Adelard of Bath (Latin: Adelardus Bathensis) (1116? - 1142?) was a twelfth century English scholar, best known for translating many important Arabic scientific works of astrology, astronomy, philosophy and mathematics into Latin, and introducing ancient Greek texts which had only existed in Arabic form to Europe. During a period of seven years he traveled throughout North Africa and Asia Minor, and acquired a knowledge of Arabic and exposure to Arabic translations of ancient Greek texts. His most influential work was his translation, from Arabic into Latin, of Euclid's Elements, which became a standard textbook of geometry in Europe for the next eight centuries. He also translated al-Khwarizmi's tables (Kharismian Tables), which became the first Latin astronomical tables of the Arabic type, with their Greek influences and Indian symbols. Adelard also introduced the Arabic notation for numbers and zero.
Adelard was a pioneer of the scientific renaissance of the twelfth century, one of the first to call for observation,experimentation, and innovation rather than blind acceptance of authority on scientific questions. His work De Eodem et Diverso (On Identity and Difference) defended philosophy against the pursuit of worldly interests, and contains an early discussion of universals.
The only historical records of Adelard of Bath outside of his own works come from the city of Bath, in England. He held lands in Wiltshire, and in 1106 a certain ‘Athelard, son of Fastrad,’ witnessed a charter drawn up at the Abbey of Bath. Other documents from around this date mention ‘Athelardus’ as the steward in the Bishop of Bath’s household, and his name is listed in charters of 1130 and 1135, and 1139. From anecdotes in his literary writings we know that Adelard studied in Tours in the Loire Valley in west central France, took his (English) students to Laon in the Picardie region of northern France, and met the Queen of France. After leaving Laon, Adelard traveled for about seven years first visiting first Salerno, southeast of Naples, where there was a famous medical school. From Salerno Adelard traveled to Sicily, which at that time was under Norman control but still strongly influenced by its Arabic past. He then visited Cilicia (an ancient district of southern Anatolia, in modern Turkey) on the northeast coast of the Mediterranean, and followed the coast of the Mediterranean east to Syria and Palestine. By 1130 he was back in Bath, England.
Adelard became an expert in the Arabic language, which he might have learned in Spain or in Sicily, and came into contact with Spanish-Arabic texts which could have been brought from Spain to Sicily by several scholars who had lived in Spain. Adelard translated some of these works into Latin, and was instrumental in introducing Arabic knowledge and the Arabic tradition of rational scientific inquiry to Europe. His latest work, a text on cosmology, was addressed to the young prince who later became Henry II, and may date to 1149.
Adelard was one of the first medieval scholars to seek knowledge by traveling in Greece and Asia Minor, and to utilize the knowledge of the Arabians in discussions of mathematics and natural science. He was the author of a number of works in Latin, including translations of Arabic works on arithmetic, astronomy, astrology and talismans on which he may have cooperated with a scholar of Arabic; and several original literary and philosophical works including texts on the study of liberal arts, falconry, natural science, cosmology and the use of the abacus. Three of his original works, on natural science and falconry, are addressed to a nephew who took an active part in the dialog.
His first known work, a text on philosophy, was written before 1116 and dedicated to William, Bishop of Syracuse. Syracuse was one of the most important cities of ancient Sicily; this work was probably written around the time of Adelard's visit to Sicily, but its Platonic tone indicates that Adelard had not yet been influenced by the learning of the Arabs. His most influential work was his translation