**The knowledge of all sums… **

**😀 😀 😀 🙂**

A few years ago, Keith Devlin published *The Man of Numbers: Fibonacci’s Arithmetic Revolution*, which combined a biography of the famous mathematician with an explanation of what his fame rests on. This book is the story of researching and writing that book, also telling the little that is known about Fibonacci’s life and describing his arithmetical legacy.

It’s a strange little book. It reminded me of being left with bits of leftover wool after knitting an elaborate sweater and deciding to use them to make a matching scarf. It feels like an amalgam of all the things Devlin would have liked to have included in his first book, but didn’t think quite fitted. Knowing nothing whatsoever about Fibonacci, I found it reasonably interesting since it gave me the basics about his achievements, but I’m not sure of how much interest it would hold for anyone who already knows about him, or indeed, who has read Devlin’s earlier book. Devlin starts with an introduction in which he describes his own career as an “expositor” of math in print and on radio. He tell us he is known as the Math Guy in America (hence the misspelling of maths throughout 😉 ). This is partly why he is so interested in Fibonacci, since he too was an early expositor of arithmetic.

**Example: ****6X + Y = Z
**

**If X = chocolate truffles and Y = FF, then find Z. Answer below.**

Real name, Leonardo of Pisa, (Fibonacci was a nickname given to him by a much later mathematician), his fame rests mainly on his major work, *Liber Abbaci (The Book of Calculation)*, which explained the Hindu-Arabic number system (the use of numerals 1-9). Prior to this, arithmetic in the west had relied on an elaborate finger-counting system or the use of the abacus, both of which required a high level of skill. The system of using numerals was easier to learn and also provided a written record, hence an audit trail. Although Leonardo was not the first man to introduce this system to Europe, his book appeared just at a point where trade was about to take off exponentially in the region, so became hugely important and influential. Leonardo also wrote a follow-up book that included many worked practical examples, so that it could be used as a basis for learning how to use arithmetic even by people who weren’t interested in understanding the underlying principles. This was hand-copied thousands of times and was translated into many different regional languages and with the examples converted into local currencies, making it the most important text for spreading the use of arithmetic throughout Europe and beyond.

Devlin intersperses this information about Fibonacci with descriptions of how he, Devlin, went about researching his earlier book. This is sometimes interesting – Devlin writes well when, for example, he re-imagines the Pisa of Leonardo’s time: a trading hub, with sea-transported goods being brought into the town via the river Arno. But there are also parts where my interest level fell away almost entirely – for example, when he gives immensely detailed accounts of visits to libraries to look at ancient manuscripts, and includes blow-by-blow accounts of conversations with librarians about opening times, etc. Leonardo’s work was almost forgotten for centuries till a few researchers brought him back to prominence, and Devlin gives the story of them and their researches too. Again, these accounts varied in interest level, but overall I felt Devlin was trying too hard to make it seem more exciting than it either was or, indeed, needed to be.

When it comes to the arithmetical stuff, Devlin explains things simply enough for my decidedly non-mathematical brain to cope with. He gives some of Leonardo’s worked examples, which taught me two things: 1) I’ve forgotten what little algebra I ever knew and 2) thank goodness for Excel. However, I was pleased to see I can still usually get to the right answer eventually with my own elaborate finger-counting method (which also involves sticking out the tip of my tongue – a widely-recognised technique which oddly both Fibonacci and Devlin overlook), so this will undoubtedly be a handy skill after the apocalypse…

In the end, I suspect I might have been better reading Devlin’s earlier book rather than this one – the meat of the story for me was Leonardo’s achievements, and the rest felt a little extraneous. However, I certainly got enough out of it to make it a worthwhile and informative read overall, and the other aspects of it may appeal more to people who are intrigued to see how a biographer goes about his research process.

**Answer: Z = 0
( *throws out empty chocolate box*)**

NB This book was provided for review by the publisher, Princeton University Press.

Hmmm…this does sound interesting especially seeing that my final year university research paper was on Fibonacci and the Golden Section in music and art in general. Weird that you’ve just posted this and I actually found my paper a few days ago. The universe works in weird ways.

Oh, you might find this interesting then, but you might actually find his original book better – I get the feeling that’s more about his actual contribution to maths than this one is. Ha! Perhaps it’s sending you a message… *cue spooky music*

oooh….oooooh….(think ghost sounds).

Will look for the original…I’ll start at the very beginning, a very good place to start (sorry, couldn’t resist).

Haha! Sounds like you might be sixteen, going on seventeen… 😉

I can see why this had your interest in some places, FictionFan. I think I would find those bits interesting, too. But you have a point about weaving some disparate things together. It’s not easy to do that and still have a seamless book. Still, good to know that he was able to explicate some mathematics in ways that a non-maths person could understand. Trust me, I need that.

