The Joy of x: A Guided Tour of Math, from One to Infinity Paperback – October 1, 2013

Struggling through several years of higher math in engineering school in the 1960s didn't engender a love of mathematics in me. It wasn't until years later that I began to value the beauty and elegance of mathematics. A big part of my appreciation came from mathematicians like Steven Strogatz who wrote about math for readers who appreciated the concepts but had no desire to wade into a morass of complex equations.

In The Joy of x, Strogatz has done a masterful job as our tour guide through the elements of mathematics, and he's done it without "dumbing it down" or making it just another refresher course for the subject. He presented the various mathematical elements and concepts in fresh new ways, but he clearly expected the reader to exercise their mind to understand. The reward was a new appreciation of the beauty of mathematics and for how our knowledge of the subject advanced in fits and starts over several thousand years.

The book has six parts, each presenting certain elements of mathematics: Numbers, Relationships, Shapes, Change, Data, and Frontiers. These sections represent a grand tour through the history and development of mathematics, including the practical - and some whimsical - applications. Never again will I fall into the trap of bungling the answer to the classic "If three men paint three fences in three hours, how long will it take for one man to paint one fence?" (answer: 3 hours). Now I understand why a piece of paper can't be folded in half more than 7-8 times, and how a high school junior was able to beat the record using a monstrously long roll of... toilet paper! I know how Luke could guarantee himself a win over Darth Vader in a game of laser tag (hint: it involves a conic section). For young lovers, mathematics could help in finding the perfect mate (if you make a few simplistic assumptions, that is). And if the prosecution in the O.J. Simpson murder trial had understood probability and statistics, could they have gotten a conviction?

As enjoyable as the first five sections of the book were, my favorite section was the last, "Frontiers," where the author covered topics including prime numbers, where I learned that no one has ever found an exact formula to find primes; group theory, which bridges the arts and sciences; topology; spherical geometry; and infinite series. This section presented some fascinating ideas. For example, group theory suggests how to get the most even wear from a mattress and confirms the old mnemonic "spin in the spring, flip in the fall." For topology, the famous Möbius strip is examined. I thought I understood the properties of a Möbius strip, but they're actually more remarkable than I would have guessed. And the most mind-blowing concept was that some infinities are larger than others. This finding, which was bitterly contested at the time, is brilliantly demonstrated with a parable named the Hilbert Hotel.

I don't always read all of the footnotes or endnotes in a book, but the endnotes in The Joy of x are not to be missed. There are dozens of links to websites and online videos that demonstrate or expound on the concepts presented in the book. Some of these were so intriguing that I spent a couple of hours being spellbound by them.

For anyone who's been disappointed by other math books written for laypersons, The Joy of x may be the book they've been hoping for. With keen insight, a light touch, and a bit of humor, author Steven Strogatz has written a splendid book for anyone who wants a broader understanding of mathematics.

Note: I read an advance reader copy of this book provided by the publisher through NetGalley.

Before you buy this book, take a second to examine yourself. If you always hated math, don't bother with this book. You will just use it to reinforce your dislikes. But if you have ever looked at numbers, triangles, or even google page rankings and wondered how anyone ever figured any of that stuff out, this might be your book.

=== The Good Stuff ===

* This is not a math book. You won't learn how to calculate the area of a triangle, the odds of a no-hitter or the present value of a 40 year annuity. But if you are willing to read carefully and think about the concepts presented, you will have a better understanding of how math is used to model and predict the way the world works.

* I am an Electrical Engineer, a field that uses moderate level math on a daily basis. Even though none of this material was new to me, there was some interesting ways of explaining things which I had never considered before. This always comes in handy, even among fellow techies. And there were numerous facts and observations which, while I probably could derive them myself, were interesting enough to spend some time examining.

* All the material presented in the book is certainly at the level that any high-school graduate could understand. You might not be able to grasp the nuances of the material, or be able to use the concepts to solve real world problems, but you will have an understanding of how the math works. Depending on the amount of math your have been exposed to, some topics might require the reader to think a bit to understand the concepts.

Think about a two page article that describes how an internal combustion engine works. After reading it, you might understand the basic concept operation-gas/air mixture igniting and driving pistons, which rotate a shaft, which drives the wheels. You certainly couldn't design one, or fix one, and you would not know how to drive a car. But you certainly would have a better appreciation for what goes on under the hood, and it might spark your interest to learn more.

* All of the sections are short, and err on the side of over simplification and minimal explanation. This is not a math textbook, or a history of math. It is more an overview of various topics.

=== The Not So Good Stuff ===

* Strogatz tries to do too much. As an example, the equations of James Clerk Maxwell are some of the most profound mathematical models ever conceived by the human race. They predict and allow analysis of just about anything in the world that uses electricity or magnetism. But they are not at all simple, either in conception or mathematical constructs. A three page summary of them borders on the absurd. I doubt whether any person without a decent physics and math background would ever see the beauty or elegance of them.

* The chapters all seem to need to be the same length, likely a result of the newspaper articles this material was originally developed for. As a result, some simple topics seem stretched out to fill space, while some of the more complex topics are condensed beyond usefulness.

* "Advanced" math users, such as those who have studied differential and integral calculus, analytic geometry and differential equations will find some limited tidbits, but will mostly be bored by the book.

=== Summary ===

Strogatz sets himself a fairly difficult task. He tries to write a single book, which gives introductory explanations of topics ranging from integers and rational numbers all the way to linear algebra and differential equations. He tries to do this is a "mass market" book, targeted at readers with a wide gamut of math experience.

I am not sure that is a reasonable goal. In fact, I think it borders on the impossible.

Still, Strogatz makes as valiant an attempt as possible. I believe the book is "readable" by users of advanced math, and there are enough tidbits and interesting ways of explaining things to hold their interest. The book is also simple enough that most anyone can work their way through the examples and appreciate the concepts.

I enjoyed it, but not sure I would recommend it.

It's unfortunate that math is often taught as memorization of a sequence of steps to solve a problem, without any insight or understanding of what the underlying math represents, nor realization that the underlying math was developed to solve real-world problems that are fundamental to our advancement as a society. 'The Joy of x' starts at the very basics of math and shows how each part builds on other parts. Real-world examples are given that illustrate both the need for algebra and beyond, as well as the how and why math evolved and grew. Even if you never use anything more advanced than multiplication and division, this book de-mystifies algebra and beyond, and will help move math from "a course I had to take to graduate" to a better understand of the necessity of math and how it underlies everything we do.