This book functions as a companion to the six-part PBS series, "How We Got To Now." I highly recommend watching that. The book is good too, though there's something impressive about actually watching the author explain his research. He's very engaging, and clearly an enthusiast for learning. Yay for PBS!
This book/series will almost certainly reveal things that the reader didn't know, untold stories behind basic innovations that make modern life possible, in these categories: glass, sound, light, time, clean, and cold.

Johnson introduced me to an interesting phrase, "the adjacent possible." It means that inventors and visionaries have to work with the tools and concepts that are already available to them, meaning that innovation happens, not in a lightbulb moment or with a huge jump forward, but only after a lot of other people have worked in related fields first. For instance, in the mid-1800s, ultrasound was not part of the adjacent possible. But transcription of sound waves (albeit without playback) was. Smaller developments expand the adjacent possible until you get to the memorable, world-changing inventions.
Johnson also acknowledges that the development of technology almost always leads to unforeseen uses. On the same subject of sound waves, he highlights that ultrasound is responsible for saving millions of lives in ships on the ocean, but it has also enabled millions of gender-based abortions in China.
This is a particularly somber example of the connections Johnson makes, but the book is not heavy or depressing at all. It is interesting and sometimes very unexpected, even funny!

I enjoyed the conclusion where he talks about Ada Lovelace. I knew something about her, as her story has gained a bit more notoriety in recent years, but the details were super interesting. She was the daughter of the scandalous Lord Byron, the man who was labeled "mad, bad, and dangerous to know." (A phrase that has stuck in my mind for years!) To counteract her father's profligate "romantic" influence, Ada's mother insisted she study mathematics. She had a genius aptitude for it, and when Victorian wifehood and motherhood began to pall, she made her skills available to the inventor of an "analytical engine" and basically became the world's first software programmer. The fascinating part is that the machine that could read such code wouldn't be actually built for another century. As Johnson says, it was "trying to build a digital-age computer with industrial-age mechanical parts." Like Leonardo da Vinci designing a helicopter. Not in the realm of the adjacent possible. But brilliant anyway.

Took me a while to settle into "nonfiction mode," but once I did the pages flew by. I finished four of the six sections in one day. ( )

Entertaining. A bit more narrative and a bit too little engineering for my taste, but well written. ( )

Great premise of how one invention gives rise to a whole host of unintended offshoots. The chain of how thigs all connect, while simple, is not something I spend a lot of time thinking about so I appreciated the brain exercise. ( )

3.5 stars

This book looks at connections in inventions – one thing had to be invented or discovered, which created a chain reaction for the next thing and the next thing, etc. Glass, then spectacles, then the printing press caused more people to need spectacles, then microscopes, etc.

I found this interesting – the connections more than how the things were invented. Many inventions would have happened even if the person who invented had not been the one to do so – someone else would have done so soon after. I listened to the audio. The narrator was mostly fine, but there was the occasional odd pause that was noticeable, though the content was enough to (mostly) keep my interest in the book, anyway. ( )

Interesting - it was nice to hear the progression of inventions, the background setup and the ramifications. ( )