## Review: Here’s Looking at Euclid

I have a confession. Book reviews are hard for me to write. When I open an exceptional book, like Here's Looking at Euclid: A Surprising Excursion Through the Astonishing World of Math by Alex Bellos, I get writer's block. I get lost in the awe of the material. I respond to Math books with a feeling rather than with a bunch of words. The feeling is often awe, or joy, or wow, or some combination of them. This book triggers all of the above.

Alex Bellos is a journalist. This is his first popular Math book and it is a big hit, particular in the UK. Fifteen Amazon reviewers have given the book an average rating of 4 1/2 stars. Bellos traveled around the world meeting with people who have interesting Math-related stories to tell. A few items from the table of contents will give you a feel for the book:

Chapter Three -- Something about nothing... In which the author travels to India for an audience with a Hindu seer. He discovers some very slow methods of arithmetic and some very fast ones.

Chapter Five -- The x-factor... In which the author explains why numbers are good but letters are better. He visits a man in the English countryside who collects slide rules and hears the tragic tale of their demise. Includes an exposition of logarithms and how to make a superegg.

Chapter Six -- Playtime... In which the author is on a mathematical puzzle quest. He investigates the legacy of two Chinese men -- one was a dim-witted recluse and the other fell off the earth -- and then flies to Oklahoma to meet a magician.

The stories are entertaining and very well written. What I like every more than the good stories are the great gems sprinkled throughout the book. Here's a piece of a great review on Amazon that shares some of the gems:

Even with subjects that will be familiar to most math devotees, he adds many new interesting tidbits, e.g. if you remove all the terms of the harmonic series that contain the digit 9, the formerly infinite-summing series now sums to just under 23. "Remove all terms including ANY number and the thinned-out harmonic series is convergent." if you remove all the terms that contain the string of digits 314159, the series sums, amazingly!, to a little over 2.3 million.

And mixed in with all the interesting math bits, the author constantly adds interesting asides; Peter Roget of thesaurus fame invented the slide rule log-log scale, which enabled the calculation of square roots and fractional powers like 3^2.5.

There are five pages about sudoku puzzles. They discuss the puzzle's background and also its math; the minimum number of clues needed to produce a puzzle with a unique solution seems to be 17, because although a man named Gordon Royle has collected over 50,000 17-clue puzzles, there has never been a 16-clue puzzle and Royle has a gut feeling that none exist.

Having read so many recreational Math books I live for the gems -- those exciting tidbits that are new to me. If a book has just one gem I'm happy. Here's Looking at Euclid has a nice helping of gems.

Bellos has a real winner here. This book has quickly become one of my favorites. And, I think it will be a favorite of many people who don't think of themselves as "Math people" but who are curious enough to pick up such a book.

"Shecky R"September 23rd, 2010 - 16:45

yes, I love this book as well (it has a sort of Martin Gardner-esque feel to it!), and it’s always fun to find an author one is totally unaware of — I’d never heard of Bellos before buying this book. There are so many good popular math books around these days for lay-folk to enjoy and this one is high on the list.