This book displays all the worst things of sci-fi, it's a doorstopper, full of unnecessary strange words (there's a 20 page glossary) and superfluous Capital Letters. But it's strange, good science fiction asks us to suspend disbelief about some science advance and shows us something about human character. The conceit in Anathem is about human character and it shows us something cool about hard-core science philosophy.
I never managed to suspend disbelief. The conceit is, all scientists locked themselves out of society for several millenia in fear of what they'd done and in the pursuit of pure science. They live in tiny groups and only disseminate information between each other every 10, 100 and _1000_ years. Meanwhile society rises and falls several times outside, building skyscrapers and tanks but never once discovering science again. Yet despite only sharing the best data every 1000 years and having no practical experience, when stuff happens the world will once again rely on them to solve their problems. Every now and then an intelligent person doesn't join the maths-monks and the book tells us they're terribly out of place. Oh poor him he's intelligent but unfortunately religious. It's an intelligent mechanic! but mechanics are can't express intelligence! In a world with internet, advanced computers etc people use fuel-burning stoves because they're scared to use something they won't understand.
But this book isn't about the people in the end, it's like an ancient philosophical treaty and whilst slow, it really is tense and exciting to watch conclusion pile upon conclusion.
It doesn't even get humans wrong a religious person (everyone finds the religious annoying) even held my reviews. It just isn't about people.
Despite religion being a huge theme it never really offended me though, it just missed the point a bit. In the end a conclusion is drawn 'the more he knew of the complexity of the mind and the cosmos...the more inclined he was to see it as a kind of miracle.. more extraordinary than any of the miracles catalogued down the ages by the religions of the world' But what bigger miracle is there, when right at the start God tells us that creation is ordered? That when we looked there'd be more to this world than chaos
At the end the science loses it's way a litte. But if you can face it, it's a fascinating read.