Economists (excluding those who are writing in this volume) like to think that the spread of their ideas proceeds ultimately according to some perfectly competitive model or Darwinian principle with “truth” like efficiency and fitness being the criterion for survival and success. They think people throughout society, just as the economists themselves, pick up and use economic theory that has been successfully tested and employ only analytical tools that have demonstrable utility. Similarly, they believe, society will reject falsified theory and unfruitful tools. The process of the filiation of economic ideas outside the discipline may be more complex than this.

Various groups in society outside the economics discipline use economics for specific tasks which are their responsibility: government officials to formulate and implement public policy; businesspeople to operate private enterprises efficiently in pursuit of various goals; and the media to interpret events for the public. But there is another, more amorphous, segment of society which makes use of economic ideas as well, and in several ways provides for their spread throughout the community. This segment resides in the private sector but is distinct from the various special interests such as firms, unions, and profitseeking individuals. It is the obverse of private interests; its sole declared objective is to safeguard the public interest, and the complexity of its existence is witnessed by the customary use of negatives rather than positives to describe its function: the units in this sector are “nonpartisan,” “not-for-profit,” and, customarily, “nontaxed.” What makes this sector so important in American society is that it has come to control substantial wealth originating in firms, individuals, and governments.