"Novels for me are how I find out what's going on in my own head. And so that's a really useful and indeed critical thing to do when you do as many of these other things as I do"

Cory Doctorow is recommending that novels are a way for him to explore his own ideas and feelings. He thinks that reading novels is a critical part of his life, as it assists him to comprehend himself much better. He implies that checking out books is a way to gain insight into his own mind, and that this is specifically crucial when he is hectic with other activities. Doctorow is suggesting that books are an important tool for self-reflection and understanding, and that they can be used to acquire insight into one's own thoughts and sensations. He believes that novels are a vital part of his life, which they are an useful method to acquire insight into his own mind.