Leonardo of Pisa (aka Fibonacci)
Have you ever wondered where we got our decimal numbering system from? The Roman Empire left Europe with the Roman numeral system. This system was not ideal for more complex mathematical calculations. It was unwieldy and difficult to use.
However the Roman numerals were not displaced until the 13th Century AD when Fibonacci published his Liber abaci, “The Book of Calculations”.
Fibonacci, or more correctly Leonardo da Pisa, was born in Pisa in 1175 AD. He was the son of a Pisan merchant who also served as a customs officer in North Africa. He travelled widely in Barbary (Algeria) and was later sent on business trips to Egypt, Syria, Greece, Sicily and Provence.
In 1200 he returned to Pisa and used the knowledge he had gained on his travels to write Liber abaci in which he introduced the Latin-speaking world to the decimal number system. The first chapter of Part 1 begins:
These are the nine figures of the Indians: 9 8 7 6 5 4 3 2 1. With these nine figures, and with this sign 0 which in Arabic is called zephirum, any number can be written, as will be demonstrated.
The Fibonacci Sequence
Fibonacci is perhaps best known for a simple series of numbers, introduced in Liber abaci and later named the Fibonacci numbers in his honour.
The series begins with 0 and 1. After that, use the simple rule:
Add the last two numbers to get the next.
1, 2, 3, 5, 8, 13, 21, 34, 55, 89, 144, 233, 377, 610, 987,…