Steve Jobs holds up the new iPod during the introduction of the device in 2005. (Paul Sakuma/Associated Press)

Fred Vogelstein, the author of “Dogfight: How Apple and Google Went to War and Started a Revolution,” is a contributing editor for Wired magazine.

We all know how important the printing press has been to human history. Invented in the 1400s, it allowed the mass production of books, newspapers and magazines. That fueled rapid increases in literacy and spawned new industries such as publishing. It also laid the foundation for colossal changes in how citizens expected to be governed, leading to more open and democratic societies.

But did you know that the printing press also ignited a revolution in glassmaking? Europeans wanted eyeglasses to help them read all the material that printing presses were producing. When there was little to read, few cared about the farsightedness that hits us in middle age. Eyeglasses were hard to find and expensive. But because of the printing press, an entire industry of lens crafters was born.

Soon these artisans discovered that spectacles were just one kind of lens. By 1590 they had figured out a way to use lenses called microscopes to see the tiniest of things and, a generation later, lenses called telescopes to see big things that were very far away. Telescopes helped change our understanding of how humans and the Earth evolved. Microscopes helped drive quantum leaps in medicine. Eventually, new kinds of lenses changed the definition of media, too — to include photography, movies and television.

“How We Got to Now,” Steven Johnson’s new book about “six innovations that made the modern world,” is filled with weird and amusing examples like this. His point is simple, important and well-timed: During periods of rapid innovation, there is always tumult as citizens try to make sense of it. But listen to forecasters skeptically, Johnson suggests. Big innovations create so many important and unpredictable offshoots that even the smartest seers end up being terrible at predicting how the future will evolve.

“How We Got to Now: Six Innovations That Made the Modern World” by Steven Johnson. (Riverhead)

This is helpful advice today. Smartphones and tablets, along with the software and cloud computing growing up around them, are turning the world on its ear. And the industrialized world is in the midst of massive global hand-wringing to figure out how much of this progress is good and how much is not so good. Johnson’s book reminds us that not only has modern society dealt with these problems before, these issues are endemic to progress.

Johnson professes not to have an opinion about the relative goodness or badness of the six innovations he highlights: glass, cold, sound, cleanliness, time and light. But his presentation is reassuring and provides welcome context. I’d argue that Silicon Valley is becoming as dominant a place in the American economy as Detroit was during the first half of the 20th century. The best and brightest now all want to move west to work at companies like Google, Apple, Facebook, Twitter, Amazon and Microsoft.

The problem is that while those companies are creating as much wealth as the automakers did at their peak, they employ only a fraction of the people. The automakers employed more than 1 million workers by the 1950s, when GM was the most profitable company in the world. The top tech companies by market capitalization — Google, Apple and Microsoft — employ less than 25 percent of that.

Johnson’s book made me think less linearly about this. One might have been able to predict five years ago that the convergence of high gas prices, climate change and the smartphone revolution would create an insatiable demand for better batteries. But few could have predicted that an important attempt at a solution would happen here, in the United States. Heavy manufacturing was supposed to be dying in this country. But in September, Tesla chief executive Elon Musk said that together with Panasonic, he would build the world’s largest battery plant near Reno, Nev. This plant will soon employ 6,500 people.

Johnson is an engaging writer, and he takes very complicated and disparate subjects and makes their evolution understandable. His choice of which six innovations to highlight makes an interesting statement, too. Many of us would expect a history of innovation to include various forms of power — sail, water, hydro, electric, wind, steam, gas — or the development of steel, or flight, or the elevator, or assembly-line manufacturing. But when was the last time you thought of the importance of glass to the history of the world? Or of Galileo’s pendulum clock — the first machine that could keep accurate time to the minute? “Would the industrial revolution have even happened” without it? Johnson asks. “You can make a reasonably good case that the answer is no.” The Industrial Revolution required a schedule for the delivery of materials and the arrival of workers at factories. That would not have been possible without accurate clocks, he says.

This is Johnson’s eighth book. Two have been bestsellers. The one problem with “How We Got to Now” is that even these six topics are well traveled. Perhaps no one has thought to make a book out of the importance of all six, but there have certainly been many books on the history of each. What that means is that sometimes, in an effort to simplify, Johnson goes too far and almost trivializes. He says in the acknowledgments that writing the book and creating the accompanying PBS-BBC TV series was the hardest work he has ever done. I believe him. But in an effort to keep a book with such an enormous scope at around 250 pages, he has written passages that read like Wikipedia entries.

For example, it’s not super surprising that the invention of the microphone and the vacuum tube enabled the entertainment industry. But it’s fascinating to hear that it gave dictators such as Adolf Hitler a new tool to grab power — the political rally. For the first time, Johnson says, dictators could be heard by tens of thousands, and they used their superior oratorical skills to whip crowds into a frenzy. But politics and dictators are as old as humanity. If leaders and dictators such as Alexander the Great, Napoleon, Lenin and the rest could not use microphones, what did they do? Johnson says they used the “reverberations of caves or cathedrals or opera houses,” and that “before tube amplifiers, the limits of our vocal chords made it difficult to speak to more than a thousand people at a time.” Would Hitler truly have been less of a dictator without a microphone? The answer to this question is probably more nuanced than Johnson suggests.

These failings chip away at what is otherwise an interesting, accessible book. They also create some irony. One of the points Johnson drives home again and again about innovation is that it’s almost never a simplistic tale of a lone inventor in a lab coming up with an Earth-changing idea. It’s much more complicated than that. It takes someone like Steve Jobs or Thomas Edison, who is smart enough to notice many different innovations converging at the same time and ambitious enough to build something no one else saw in those ideas. It’s rare for me to think that someone’s explanations could be more, not less, complicated. But I found myself wishing for that sometimes here.

Fred Vogelstein is the author of “Dogfight: How Apple and Google Went to War and Started a Revolution” and a contributing editor for Wired magazine.

HOW WE GOT TO NOW

Six Innovations That Made the Modern World

By Steven Johnson

Riverhead. 293 pp. $30