Ha! Yes, I’m not the most mathematically-minded person in the world myself, so I was glad he was able to explain it all simply enough for me. I did feel some of the other stuff was filler though, but there was enough good stuff in it to hold my attention. And at least now I know why Fibonacci is sorta famous…

Only you could make a book review of the research of a mathematician hilarious!

I thought Liber Abbaci was the name of a flamboyant singer/pianist.

(Okay, so that’s not a great joke. For anyone who reads this and is totally confused, Google Liberace.)

Hahaha! I wish I’d thought to add a picture of Liberace now! 😆

I must admit I felt this review needed a bit of humour to spice it up – I’m not sure how many of my visitors have a burning passion for ancient mathematicians… 😉

I’m really not one for maths so this isn’t for me. I can totally get on board with your equation though 😀

12X + 1MB = 6G

(where X = chocolate truffles, MB = Madame Bibi, and G = hours at the gym to work it off)

Oh dear, this is where the equation loses its application to real life, as I fear any number of G will never occur!

I knew we were twin souls!

Not my cup of tea, but I enjoyed your review a lot — and I fully appreciate your equation, too. Why didn’t our math teachers try to explain complex concepts by using chocolate???

Glad you enjoyed the review! 😀 Haha – I suppose it might be tricky when your pupils keep eating your props… 😉

I read a book recently called The Joy of X. For a brief -a very brief! – few moments I actually felt that, if I had been better taught, and much cleverer, I might actually have understood algebra. Geometry, however, will always remain a complete mystery! 🙂

I seem to remember being OK at basic algebra, but geometry is just silly. And as for calculus – pah!!

Your equation is the closest I’ve ever got to understanding Algebra. I read a small section of a book recently which explained Fibonacci’s Sequences, but it was too complicated for me – frustrating because the idea of this appearing in nature is fascinating. Perhaps the author’s earlier book might give me what I want without frightening me with the maths.

I reckon all equations involving chocolates eventually come to the answer zero – FF’s Theorem. This book explained Fibonacci’s Sequence too and I vaguely understood it at the time, but I fear it’s gone again… this is why life is a constant source of surprise to me… 😉

Your brave for even attempting this book, I would have taken one look at it and said “pass”. Glad you enjoyed it too 🙂

I love a challenge! Plus Princeton Uni Press seem to have me on their list of “people who will review the books that normal people won’t touch”… 😉

Haha ah yes, that list$

I still have nightmares about the Friday maths tests we had at primary school. I’m not sure I could cope with this at all!

Haha! I was OK at primary school, but secondary school maths regularly had me throwing books across the room. I still think calculus was only invented to torture children…

Your chocolate equations are about the only math I’m interested in, haha! I always had a complex about math and don’t think I ever had a really superb teacher who might have jarred me out of my perceptions about it. Oh well, it’s a common tale. I’m trying not to give me son any of my bad associations with math! Trying not to make disparaging comments, etc.

Anyway, kinda weird how he goes into so much detail about conversations with librarians… but it sounds like you enjoyed it well enough and got something out of it.

Haha! I reckon if they’d taught us using chocolate we’d all have been better at it! I was good at arithmetic, but I really struggled with maths. Partly because of the way it was taught – they never really explained what it was for, so I could never get all that interested in it. It was the same with science, and I regret that because it’s a subject I now find very interesting and wish I understood better.

Yes, it was a strange book but overall I feel I learned enough to make it worthwhile. 🙂

I think the image of knitting the sweater plus creating a matching scarf with the leftover yarn is a helpful one. No one wears matching sweaters and scarves, so the superfluous nature of this book is immediately evident. And now I miss snow. Your review also reminded me of what some people are saying about the new Al Gore movie, An Inconvenient Sequel. I want to see it NOW. I want to know what has changed since his 2006 An Inconvenient Truth came out–because I know the answer is A LOT. Based on the trailer of the new film, I see some things from the guy who claims to be the U.S. president , too. However, some reviewers are claiming the film is simply used to address naysayers of the first film. I say, uh, yeah, do it! That’s how academic discourse works! You have conversations!

Hahaha! They did in the Scotland of my youth before we all got cars with heating! And matching gloves and hats too if we had enough wool left! 😉 Yes, I certainly don’t think one film about climate change a decade ago is enough. The arguments have definitely moved on, so I like to read a new book on the subject at least every couple of years to keep up to date. And with a climate change denier in the White House, it’s more important than ever to keep the discussion in the forefront of people’s minds.