Neal Stephenson's Seveneves is really two or three books. The first part begins with a great opening sentence: "The moon blew up without warning and for no apparent reason" (p. 3). The rest of part one details the dystopian realization that this event will cause worldwide devastation in a few years and the actions taken by the human race to get a portion of itself into space. Part two covers the first few years of the survivors' activities in space, which leads, after 500 pages, to the first really philosophically interesting moment of the book (more on that later). Part three begins with another nice line: "FIVE THOUSAND YEARS LATER" (p. 569). I have to imagine Stephenson chuckled to himself as he wrote that. This part deals with the descendants of (some of) the humans in part two and their return to Earth.
The radical break between parts one and two on the one hand and part three on the other hand seems to have annoyed some reviewers. They really do feel like different books. Part three reads like a distant sequel that happens to be set in the same universe rather than a third part of a single book. Unlike most reviewers, I liked the last part of the book a great deal more than the first two parts, because it gets more into wild Big Ideas SF, whereas the first two parts are much more bogged down in the technical details of Engineers' SF (more on that distinction here). Perhaps if Stephenson weren't already a famous writer, the publisher would have insisted he publish this as a duology or trilogy instead of a mammoth single volume (and it is mammoth where, to play on the ice age metaphor, a mere giant sloth would do).
This is only the second Stephenson book I've read, the other being Snow Crash. I don't really understand Stephenson's extreme popularity within and without the genre, but perhaps I lack a large enough sample size to make that assessment. Seveneves is a very different book than Snow Crash, but I still get the sense that Stephenson is the kind of nerd who secretly thinks he's cool. He's a nerd for the Silicon Valley crowd.
This sounds like a weird thing to say about an author who spends at least 100 of the 861 pages of the book discussing the minutiae of orbital mechanics to a degree that we non-NASA engineers find mind-numbing, but it often seems that Stephenson is doing all that mostly to show off to the reader how smart he is. Anyone familiar with a certain type of insecure white male nerd will recognize such a gambit. Occasionally Stephenson also veers into insecure male nerd territory in his treatment of female characters and vaguely sociobiological depictions of male sexuality.
Perhaps the greatest fault of a book this long and complex is that it lacks a glossary. Stephenson loves coining new terms and using complex engineering terms, but I had trouble remembering them. I thought about making my own glossary just to keep track of it all. Of course I didn't think to check until after I finished the book, but the predictably cool website for the book does have a small glossary that focuses on the first two parts.
Despite my complaints about the length, unnecessary level of engineering detail, lack of a glossary, and nerdier-than-thou style, there's a lot of cool stuff in this book. Parts one and two are engaging and enjoyable as fairly standard hard SF. Part three gets into some wild stuff and sets up a really interesting far future society based directly on the events of the first two parts.
The Philosophy Report
For a book this size and an author of this reputation, I found most of it to be relatively philosophically shallow. People scramble to get everyone into space and to survive, but there's little reflection on what it all means. Maybe this is a realistic portrayal of how scrambling leaves no room for reflection. I'm not sure. It wasn't until about 500 pages in that I actually felt impelled to think seriously about something other than orbital mechanics and two-dimensional politics. Discussing this moment requires, however, enough delta vee to push us into spoiler orbit.
WARNING: SPOILERS AHEAD!!! At the end of part two, the humans finally make it to a big enough part of the former moon to provide adequate shelter. Also, though a series of mishaps, the entire human race (as far as we can tell) is reduced to eight people, all women, seven of whom are able to have children. Hence, we have the Seven Eves of the title. Somehow in all the bustle they neglected to get sperm samples before all the men died, which seems like a weird oversight for a small group trying to preserve the human race, but whatever. Luckily, a geneticist has survived who is able to induce pregnancy without fertilization (a process called parthenogenesis, one of those words I would've put in the glossary). Also, the geneticist tells each of the Eves that she can make changes to their offspring.
So we finally have some meaty philosophical questions after 500 some pages: if you were to reboot the human race, what changes would you make to human nature? What criteria would you use to decide? Is it right to alter future generations?
One Eve wants her offspring to have fewer aggressive impulses. Others reject this idea. Another wants her offspring to be disposed to martial discipline. Another wants aptitude for political acumen. Another wants a few different strands to compete with the others. And so on. How would you remake the human race? The fun of Seveneves, and why I'm willing to forgive most of its many faults, is that we get to see the long term results of these choices in part three in a society where there are seven different kinds of humans. Well, there are actually more than seven - anywhere from nine to thirteen depending on how you count it. My favorite are the Neoanders, who are part Neanderthal. There are also surprisingly two sets of humans who survived the devastation on Earth. One wonders what became of the contingent that set out for Mars in part two...
I can't resist mentioning a nice moment at the very end of the book where, after 5,000 years, somebody finally gets around to wondering again what caused the moon to blow up in the first place and what this may portend for the human race(s). This shows that Stephenson does have some philosophical depth, but he takes many hundreds of pages to tap into it.
So, this is a book with plenty of faults, but also a book with a lot of cool stuff going on. Kind of like humanity.
Parts One and Two: 75/100
Part Three: 90/100
(See my Goodreads review)