There have been no end of reviews of Thomas Piketty’s new book, Capital in the Twenty-First Century.

Perhaps the very best of them is that of Larry Summers (who should be, still, either the Treasury secretary, or the Head of the Federal Reserve Bank, or both, while serving as the president of Harvard).

Here are just the final three paragraphs of his article, The Inequality Puzzle, appearing  in the spring 2014 issue of Democracy, A Journal of Ideas.

Why is inequality so great a concern? Is it because of the adverse consequences of great fortunes or because of the hope that middle-class incomes could grow again? If, as I believe, envy is a much less important reason for concern than lost opportunity, great emphasis should shift to policies that promote bottom-up growth. At a moment when secular stagnation is a real risk, such policies may include substantially increased public investment and better training for young people and retraining for displaced workers, as well as measures to reduce barriers to private investment in spheres like energy production, where substantial job creation is possible.

Look at Kennedy airport. It is an embarrassment as an entry point to the leading city in the leading country in the world. The wealthiest, by flying privately, largely escape its depredations. Fixing it would employ substantial numbers of people who work with their hands and provide a significant stimulus to employment and growth. As I’ve written previously, if a moment when the United States can borrow at lower than 3 percent in a currency we print ourselves, and when the unemployment rate for construction workers hovers above 10 percent, is not the right moment to do it, when will that moment come?

Books that represent the last word on a topic are important. Books that represent one of the first words are even more important. By focusing attention on what has happened to a fortunate few among us, and by opening up for debate issues around the long-run functioning of our market system, Capital in the Twenty-First Century has made a profoundly important contribution.