Leonardo Fibonacci
Leonardo Fibonacci was an Italian mathematician best known for a sequence of numbers that bear his name. This sequence of numbers, called the Fibonacci sequence, is made up of the sum of the preceding two numbers, beginning with 0 and 1. For example, the next number in the sequence is 1, followed by 2 (1 + 1), then 3 (2 + 1), 5 (3 + 2), 8 (5 + 3), 13 (8 + 5), 21 (13 + 8), and so on.
Fibonacci is also known for a system of numeration in which the numbers are expressed by symbols. This system is still in use today in many countries. He is also known for his study of mathematics, which he wrote about in his books Liber Abaci and Practica geometriae.
Fibonacci was born in Pisa, Italy in 1170. His father Guilielmo was a banker and a merchant who traveled from city to city dealing in business. Leonardo had a good education and was exposed to Number Theory, the basis of modern mathematics, while he was still a boy. He received a thorough instruction in the seven liberal arts and three mathematical sciences.
At the age of twenty-three, Fibonacci traveled to Egypt and Syria, then part of the Islamic world. During his stays in Egypt he studied the Hindu-Arabic system of numeration, which is based on the position of each numeral to indicate its magnitude. He also encountered a variety of problems dealing with arithmetic, geometry and algebra.
When Leonardo returned to Italy in 1200, he wrote the Liber Abaci, in which he introduced European readers to the Hindu-Arabic numeral system. He also wrote Practica geometriae, which was a compilation of the problems he encountered in Egypt and dealt with numeration points, fractions, epicycloids and geometric series.
Fibonaccis work had an enormous impact on the development of mathematics in Europe. He was one of the first to introduce the Hindu-Arabic numeral system in Europe and as such is often credited with making mathematics more accessible to his contemporaries. The Fibonacci sequence and his numeration system are still in use today, although with more sophistication than in the 13th century.
Fibonacci died in Pisa in 1240 and although his life is not well known, he has left an enduring legacy with his contributions to mathematics and business calculations. His work is still studied by modern mathematicians and historians and deservedly so, as he was an icon of the Middle Ages who opened the door to modern mathematics.
