Introduction

Abstract

Mukhammad ibn Musa abu Djafar al-Khorezmi was born about 780 in the area south of Lake Aral known today as Uzbekistan and died about 850. He lived in Bagdad in the “House of Wisdom” of the caliph al-Mamun, at the time when the principal works of Greek mathematicians were being translated into Arabic. His work “Kitab hisab al-’adad al-hindi”, in Latin called “algorithmi de numero indorum”, shows Indian influence in the terms used and in the tendency to formulate in an algebraic way. Later it was shortly named liber algorithmi. The dispute which arose in the 15th century between the algorists who calculated by means of figures (whose technical skill originated from the algorismus-writings of the scholastics, from translations and revisions from the Arabic) and the abacists who taught calculating “on the lines” originating from the Roman Abacus (whose influence persisted into the 17th century, and in Russia up to the present day) is shown on contemporary wood carvings (Fig. 0.1).