This book is a set of ideas about topics that are relevant to mankind’s future - not comprehensive, but an interesting set of vignettes. The book does not help solve problems (the author never claims to do so) but does offer useful perspectives. Yuval says that the future will bring us a set of problems (and opportunities) driven by technology (AI and biosciences), climate change and the threat of nuclear war and these will require new approaches and global coordination. He says our past experiences are inadequate and we falsely assume that they will come to our rescue as they usually do. He then organizes lessons across 21 topics (link to a table of contents - http://georgekelley.org/21-lessons-for-the-21st-century-by-yuval-noah-harari/).

Yuval has a knack of teasing out catchy and smart nuggets in each topic, but do not expect consistent depth or breadth across chapters. I found the chapters in the middle around politics, civilization, nationalism, etc. more rewarding once I got over some of the lighter chapters on technology. Yuval speaks well on how AI raises to the fore philosophical questions that were only mildly interesting before, but his understanding of AI progression is quite one dimensional. This is really one of the flaws of the book- the analysis, even when done well, picks only a few aspects and ties them well, leaving many other relevant aspects aside. Further, while breaking the lessons into these 21 aspects and how they can play out helps to treat them well, one can’t help wondering if the real world really works that way – aren’t they are heavily tied together and influence each other? I am curious about how they all link together – maybe that would be his next book. Overall, what this book offers far outweighs what it misses, even if one doesn’t have to always agree with all of it.