Fibonacci was a celebrated medieval Italian mathematician. He is deemed the most brilliant Western mathematician during the medieval times. Fibonacci is short for ‘figlio di Bonacci’ which means son of Bonacci and was also referred to as Leonardo Bonacci. He is accredited for introducing Western world to Hindu-Arabic Numeral system. In 1202 he composed a book employing that numeral system, Liber Abaci (Book of Calculations). His most popular work so far is the introduction of Fibonacci numbers into European mathematics.
It is reported that Fibonacci was born around 1175 in Pisa. His father, Guglielmo Bonacci, was an affluent Italian merchant who was also believed to be a consul for Pisa. Bonacci directed a trading post in several states including one in North Africa and Bugia. As a child, he travelled along with his father and amid his stay in Bugia he came across Hindu-Arabic numerals. He made acquaintance with a number of merchants during his trip through the Mediterranean coast, he learned their calculation methods. He was once a guest of an emperor who was inclined toward mathematics and science, Emperor Frederick II.
There is not much known about Fibonacci’s personal life but it is established that his extensive travels made him realize the significance of the Hindu-Arabic system. Hence, he began writing a book on calculation system using that numeral system that resulted in the popularity of Hindu-Arabic numeral usage in the West. The Republic of Pisa in 1240 granted Fibonacci a salary in a decree that was their way of honoring his services to the city as an advisor of accounting and other such important matters.
His magnum opus Liber Abaci brought the so-called modus Indorum to light. The digits 0–9 and place value were presented in the book and its practical use and value had been highlighted. It suggested the use of Arabic numerals for commercial purposes, for instance, bookkeeping, measurement and conversion of weight, money changing, tallying numbers and calculation of interest among other practical implications. The book garnered much praise throughout Europe leaving a positive impact on the mathematical endeavors of that region.
In the first section of the book Fibonacci compared the Arabic numerals with other systems including Roman system, abacus calculation system, ancient Egyptian multiplication method etc. Drawing those parallels between different systems, he discovered Arabic numeral system would prove to be beneficial in terms of business calculation. He found it easier for commercial accounting, therefore the banking and accounting in Europe grew by leaps and bounds. The following section of the book highlights the uses of Arabic numerals in business. Conversion of different currencies, calculation of profit and interest are illustrative of that. Furthermore, the book offers an exposition of prime numbers and irrational numbers.
The most celebrated of Fibonacci’s work is Fibonacci’s number sequence which was also discussed in his book but was not referred as that. The idea was influenced by Indian mathematicians during sixth century. The sequence numbers entail that each number is the sum of previous two. Instead of following the 0-2 sequence he used 1-2.
The correct year of his death is disputed as some believe it was 1240 while others assume it was a decade later. Fibonacci’s timeless work was also honored posthumously, when a statue of Fibonacci was constructed and placed in his birthplace Pisa, in the 19th century. Now the statue can be located in the western gallery of the Camposanto.