Fibonacci is a beautifully written novel that imagines the life of an incredibly influential yet forgotten figure. Because so little is known about Leonardo "Fibonacci" Bonacci, the author deserves tremendous credit for writing a believable, deeply human portrait of the man who introduced the Hindu-Arabic numeral system to the Western world. The author created Bonacci to be relentlessly curious, constantly searching for meaning in patterns, abhorring black/white thought, and questioning all of reality as he perceives it- all of which seem to paint a pretty realistic picture of how someone with Fibonacci's innate mathematical genius would probably have thought and behaved.

The book follows Fibonacci from his home in Pisa to Algeria, Syria, and Egypt, where he encounters the numeral system we now take completely for granted. Prior to Fibonacci, Western merchants relied on Roman numerals, finger counting, and the abacus to conduct trade, making trade and business incredibly cumbersome and time-consuming. He faces new, revolutionary ideas (like the concept of zero!) and meets them with resistance, but still makes his way home to Pisa, changing business, commerce, and likely the world as we know it.

I also really liked how the author incorporated the origins of the Fibonacci Sequence where it fit into the book. The Fibonacci Sequence is an enigmatic mathematical pattern that appears throughout nature and continues to hold extreme influence in fields ranging from science to finance and even spiritualism. As a day trader who uses Fibonacci retracements and extensions every day, I loved reading how Fibonacci himself would have probably observed the sequences in nature, architecture, and quite possibly even in his own behavior.

Ultimately this book is a very fitting tribute to Leonardo Bonacci, and a reminder that some of history's greatest innovators are also completely forgotten or overlooked.

Thank you to NetGalley, Wandering Steps Media and the author for the advance copy of this book.

An unconventional and mysterious window into one of the most influential minds in human history. The narrative resists easy answers, pulling you deeper into its puzzle with every page. It lingers long after the final chapter, begging to be meditated over in the reader's mind for weeks afterwards.

This story trusts the reader to sit with ambiguity rather than spelling everything out, which I am sure will challenge some audiences (in a positive manner). Anyone drawn to stories that reward patience and reflection will find themselves richly rewarded. It is the rare book that feels less like something you finish and more like something you carry with you.

“Liber Abaci is one of the most important books on mathematics of the Middle Ages. Its effect was enormous in disseminating the Hindu number system and the methods of algebra throughout Europe…Liber Abaci, or the Book of Calculation, appeared first in 1202…and in a second version in 1228…It was Leonardo’s purpose to replace Roman numerals with the Hindu numerals not only among scientists, but in commerce and among the common people”."The ten numerals of the Hindu number system are presented, including zero, that is called zephir from the Arabic…numbers of any size can be represented with only the ten numerals.”

-Introduction of Fibonacci’s Liber Abaci
Leonardo Pisano’s Book of Calculation
[translated by Laurence Sigler]

“While based on fragments of truth, this novel is fiction…recreated through reading, research, and the error of imagination”

-Tom Harrits, author

Leonardo, the elder son of the Bonacci family was born in Pisa, Italy in 1170. At that time in history, the Pisans had established key shipping ports through the Arno River, securing “direct lifelines into the flow of goods and money from East to West [and back]; shipping lanes, The Silk Road, the intertwining of every tribe and tongue, the wealth of the world.” Guilielmo, Leo's father, was a giant among men, a jovial wordsmith who was instrumental in expanding the “great game of trade and profit” in Pisa. Leo was expected to inherit Guilielmo’s booming business and to this end, he had been instructed in reading, writing and arithmetic. Guilielmo’s fondaco was a trading post where men came to barter and trade, often haggling over prices. Even as the sea receded over time and Pisa became landlocked, Guilielmo’s profit margin had not diminished.

How could goods and services be quantified, priced and converted from one foreign currency to another? Finger counting was used to add and subtract while an abacus was always available. Calculations were prone to error especially when computing large monetary sums.

Advancement opportunities were offered to Guilielmo, a diplomatic post to represent the merchants of Pisa in the Mediterranean port of Bugia, in northeastern Algeria. Risk would be involved in dealing with people from an unfamiliar culture. Leaving for his new post, Guilielmo encouraged Leo to consider joining him in one year's time. Thirteen year old Leo was determined to “glean every last gem of insight from the greatest minds of his trade.”

The novel then morphs into Leo’s coming of age phase with all the indecision a teenager might experience…should he stay at home with his mother and younger brother or travel to his father by sailing vessel with an escort, a trip that included entry into the waters of the Barbary Coast. Friendship had already been a challenge in Pisa. With a lack of certainty and a heavy heart, Leo left his family behind to join his father in Bugia. This life changing decision would place him on a path to puzzle out and embrace a new method of calculation.
Guilielmo was determined to hire a tutor to teach Leo Arabic. Ever curious, Leo wandered down the weaving interconnected streets of the Arab quarter stopping at the window of an Arab customhouse. No finger counting…no abacus…computations were done differently…symbols written out neatly in grids. The customhouse owner eventually agreed to teach Leo the numerology used. “With the nine numbers, carved upon a tablet, any number could be written, any number calculated…one last symbol…untouched by any explanation…a funny, round little symbol, the zephir [the zero]...take it out and none of it seemed to work. Let it fill the spaces between, however, and suddenly it all came to life.” A puzzle…a method to replace the antiquated finger counting in Pisa. Could he convince others of the merits of this computational technique?

The Fibonacci Sequence began with the puzzle of rabbits as per the Liber Abaci.
“A certain man put a pair of rabbits in a place surrounded on all sides by a wall. How many pairs of rabbits can be produced from that pair in a year if it is supposed that every month each pair begets a new pair which from the second month on becomes productive?”
The resulting sequence is 0,1,1,2,3,5,8,13,21,34,55… Each number is the sum of the two preceding numbers. Fibonacci numbers help us see the order, beauty and wonder of our world; the pattern of seeds in flowering plants, the spirals on snail shells.

Fibonacci by Tom Harrits is a wonderful debut novel. Harrits captured the uncertainty, the angst, and the distractibility of Leo’s teenage years. In view of the times in Bugia where the government was often in flux and mistrust was rampant, Leo refused to heed his father’s warnings about personal safety and ventured out to pursue the knowledge imparted by a kind, albeit suspicious customhouse owner, an association that would change business dealings and commerce in early Pisa.

Highly recommended.
Thank you Wandering Steps Media and Net Galley for the ARC in exchange for an honest review.