Bellos - Heres looking at Euclid: a surprising excursion through the astonishing world of math

A SURPRISING EXCURSION
THROUGH THE ASTONISHING
WORLD OF MATH

Alex Bellos

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Copyright 2010 by Alex Bellos

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First Free Press hardcover edition June 2010

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Library of Congress Cataloging-in-Publication Data

Bellos, Alex, 1969
Heres looking at Euclid : a surprising excursion
through the astonishing world of math /
Alex Bellos.Free Press hardcover ed.
p. cm.
1. Number concept. 2. Numeracy.
3. Numbers, RationalSocial aspects. I. Title.
QA141.15.B35 2010

513dc22 2009036815

ISBN 978-1-4165-8825-2
ISBN 978-1-4165-9634-9 (ebook)

To my mother and father

In which the author tries to find out where numbers come from, since they havent been around that long. He meets a man who has lived in the jungle and a chimpanzee who has always lived in the city.

In which the author learns about the tyranny of ten, and the revolutionaries plotting its downfall. He goes to an after-school club in Tokyo where the pupils learn to calculate by thinking about beads.

In which the author almost changes his name because the disciple of a Greek cult leader says he must. Instead, he follows the instructions of another Greek thinker, dusts off his compass and folds two business cards into a tetrahedron.

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.

In which the author is in Germany to witness the worlds fastest mental multiplication. It is a roundabout way to begin telling the story of circles, a transcendental tale that leads him to a New York sofa.

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.

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

In which the author is first confronted with the infinite. He encounters an unstoppable snail and a devilish family of numbers.

In which the author meets a Londoner with a claw who claims to have discovered the secret of beautiful teeth.

In which the author remembers the dukes of hasard and goes gambling in Reno. He takes a walk through randomness and ends up in an office block in Newport Beachwhere, if he looked across the ocean, he might be able to spot a lottery winner on a desert island in the South Pacific.

In which the authors farinaceous overindulgence is an attempt to savor the birth of statistics.

In which the author terminates his journey with potato chips and crochet. Hes looking at Euclid, again, and then at a hotel with an infinite number of rooms that cannot cope with a sudden influx of guests.

As a kid I liked math and I liked writing. So when I was a teenager it seemed totally in keeping with both passions to go up to university to study mathematics and philosophy, a joint course with one foot in science and the other in the liberal arts. At university, however, I spent most of my time involved with the student paper. While I was an undergrad I also managed to get some stories published in the British national press, including one, in the London Guardian, about why math was cool. It was the first time I wrote an article about math and the last for almost twenty years.

After graduating, I became a journalist. I felt I was abandoning the world of numbers in order to embrace the world of letters. I worked for an evening paper in Brighton, England, then for several papers in London, and eventually I became a foreign correspondent in Rio de Janeiro, Brazil. Occasionally my mathematically trained brain was helpful, such as when finding the U.S. state whose area was closest to the most recently deforested swath of Amazon jungle, or when calculating exchange rates during various currency crises. But essentially, it felt very much as if I had left math behind.

Then, a few years ago, I returned home to the U.K. not knowing what I wanted to do next. For a while I sold T-shirts of Brazilian footballers; I started a blog; I toyed with the idea of importing tropical fruit. Nothing worked out. During this process of reassessment, however, I decided to look again at the subject that had consumed me for so much of my youth, and it was there that I found the spark of inspiration that led me to write this book.

Entering the world of math as an adult was very different from entering it as a child, when the requirement to pass exams means that often the really engrossing stuff is passed over. Now I was free to wander down avenues just because they sounded curious and interesting. I learned about ethnomathematics, the study of how different cultures approach math, and about how math has been shaped by religion. I became intrigued by recent work in behavioral psychology and neuroscience that is piecing together exactly why and how the brain thinks of numbers.

I realized I was behaving just like a foreign correspondent on assignment, except that my destination was an abstract one, the world of mathematics.

My journey soon became geographical, since I wanted to experience math in action. So, I flew to India to learn how the country invented zero, one of the greatest intellectual breakthroughs in human history. I booked myself into a megacasino in Reno to see firsthand how probability underlies the gambling industry. And in Japan, I met the worlds most numerate chimpanzee.

As my research progressed, I found myself in the strange position of being both an expert and a nonspecialist at the same time. Relearning school math was like reacquainting myself with old friends, but there were many friends of friends I had never met back then, and there are also a lot of new kids on the block. Before I wrote this book, for example, I was unaware that for hundreds of years there have been campaigns to introduce two new numbers to our ten-number system. I didnt realize that origami is a