If you're going to read this book, start with the "Translator's Afterword" which really should be at the beginning.
Reading this book was a strange and not especially pleasant experience, which I think would have been true even back in 2016, when it was first published in China. Reading it in 2023, I couldn't help seeing it through COVID-colored lenses. I saw it as a metaphor for the brutality and oppressiveness of the COVID lockdowns, how entire cities became focused on protecting the narrowly defined health of the populace to the detriment of their spiritual and mental health, and even to the detriment of their physical health by any definition other than viral infection. That view point was enhanced by passages about genetically modified viruses escaping from the lab, and by the almost god-like figure, Dr. Bauchi.
Interestingly, although the Chinese version of the book was written in 2016, much of the translation was done in 2020, and as the translator, Michael Berry, describes it, the translation process involved much re-writing and creating new material (Han wrote this new material both in English and his native Chinese), and I do imagine that some of this new material was influenced by the COVID lockdowns that both Han and Berry were experiencing. On the other hand, the overall concept predates COVID, as does, apparently the name "Bauchi" (that character is apparently named Dr. Hua Yue in the published Chinese version, but the name Bauchi comes from an earlier draft, prior to 2016).
Beyond the COVID angle, there are wide ranging ideas stemming from the the medicalization of society. Yang Wei, the protaganist, argues that after undergoing gene therapy, a patient is no longer genetically the same person, and is no longer genetically related to their parents, children or other family members. Genetic engineering and in vitro fertilization eliminate the need for sexual reproduction, and eventually eliminate the need for sex. Sexual contact between people becomes therapy without pleasure, and this eliminates the impact of rape or incest.
Later the parasite that infects him presents the idea that we are all born terminally ill, and that the universe is also a terminally ill organism, infected by all life forms, which are merely pathogens. Or I might be mixing up what the parasite says with what the doctors in the underground labs say. I don't really have an interest in wading back into the book to clarify any of my impressions.
I don't have a deep enough understanding of Buddhism to know if these are Buddhist concepts taken to an extreme, or turned upside down and inside out, or perhaps it's an offensive bastardization of Buddhism. At any rate, Buddhist philosophy runs deeply through the book, and a Buddhist reading it would experience it very differently than I would. I paused a couple of times in reading to look up specific figures, and to read about philosopies, but I wasn't enjoying the base text enough to get excited about the process of figuring out what he was talking about. Maybe if the book were half as long, or a third as long, it would have lent itself to a more intense or thoughtful reading experience, but there was so much of it, that eventually I just decided to slog through it to see if anything happened in the end to put it into perspective.
The answer is no; there is no pay off in the end. My three-star rating is sort of arbitrarily chosen. Can I recommend this book? Not really, but it's certainly more thoughtful and intelligent than most of the two-star or one-star books in my library. If you have a group of friends with a strong interest in modern China, and a deep understanding of Buddhism, and you're all willing to wade through this lengthy rambling text about unpleasant experiences, you might find it leading to some interesting conversations. On the other hand, if you typically read for fun, you'll probably want to stay away from this book.