Capital in the Twenty-First Century, by the French economist Thomas Piketty, is being hailed as "the most important economics book of the year—and maybe of the decade" by Nobel laureate Paul Krugman. The Economist says the book may revolutionize "the way people think about the economic history of the past two centuries." Ira Stoll has read it and reports that it's better than you would expect. In fact, Stoll notes, there is quite a bit in the book that free-market types can embrace. But unfortunately, Stoll adds, Piketty also ignores many of the most significant failings of modern liberal economics.