Adelard of Bath
Adelard of Bath (; 1080 1152 AD) was a 12th-century English natural philosopher. He is known both for his original works and for translating many important Arabic and Greek scientific works of astrology, astronomy, philosophy and mathematics into Latin from Arabic versions, which were then introduced to Western Europe. He is known as one of the first to introduce the Arabic numeral system to Europe. He stands at the convergence of three intellectual schools: the traditional learning of French schools, the Greek culture of Southern Italy, and the Arabic science of the East.
History of mathematical notation
Abū al-Hasan ibn Alī al-Qalasādī (1412–1482) was the last major medieval Arab algebraist, who improved on the algebraic notation earlier used by Ibn al-Yāsamīn in the 12th century and, in the Maghreb, by Ibn al-Banna in the 13th century. In contrast to the syncopated notations of their predecessors, Diophantus and Brahmagupta, which lacked symbols for mathematical operations, al-Qalasadi's algebraic notation was the first to have symbols for these functions and was thus "the first steps toward the introduction of algebraic symbolism." He represented mathematical symbols using characters from the Arabic alphabet.The 14th century saw the development of new mathematical concepts to investigate a wide range of problems. The two widely used arithmetic symbols are addition and subtraction, + and −. The plus sign was used by 1360 by Nicole Oresme in his work "Algorismus proportionum". It is thought an abbreviation for "et", meaning "and" in Latin, in much the same way the ampersand sign also began as "et". Oresme at the University of Paris and the Italian Giovanni di Casali independently provided graphical demonstrations of the distance covered by a body undergoing uniformly accelerated motion, asserting that the area under the line depicting the constant acceleration and represented the total distance traveled. The minus sign was used in 1489 by Johannes Widmann in "Mercantile Arithmetic" or "Behende und hüpsche Rechenung auff allen Kauffmanschafft,". Widmann used the minus symbol with the plus symbol, to indicate deficit and surplus, respectively. In "Summa de arithmetica, geometria, proportioni e proportionalità", Luca Pacioli used symbols for plus and minus symbols and contained algebra.