I think Anathem might have been written with me in mind. I mean, it's an SF novel, but it's also chock full of philosophical dialogs between monks. Who is the target audience for that if not me?
There are few authors from whom I'm willing to read 900 pages. Fortunately Stephenson rewards that kind of investment well: Anathem takes place in an immersive world, and at various points in the story I was reminded of some of the best such immersive worlds in SF/F: Gormenghast, Perdido Street Station, His Dark Materials, and Dune, to drop just four names. Stephenson knows how to draw you in: he gradually introduces an entire vocabulary, and within a hundred pages or so you're thinking in the character's words. When those characters start presenting the book's bigger ideas, packaged in Socratic dialogs, it's hard not to be pulled into the worldview of the avout theors.
What are those, you ask? Anathem takes place on Arbre, a world in which the brightest minds are "collected" into monasteries where they focus their energies on the study of pure mathematics. The monasteries, or "concents," are sharply segregated from the Saecular world; the "avout" inside their walls are only allowed to leave once every 1, 10, 100, or 1,000 years, depending on how extreme a vow they take. (Oh—some of them, like the one where Anathem begins, are also really, really big clocks.) The avout are strict empiricists, but they aren't allowed to use technology—contrast that with the "Deolaters" of the outside world who believe in God and constantly fiddle with noisy electronic gadgets. Anathem's setting is one in which the commonly-drawn division between religion and science has been reified in the millennia-old stones of the concent walls.
Things are more complicated than they seem, however. We know this from the earliest pages: after all, here it's the empiricists who have elaborate rituals and more-or-less ascetic practices. But as we learn the philosophical history of the avout the mystical underpinnings of their system start to become clear. For instance, there's Protas, Arbre's version of Plato. After comparing clouds to the shadows they cast on the land below,
He had his famous upsight that while the shapes of the shadows undeniably answered to those of the clouds, the latter were infinitely more complex and more perfectly realized than the former, which were distorted not only by the loss of a spatial dimension but also by being projected onto terrain that was of irregular shape... Returning to Periklyne he had proclaimed his doctrine that all the things we thought we knew were shadows of more perfect things in a higher world.
A thousand years before that there was Cnoüs, an architect who launched the entire history of Arbran philosophy—and, coincidentally, the division between avout and Saecular. Cnoüs has an "upsight" while looking (like Protas) into the sky, drawing a triangle on a stone tablet to illustrate his newfound understanding. He tells his two daughters, Deät and Hylaea, of his vision, but he dies shortly thereafter. The two daughters offer conflicting interpretations. Deät says that
He was seeing into another world: a kingdom of heaven where all was bright and perfect. According to her, Cnoüs drew the conclusion that it was a mistake to worship physical idols such as the one he had been building, for those were only crude effigies of actual gods that lived in another realm, and we ought to worship those gods themselves, not artifacts we made with our own hands.
Hylaea said that Cnoüs had actually been having an upsight about geometry. What her sister Deät had misinterpreted as a pyramid in heaven was actually a glimpse of an isosceles triangle: not a crude and inaccurate representation of one, such as Cnoüs drew on his tablet with ruler and compass, but a pure theorical object of which one could make absolute statements. The triangles that we drew and measured here in the physical world were all merely more or less faithful representations of perfect triangles that existed in this higher world. We must stop confusing one with the other, and lend our minds to the study of pure geometrical objects.
What lurks beneath the surface of this story is the idea that the scientific idealism of Hylaea is just as mystical as the religious anti-idolatry of Deät. Within a few pages of relating this story Erasmas, Anathem's protagonist, begins to ponder the similarities between the two conflicting interpretations, and the first 650 pages or so of the novel depicts his gradual acceptance that his belief in the "Hylaean Theoric World"—what we would call Plato's realm of forms—is a is a mystical concept that underpins the entire thought-system of the avout. Oh, other stuff happens, too—there's a dangerous Arctic trek, a kung fu brawl, an attack by mysterious aliens, and a love story. But the important stuff, the stuff that Stephenson obviously cares most about (and the stuff that interested me the most, too), is the philosophy, and that is aaaaalll about Plato. (Or Protas, at least.) And that Platonism leads the story into a lot of science—everything from orbital mechanics to quantum computing to volcanology has a moment in Anathem's pages. But Erasmas comes to the conclusion that it all hinges on the Hylaean Theoric World, something "non-spatiotemporal—yet believed to exist."
Of course, the idea of what a more ideal universe might be gets called into question, too. I doubt Plato envisaged the form realm's inhabitants entering our universe and declaring war. (That's not exactly what happens here, but I don't want to say too much...) There are some interesting perspectives on the religious beliefs of the Deolaters along the way: for instance, the followers of the Warden of Heaven, who hold some messianic ideas about the avout, or the Kelx, who believe that our entire universe is a story being told by a condemned murderer who's trying to convince a judge to grant a stay of execution. (Bottom line: be good, or the judge will get bored of the story and cut it short by having our de facto God executed.) Erasmas offers an intriguing perspective on the Deolater's apparent nonchalance:
If you sincerely believed in God, how could you form one thought, speak one sentence, without mentioning Him? Instead of which Deolaters like Beller would go on for hours without bringing God into the conversation at all. Maybe his God was remote from our doings. Or—more likely— maybe the presence of God was so obvious to him that he felt no more need to speak of it than I did to point out, all the time, that I was breathing air.
Nevertheless, the story of Anathem involves the unification of opposites that aren't really opposites, as the Saecular and mathic worlds combine and synthesize into something greater. (In a recent interview with io9 Stephenson warned against thinking of it as an "alliance," but I think using Hegelian terminology is entirely appropriate.) In the novel's closing pages Erasmas and his circle are laying the foundations for their transformed world, establishing more open replacements for the old concents. He explains the new order's attitude to the segregation between the two worlds of Arbre:
"The rule of thumb we've been using is that Deolaters are welcome as long as they're not certain they're right," I said. "As soon as you're sure you're right, there's no point in your being here."
Questions are better than answers, and Anathem is all about inquiry—scientific and religious; philosophical and mystical. Yeah, I think I am the target audience for that.