"Claudia's Brain" is a philosophical novel about a young woman whose superpower is a clear-eyed view of truth and fiction. Through multiple heartbreaks, her remarkable intellect takes her from Cumberland Gap, Tennessee to positions of authority in the State Department and CIA, where her specialty is ferreting out nonsense. Her story is told by David Miller, who loved Claudia, but was not picked by her. "Claudia's Brain" encounters themes of...