For all their shared boundaries, the experiences of fiction and nonfiction are fundamentally different. In the traditional short story or novel, a fictive space is opened up that allows you the reader to disappear into the action, even to the point of forgetting you are reading. In the best nonfiction, it seems to me, you’re always made aware that you are being engaged with a supple mind at work. The story line or plot in nonfiction consists of the twists and turns of a thought process working itself out. This is certainly true for the essay, but it is also true, I think, for classic nonfiction in general, be it Thucydides or Pascal or Carlyle, which follows an organizing principle that can be summarized as “tracking the consciousness of the author.” What makes me want to keep reading a nonfiction text is the encounter with a surprising, well-stocked mind as it takes on the challenge of the next sentence, paragraph, and thematic problem it has set for itself. The other element that keeps me reading nonfiction happily is an evolved, entertaining, elegant, or at least highly intentional literary style. The pressure of style should be brought to bear on every passage. “Consciousness plus style equals good nonfiction” is one way of stating the formula.