American Scientist

THING EXPLAINER: Complicated Stuff in Simple Words. Randall Munroe. 64 pp. Houghton Mifflin Harcourt, 2015. $24.95.

Take one part The Way Things Work, one part simple-English Wikipedia, and one part dry humor; mix them together with some stick figures; and you get Thing Explainer: Complicated Stuff in Simple Words, by Randall Munroe, the roboticist-turned-cartoonist behind the webcomic xkcd and the bestselling What If? Serious Scientific Answers to Absurd Hypothetical Questions. Thing Explainer is another concept-driven, cleverly nerdy book, this time built around the simple idea of explaining “how something important or interesting works, using only the ten-hundred words in our language that people use the most.”

Munroe first explored this conceit in a widely lauded panel of xkcd in which he diagrammed the workings of NASA’s Saturn V rocket (dubbed “U.S. Space Team’s Up Goer Five”) using only the 1,000 most common English words. The panel brought together clean, blueprint-style line illustrations; his trademark stick figures; and of course the honest, oddball humor his readers have come to expect, except strengthened by his linguistic constraint. The rocket’s base, for example, is labeled, “Lots of fire comes out here. This end should point toward the ground if you want to go to space. If it starts pointing toward space you are having a bad problem, and you will not go to space today.”

Thing Explainer expands on the concept of the “Up Goer Five” comic, covering topics ranging from the International Space Station (“Shared Space House”) to cells (“tiny bags of water you’re made of”) to pencils (“writing sticks”). You can explore the book sequentially if you like, but there’s no need to read it straight through, front to back. Each topic is a self-contained, endlessly explorable Where’s Waldo of finely detailed illustrations, hidden jokes, and of course descriptions using only words you already know. (If you’re wondering about the words on Munroe’s list, a section near the end of the book includes the full roster. He also hosts a word-checking tool on his website.) However, much of the humor in Thing Explainer derives from the simple-English names Munroe was obliged to invent for the items he describes—“sky boat” (airplane), for example, and “boxes that make clothes smell better” (washing machines)—then relishing how he revisits and reconfigures those names within the rules he has set himself. Helicopters are “sky boats with turning wings,” a jet engine is a “sky boat pusher,” and spacecraft are, naturally, “space boats.”

On certain subjects, Thing Explainer soars in both explanatory clarity and entertainment value—sections on the U.S. Constitution (“the U.S.’s laws of the land”), bridges (“tall roads”), and a reprise of the Saturn V are all must-reads. Other explanations fall a bit flat (I found myself bogged down in batteries, for example), but I suspect these trouble spots arise because Munroe won’t let himself off the explaining hook lightly. It is clear that he has an honest and deep commitment to communicating how things really work, without glossing over the important parts, even if they’re complicated. And sometimes that’s hard: When you get right down to it, explaining how batteries work requires an array of surprisingly complex ideas from physics and chemistry.

In contrast, I derived by far the greatest enjoyment from his reimaginings of words and concepts I already understood well. Take the Large Hadron Collider (since I’m a physicist), or LHC, a colossal apparatus beneath Geneva, Switzerland, that smashes beams of protons into each other as part of a quest to better understand the fundamental nature of the universe. It is one of the most complex and sophisticated machines ever built. But in Munroe’s Thing Explainer, the LHC’s proton-proton collisions are simply described as “throwing pieces of air down a hallway so they hit together really hard.” Brilliantly succinct and, in essence, exactly what the machine does. If you know nothing about the LHC, however, this might not be a particularly satisfying or complete explanation.

In fact, Thing Explainer is funniest and most enjoyable when you’re already familiar with the topic being lampooned, so that you can fully appreciate the contrast between Munroe’s simple English and the science jargon you would normally hear. Although it’s certainly possible to learn about new subjects from Munroe’s explanations, I wouldn’t recommend it; nor, for that matter, is it Thing Explainer’s main purpose. “To really learn about things,” Munroe writes in his introduction, “you need help from other people, and if you want to understand those people, you need to know what they mean by the words they use. You also need to know what things are called so you can ask questions about them. But there are lots of books that explain what things are called. This book explains what they do.”

However, perhaps Munroe himself hasn’t quite identified the true success of Thing Explainer. For me, his book is much more about challenging how we label things and forcing us to think about how the labels we give things unconsciously change our perceptions of them or conceal their underlying (and often fascinating) nature. Munroe delightfully challenges us to reassess our preconceptions and think of things in new ways. A laptop is simply a “bending computer.” Fossil fuels are “stuff in the Earth we can burn.” Pens are “writing sticks,” a dishwasher is a “box that cleans food holders,” and a lock is a device that checks “whether people are who they say they are.” This perspective shift is what makes Thing Explainer most worth exploring, which means that if you don’t already have familiarity with the topic at hand, Thing Explainer becomes like an out-of-service escalator: still functional but not nearly as delightful as it can be.

We scientists (humans, really) often use jargon as a crutch—knowing a label for something can make us think we understand it, or help us convince others that we understand it, even if we don’t. One of the exercises that I have found most useful for developing and gauging actual, deep understanding in math and theoretical physics is to change all the names and symbols for the variables in an equation, theorem, or proof and then see if I can still understand it. If you can see past the labels for things to what is truly underneath, you are, as Munroe says, seeing “what they do.” And Thing Explainer is a great place to start.

Henry Reich studied math and physics at Grinnell College and theoretical physics at the Perimeter Institute for Theoretical Physics, where he was later an artist in residence. He’s the creator of the popular YouTube video series MinutePhysics and MinuteEarth.

Disclosure: As he was completing this review, Reich was approached about producing a promotional video inspired by Thing Explainer; the review went to press before any work on a video was contracted.