If Keynes was Luther, Friedman was Ignatius of Loyola, founder of the Jesuits. And like the Jesuits, Friedman’s followers have acted as a sort of dis… - Paul Krugman

The idea that a country's economic fortunes are largely determined by its success on world markets is a hypothesis, not a necessary truth; and as a practical, empirical matter, that hypothesis is flatly wrong. That is, it is simply not the case that the world's leading nations are to any important degree in economic competition with each other, or that any of their major economic problems can be attributed to failures to compete on world markets.

I do not mean to say that formal economic analysis is worthless, and that anybody's opinion on economic matters is as good as anyone else's. On the contrary! I am a strong believer in the importance of models, which are to our minds what spear-throwers were to stone age arms: they greatly extend the power and range of our insight. In particular, I have no sympathy for those people who criticize the unrealistic simplifications of model-builders, and imagine that they achieve greater sophistication by avoiding stating their assumptions clearly. The point is to realize that economic models are metaphors, not truth. By all means express your thoughts in models, as pretty as possible (more on that below). But always remember that you may have gotten the metaphor wrong, and that someone else with a different metaphor may be seeing something that you are missing.

In the course of describing my formative moment in 1978, I have already implicitly given my four basic rules for research. Let me now state them explicitly, then explain. Here are the rules: 1. Listen to the Gentiles
2. Question the question
3. Dare to be silly
4. Simplify, simplify