The role of expectations is not limited to monetary policy but is crucial in many areas of economics, as Bob showed in his later research on investme… - Robert Barro

In fact, the only person to rival Friedman for policy influence in the twentieth century is John Maynard Keynes, who had a strikingly different view of the role of government. Keynes was influential because he advocated more government intervention into what he perceived as poorly functioning private economies caught up in the Great Depression. In contrast to Keynes, Friedman put the main blame for the Depression on government failures, especially of monetary policy. Hence, the Depression did not make Friedman a fan of big government. He also found in the Federal Reserve’s failure to prevent deflation an argument in favor of monetary rules. As the world evolved— with low inflation becoming the major mission of central banks and free markets and secure property rights becoming the main policies to promote economic growth—Friedman surely won the intellectual battle.

I find it amazing now that my first economics class, taught by Alan Sweezy, used John Maynard Keynes’s General Theory of Income and Employment as the textbook. Although this book is one of the most influential works of the twentieth century, it makes a really lousy textbook. Moreover, since I now regard Keynes’s analysis as seriously flawed, it is surprising that I enjoyed the course so much. As a student, I appreciated the simple way that the Keynesian model explained the workings and failings of the overall economy. Especially appealing were the clever policy remedies, such as increased government spending and tax cuts, that Keynes recommended to combat unemployment. Too bad that I discovered later that the model was theoretically and empirically deficient!

One troublesome aspect is the place of rational expectations macroeconomics in the often political debate over Keynesian economics. At least implicitly, many people feel that what's bad for the rational expectations viewpoint is good for the Keynesian one, and vice versa. But it is hard to see how the problems in using the rational expectations approach to explain monetary nonneutrality can alleviate the theoretical and empirical shortcomings of the Keynesian model.