Liber Abbaci

Abstract

This chapter discusses the role played by Leonardo Fibonacci's Liber abbaci in introducing modern arithmetic to the West. In the prologue of Liber abbaci, Fibonacci says he learned the nine Indian numbers used in trade when traveling with his father, meeting merchants in Egypt, Syria, Greece, and Provence. He implies that the Indian numbers were new to the merchants and wrote that the “Latin race” was lacking knowledge of the Indian method of arithmetic. The question of who introduced and influenced the practice of reckoning with Indian numerals to Europe has no simple answer, but there is no doubt that it took place from the late tenth century onward. By the end of the eleventh century, news of the Indian number system was all over Europe in the form of counters of the Gerbertian abacus marked with Indian numerals.