I got this book on the recommendation of none other than Bill Gates, who put it on his "5 books worth reading this summer". (And—ha—I finished it yesterday, just a few hours before the Autumnal Equinox.) It's one of those rare occasions where the University Near Here library owns it and it hadn't been checked out until April 2019 by some book-hoarding faculty member.
(Don't get me started… oh, wait, I guess I did start. I'll stop now.)
The book is by Walter Isaacson, previously the author of books on Steve Jobs and Albert Einstein. Isaacson is a polished writer of popular non-fiction, and this reads smoothly. Another factor was my near-total ignorance of the details of Leonardo's life. ("He was… Italian, right?") So just about everything was new and interesting to me. The book is lavishly illustrated with color reproductions of a number of Leonardo's paintings, drawings, and excerpts from his notebooks. There's a lot of analysis and interpretation of Leonardo's works. (And, since I'm totally ignorant about such things, they may even be insightful and correct, what do I know?)
What struck me most was the confluence of factors that made Leonardo into the figure we know today. Okay, fine, he was blessed with a high raw intelligence. But other features of his personality played a vital role as well: his curiosity was turned up to eleven; his powers of patient observation were unmatched; he was an utter perfectionist. (One of the things I didn't know: Mona Lisa is, technically, an unfinished painting; Leonardo worked on it for years, and it was in his possession when he died.)
Leonardo was also gay, people of his time were well aware. Also illegitimate, and who knows what role these factors played in his life trajectory?
Also vital were the time and place: Renaissance Italy. Full of prosperous merchants and rulers who had nothing better to do with their wealth than to patronize artistic and engineering genius. Portraits needed painting, churches needed decorating, armies needed innovative weaponry, … Outside of that environment, Leonardo would have become what? A notary, like his dad?
Also interesting was Leonardo's interactions with other famous folk. He had some dealings with Michaelangelo–they didn't get along. He spent some time in the employ of the notorious Cesare Borgia, a very nasty guy, but that didn't seem to scruple him much. While there, he hung around with Machiavelli, too.
Bottom line: interesting and readable. Somewhat distracting was Isaacson's occasional comparisons of Leonardo with Steve Jobs. (Page 353: "Innovation requires a reality distortion field." Really? I guess, maybe, I wouldn't know.)