Texas A&M University – Central Texas
Dr. Mary Kelly
Northern Italy in the early thirteen century was a land subdivided into multiple feuding city-states. Among the many remnants of defunct Roman Empire was a numerical system (I, ii, iii, iv…) singularly ill suited to complex mathematical calculation, let alone the needs of commerce. Nowhere was this more of a problem than in Pisa, where merchants also had to contend with seven different forms of coinage in circulation. By comparison, economical life in the Eastern world was far more advanced, just as it had been in the time of Charlemagne. To discover modern finance, Europe needed to import it. In this, a young mathematician called Leonardo of Pisa, or Fibonacci played a crucial role. Leonardo Fibonacci also known as Leonardo Pisano, Leonardo of Pisa, was the greatest European mathematician of the middle ages. He was born in Pisa in Italy circa 1170 and died sometime after 1240. Leonardo’s father, Gugliemo, was a customs official and engaged in commerce representing Pisa at Bougie on the north coast of Africa. Young Leonardo consequently received a Moorish education as well as the traditional European education and was introduced to Hindu-Arabic numbers. Later on, he traveled about the Mediterranean visiting Egypt, Syria, Greece, Sicily and Provence, meeting with scholars and becoming acquainted with the various arithmetical systems used by the merchants. In his book, the Liber abaci, which fills 459 printed pages, he explained the most perfect methods of calculating with whole numbers and with fractions, practice, extraction of the square and cube roots, proportion, chain rule, finding of proportional parts, averages, progressions, even compound interest, just as in the completest mercantile arithmetic of later days. They teach further the solution of problems leading to equations of the first and second...