I'm not sure any of my novels have any one big idea. I like the concept of a humongous idea striking suddenly, after months or possibly years of lying around doing not much at all, allied with the popular belief that post-lightning all you have to do is retreat to a darkened room and bash out the words, a kind of a minor bureaucratic tidy-up after the brilliance of the lightning bolt.
Maybe it does work like that for some writers. But for me the ideas are more like sparks of static electricity. Mostly small, and myriad, and occasionally annoying. They are also not random, but generated by the act of writing (in which I would include daydreaming, note-jotting and open-mouthed musing to say, the neighbourhood cat). The writing generates more ideas, in turn inspiring more writing, which generate more ideas and so on.
In the case of A Confusion of Princes, it would need the psychoprobe of classic science fiction to identify and separate all the ideas and the seeds for those ideas. This is because it took me a long time to write this book, while I was also writing other books, so I can't remember. (To tell the truth, even when I write a book quickly I find it difficult to identify the genesis of any particular idea. Usually I just make something up that sounds plausible.)
