I live in a university town, a place that is populated by people who consider themselves called to a “life of the mind,” and yet my friends and I rarely talk about ideas or try to persuade one another of anything. It’s understood that people come to their convictions—are in some sense destined to them—by elusive forces: some combination of hormones, culture, evolutionary biases, and unconscious emotional or sexual needs. What we talk about endlessly, exhaustively, is the operations of our bodies: our exercise routines, our special diets, what drugs everyone is taking. Twice a week I attend a yoga class where I am instructed to “let go of the thinking mind,” as though consciousness were something we were all better off without.