I can't remember [of a good regulation]. Regulation of transport, regulation of agriculture—agriculture is a, zoning is z. You know, you go from a to… - Ronald Coase

If you torture the data enough, nature will always confess.

But a theory is not like an airline or bus timetable. We are not interested simply in the accuracy of its predictions. A theory also serves as a base for thinking. It helps us to understand what is going on by enabling us to organize our thoughts. Faced with a choice between a theory which predicts well but gives us little insight into how the system works and one which gives us this insight but predicts badly, I would choose the latter, and I am inclined to think that most economists would do the same.

The limit to the size of the firm is set where its costs of organizing a transaction become equal to the cost of carrying it out through the market. This determines what the firm buys, produces, and sells. As the concept of transaction costs is not usually used by economists, it is not surprising that an approach which incorporates it will find some difficulty in getting itself accepted. We can best understand this attitude if we consider not the firm but the market.