In its fourth edition, Economics Explained continues its announced purpose--to explain that mysterious thing called economics--with a new urgency.

It is announced in the first sentence of the introduction: "Just in case the reader-to-be hasn't noticed, disturbing things are going on in the American economy these days."

This new edition is about these disturbing things: a trend toward inequality of incomes, the appearance of a new "globalized" capitalism, the "specter" of inflation. As before, Robert Heilbroner and Lester Thurow treat these problems in language that seeks to...