands in the vast ocean between Asia and Europe. He also theorized that at least some of the unknown landmass would lie within the known latitudes which humans could inhabit, and therefore would be inhabited.