A collection of essays about international trade seems destined to be a snoozer, but Paul Krugman, an economics professor at the Massachusetts Institute of Technology, somehow manages to write about an arcane subject in a lively manner that is actually entertaining. Krugman contends that many who are famed as experts on world trade actually misunderstand the subject completely, and he provides a startling commentary on some notables, from Lester Thurow to Ross Perot. Yet Krugman comes not merely to destroy; a reader can gain from his essays some real insight into economics, not to mention which economic commentators know their stuff.