The last chapter modeled technological progress as an increase in the number of types of products, N. In this chapter, we allow for improvements in t… - Robert Barro

In contrast to Smith’s incomplete modeling, his follower, David Ricardo, provides a coherent setting— basically, the first macroeconomic model—that can be tested, modified, and applied. Although Ricardo is surely narrower and less imaginative and insightful than Smith, he is also a lot better organized. That is why Ricardo’s analysis of macroeconomics—for example, of the implications of public debt—is more coherent and useful than Smith’s.

My recent work on macroeconomics has stressed long-term issues, including the determinants of long-run economic growth. From the standpoint of fighting world poverty, nothing is more important than figuring out which policies differentiate the fast-growing countries from the slow-growing ones.

My views are more akin to the nineteenth-century liberal philosophy espoused by Milton Friedman, especially in his Capitalism and Freedom. In that work, he proposed many policies that are harmonious with free markets and are receiving serious attention in the United States and other countries. This list includes school choice, the flat-rate income tax, rules for monetary stability, privatized social security, and the elimination of affirmative-action programs.