Open Christopher Sims' Web site and you'll find a brilliantly colored painting, titled “Regimes, switching.” Hold your cursor over the painting, and a suggestion appears: “Graph colored and turned sideways to look like a Navajo rug?”

Intentionally or not, the “rug” illustrates the Princeton University economist's unique approach to economics. He takes conventional wisdom, spins it, examines it through a different prism and extracts a new picture—sometimes quite striking—of reality.