From the Knowledge of Economics to the Economics of Knowledge:

When Professor Perlman asked me to write this paper, he charged me with discussing the connection between the Knowledge Project, the monumental ten-volume effort Fritz Machlup left unfinished at his death, and the doctrine of praxeology taught by Ludwig von Mises, Machlup's teacher in Vienna. The idea of an intellectual journey instantly sprang to mind: this would be an essay about Machlup's travels from the narrow confines of praxeology (the knowledge of economics) to the broad fields of the knowledge society (the economics of knowledge). This is still an intellectual travelogue. But, as I eventually came to realize, there are two very different kinds of intellectual journeys. The most familiar is the sort we associate with, for example, the doctrine of the "young" Marx and the "older" Marx. A scholar follows through his life a path that, while logical in each step, ultimately leads him to a position not only different from but possibly inconsistent with his original standpoint: it is