The Joy of X, by Steven Strogatz

Math is hard. It’s complex. It’s abstract. It’s often not very intuitive. It’s a series of numbers, signs, squiggles, and letters. With all these obstacles, it’s pretty understandable why people run away from math as soon as they can (I made it through college calculus before tapping out).

But math runs the world. It underpins everything from your grocery shopping to your banking, from Google’s search tools to GPS satellites.

Math’s fundamental importance has continued to intrigue me and periodically beguiles my curiosity, leading me to potential gateways back to math.

On one of these occasions, I stumbled upon a book that had a description that drew me in. The book, The Joy of X, purported to make mathematical concepts accessible to non-mathematicians. And, more importantly, it promised a journey that would bear no resemblance to the dry math classes that you and I may have sat through.

This premise got my attention, but what sealed the deal was the author. The book was written by Steven Strogatz, a professor of applied mathematics at Cornell. I wanted to see how an expert of his caliber would translate complex and abstract ideas into manageable bits of information for an everyday audience.

The book grew out of a series of New York Times popular science articles Strogatz had written on math, and it’s organized to mirror how we would be exposed to math in school, starting with kindergarten concepts moving all the way to theoretical mathematics being studied in the ivory tower.

It was refreshing to revisit some basic ideas that I either took for granted as an adult or never learned the details behind. The book starts by asking us to think about a pretty basic question: what is a number? Strogatz describes the philosophical background of numbers and how each building block of math helped force us to invent a new layer. For example, if you have numbers, pretty soon you need addition. Strogatz explains that we have the creativity to invent new mathematical concepts but are then locked into the systems we create by logic. He describes that once we have a concept of what “6” and “+” mean, then the meaning of 6+6 is predetermined and must be solved by the logic in the system. This, according to Strogatz, is the dichotomy of math: we invent new concepts, but then must discover the consequences. I had never thought of math this way: math was just a tool to solve problems, whether you were calculating a tip or working on particle physics. But Strogatz was proposing that math is a journey of creation and discovery.

The successful reframing of math as a field of discovery was an excellent way to pull a reader like me further into the book. Every section and every chapter have a link to this process of creation and discovery.

My favorite section in the book was about geometry, a field of math that was created to measure land for fields and farming (which makes sense if you think about the origin of the word “geometry”). As geometry was constructed, novel ideas sprouted, including concepts around cones, parabolas, circles, and pi.

This also led to new math around triangles, including the Pythagorean theorem. In school, we’re taught that the Pythagorean theorem is used to calculate the length of a right-angle triangle’s sides. But Strogatz presents this concept in a way that I was totally unfamiliar with, a way that was eye-opening and so much easier to grasp than what I had learned in school. Through an excellent use of simple pictures and diagrams, he walks through a conceptual proof of the theorem that was fundamentally illuminating. I will never think of the Pythagorean theorem in the same way again.

Strogatz continues this accessible and informative approach as he describes concepts in algebra, calculus, statistics, and theoretical mathematics. Throughout the book, it was nice to be presented with concepts I was taught in school from a different angle, which gave me a stronger appreciation of the subject matter. When the book reached mathematical concepts that I was never exposed to, Strogatz’s superb writing and clear diagrams helped distill these complex ideas into manageable pieces without feeling like he was dumbing things down or talking down to me.

It was interesting to see how Strogatz, as an expert in his field, was able to translate his knowledge into writing for a general audience. That he was able to do so while maintaining clarity and humor was all the more impressive. His writing style played a big part in keeping me hooked and kindling my desire to continue reading. His well-constructed writing, combined with an understanding of his audience’s needs (like knowing when his reader would be hungry for a diagram), helped him convey his potentially complicated material. A lesser writer – like me – would have easily stumbled. The bar he set is something to strive for.

Overall, The Joy of X was a pleasure to read. I learned new things, saw how an expert can communicate complicated ideas, and had fun at the same time. It’s hard to ask for more from a book.

This was the March 2020 selection for the Dan & Andy Book Club, a two-person book discussion “club” that was formed mostly as a way to keep two former college roommates in semi-regular contact and encourage each other to read more. Additional book selections may be discussed in future posts.

Thanks to Todd Festerling and QIAGEN for sponsoring the blog.