Who was Fibonacci and what is his true legacy?

So much is said about this Fibonacci guy. The number sequence of his name is reverred and idolised.

But who was he?

His full name was **Leonardo Pisano**, born in Pisa, Italy in the late 1100s.

‘Fibonacci’ became associated as his infamous name because on the first page of his Liber Abaci manuscript book which was released in 1202, he stated himself as Leonardo ‘filius Bonacci’ meaning ‘son of Bonacci’ and so became compressed to fi-Bonacci.

In popular culture he is of course known for the Fibonacci number sequence fame. But on closer study that isn’t really his biggest achievement. The true legacy we owe to him is the introduction of the numbers numerals 0-9, the decimal numbers we use today.

## Fibonacci’s true legacy and Roman Numerals

Europe in the 1100’s, Roman Numerals were used. (Can you imagine doing the fibonacci sequence in roman numerals?!)

Fibonacci was currently writing a book ‘Liber Abaci’ that was to introduce the** hindu-arabic number system** to northern Europe. This was a base 10 number system (there were other base number systems too) but it is the base 10 that Fibonacci popularised in the 1200’s through his book and are the numbers we use today.

## This is Fibonacci’s true legacy.

He brought this number system to Europe and it changed the lives of merchant traders in the Mediterranean at the time. This number system (the same one we all learn in primary school) is based on digits that represent place value and importantly gives a place value to zero.

## Who was Fibonacci?

His father worked with the merchant traders and through this connection gave his son a start in the accounting world.

Fibonacci was lucky, he got an education. I imagine not every child did then. What he learnt was accounting. Back then being an accountant was useful, Italy was the centre of the mediterranean trade routes and not everyone could do the arithmetic needed for trading, so you sourced an accountant to do it for you.

The abacus was their tool. Calculating trading amounts on these neat handheld devices (sound familiar?) Everything then written in Roman numerals because that was how Europe scribed numbers at the time. I imagine it was quite a laborious process.

But our young Fibonacci loved it. We can assume he was pretty good at it. Maths was a rigorous discipline and one that was mostly explained with words and phrases and Roman numerals. The equations and digits we know today weren’t yet in use. We can imagine him scribing numerals on parchment paper like writing religious papers.

His father was one of these merchant traders and clearly someone of importance in Italy , important enough to be able to secure the coveted accounting education for his son.

## What is Fibonacci’s true legacy?

So the introduction of this number system through his book Liber Abaci brought these numbers to the west. It happened slowly, remember there wasn’t a printing press yet so any copies needed to be written by hand. His book was a log of all the computations one could do with these numbers. Explaining all the procedures in long word form.

The inclusion of a sequence of numbers that he explained with the example of the Rabbit Riddle was a mere side note in this great work. As I understand it, at the time it didn’t get much attention. If you think about it, it was to demonstrate the ability of these numbers , what they could do. They had an economic quality about them as oppose to Roman numerals that quickly needed more and more letters as the number grew only slightly larger.

For about 25 years after he wrote the book in 1202 , Fibonacci remained the go-to man in Italy for pure mathematics. He penned other books on geometry and number theory, yet some of his works have not survived.

Fibonacci’s fame reached the court of the Roman Emperor. There he demonstrated his skill in using square roots of fractions combined with other base number systems to solve problems that were only being worked on in the Far Eastern territories. At that time they were ahead of western mathematical knowledge. Fibonacci was truly ahead of his time.

After 1240 nothing is known of what happened to Fibonacci, how long he lived or where he died is not known. There are only a two or three places in Pisa and Florence where his name is used in memorial tribute.

Yet the Hindu numbers he brought to Europe eventually took hold, replacing the resistance they had initially received. By the 15th Century (that’s at least 200 years later) they finally overtook the abacus and were to appear on coins and calendars.

The use and popularity of these numbers spread with the advent of the printing press (as many things did!) and the European mathematicians of the renaissance years thanked the ease with which these numerals lent themselves to algebra. Meaning that pure mathematics (Fibonacci’s passion) only took off 300 years after he lived, leaving his monumental contributions to mathematics overlooked during his lifetime.

## Fibonacci legacy in modern times

These modern numerals were put together as a sequence in 1202 by Fibonacci in his book Liber Abaci.

Yet it wasn’t until the mid 1800’s that a French Mathematician Edouard Lucas who studied the number sequence gave them the name **“The Fibonacci Sequence”.** That is a full 700 years after the Fibonacci numbers and the Rabbit Riddle were introduced.

And so the genius legend of the man from the 1100’s came into his own. Thank you Fibonacci!

But can you see how it is only in our modern era (from 1800’s) that we have called it the Fibonacci sequence?.

## Have we overlooked what the Fibonacci sequence actually is?

It seems to have become reverred almost to a place where we no longer appreciate that it is an expression of the divine proportion. In today’s world, numbers are held in such high esteem that we feel these numbers have supernatural powers and that they even control nature!

But it was the divine proportion that came first and these numbers are an EXPRESSION of that. Just as natural forms express this divine proportional relationship. Fibonacci the man, was ahead of his time and he felt the connection between what mystics had been searching for and these new numerals he could play maths games with.

I wonder, do we hold numbers in too high regard? and that actually its the demonstration of this relational experience they have to each other that we can learn most from.