This is a book about discernment in action, centered on the Buddha’s strategic use of discernment in framing and responding to questions. The idea for this book was born more than a decade ago from reading a number of Buddha’s discourses. The first was SN 44:10, in which he refused to answer the question of whether there is or is not a self. This discourse called attention to the fact that the Buddha had clear ideas about which questions his teachings were meant to answer, and which ones they weren’t. I realized that if I wanted to understand and get the best use out of his teaching on not-self, I had to find the questions to which this teaching was a response and not take it out of context.