In 2002, Alex Bellos published Futebol: The Brazilian Way of Life to much acclaim.
Its appeal stemmed partly from its having been written by someone who had lived in Brazil and was a student of that nation's obsession with football, and partly because the subject is a sexy one. Now, Bellos is sharing with readers another of his passions: mathematics.
He realises that he has a tougher job this time for, rather than summoning up images of samba, Pele and the Copacabana, his new book, Alex's Adventures in Numberland, evokes, for many of us, less welcome memories of long hours in school classrooms staring at incomprehensible groupings of numbers on a blackboard.
Bellos, who grew up in Edinburgh and Southampton, saw it differently: "Maths was my first love when I was a kid. I studied it at Oxford (with philosophy) but then became a journalist and neglected it. I wanted to write a book for the general reader showing that it could be fun and not dry."
He decided to use storytelling techniques to bring the subject to life. "Just as I had been to the Amazon to write about football in Brazil, I flew to Japan to interview the guy who invented Sudoku and to India where the concept of zero was invented," Bellos explains.
However, for one of the most fascinating encounters in the book, the much-travelled Bellos (he is the Guardian's former Brazil correspondent) had a shorter journey - to East Finchley, the home of a retired Jewish dentist who believes there is a mathematical formula that reveals the most fundamentally satisfying, and therefore attractive, set of proportions available to human perception - including those that make up the most beautiful teeth.
"I wanted to write something about the 'golden ratio'," enthuses Bellos, "which is an amazing phenomenon. So I Googled the world's experts and it turned out the guy who had done the most interesting work was this chap called Eddy Levin.
"He invented the Golden Mean Gauge, whose three prongs are always in the golden ratio of 1.618. He invented it for teeth because he believes the most beautiful teeth are in that ratio. But it's not just for dentists - plastic surgeons use the ratio, interior designers use it, people who gamble on the stock market use it and it also appears in nature, in an incredible mathematical number sequence which can be observed even in pineapples and broccoli. Rather than cover it by going through the numbers, I thought I would tell it through the story of Eddy and his beautiful teeth, which is quite fun."
Bellos's mission seems to be to appeal to people like me, who were traumatised by bad teaching at school and have consequently become phobic about the subject. To this end, he has pitched the maths at GCSE level. His original plan was to cover all the topics in the syllabus, although during his journey through the history of numbers he veered away from this somewhat.
I may be at the extreme end of maths aversion (with a borderline version of dyscalculia, the numerical equivalent of dyslexia), but I found Bellos's story of maths fascinating and fairly comprehensible (although his claim to have made Pythagoras's theorem explicable even to dummies didn't quite work on me).
I was, however - and this is not a sentence I thought I would ever write - transfixed by the chapter on pi. Bellos is gratified: "If you tell someone that pi is really interesting they will be like, yeah, so what. But if you say you were in a room with these two brothers who think they are one person, who built one of the biggest, most complicated computers in the history of the world out of mail-order parts in their Manhattan apartment because they want to find out the digits in pi - then it becomes interesting."
