This book is in a lot of ways more of everything that Three Body Problem was. It's a huger sweep, a pretty intense exploration of how getting thrown into responsibility can break people, and it builds on a lot of the ideas of the first book about how ununified people would be in response to a threat like this - stuff that now looks rather prescient after a year and a half of covid. It does also suffer from the same weaknesses, perhaps even intensified. In particular there's not much dialogue that is really characters being theirselves as opposed to Liu exploring an idea through his characters. But the good parts were so compelling that this was far from ruining the book for me.

I was left with a few questions, two of which seem like weaknesses of the book: 1) Why did Ye pick Luo to have the conversation with that she does in the preface? 2) How did any other humans know that Luo would be important? (that conversation with Ye explains Trisolaris's interest - clearly they'd have been surveilling her intensely) 3) How is there a third book? Three Body Problem left the story with an obvious lead in for a sequel, but the ending to this book could have been a series ending. I am now intrigued and want to see where Liu takes this next.