Paradigms versus Communities of Practice

It is a long time since I last read Thomas Kuhn's The Structure of Scientific Revolutions. I recall that he proposed that a scientific revolution be seen as a change in the paradigm of a field of science. As normal science illuminates the field, more and more anomolies are discovered, and the field enters what might be seen as a crisis. Eventually someone, or a small group of scientists discover a new approach. More and more scientists are enlisted to the new approach, and fewer and fewer adhere to the old, until one can consider that a new paradigm has replaced the old. The paradigms then differ not only in the basic theories that motivate research, and in the communities of practioners, but also in the problems that appear interesting, methods, etc.

I have been reading David Warsh's Knowledge and the Wealth Of Nations. It is a history of the development of economic growth theory. He follows others to differentiate between those scientists (economists in this case) motivated primarily by desire for knowledge and understanding versus those motivated by a desire for tools to solve problems -- a difference between a "purely scientific" approach and an "engineering" approach.

Perhaps it is because the economic problems have been so oppressive, but it seems that many of the best known and most influential economists have wanted knowledge to enable them to better engineer the economy and solve economic problems.

In any case, Warsh describes a scientific world in which clusters of economists form, often in a single location such as a university department, and work on a common program. These communities seek out fields of inquiry which are relevant to pressing problems of public policy, that also appear fruitful for obtaining results.

The perceived fruitfulness of a topic depends on the economics that has been done before, and the theory and methods that have been developed. Warsh's discussion emphasizes, however, the importance of borrowing from other fields. In economics, there has been a great impact of new mathematics and of computers; surprisingly often, outsiders such as John von Neumann or John Nash have made important contributions to economics.

Warsh shows us a number of what we might consider as "communities of practice" working simultaneously in economics, without necessarily challenging the existing paradigm of that field. The various communities might indeed challenge each other intellectually and for political influence. But they are not seeking something so fundamental that it might be termed a change of paradigm.

It seems to me that Warsh's insight as to the importance of these communities and the motivations for their practice is important. It is an insight that might be explored in other fields of science.

As an aside, the fall of Communism and the triumph of Capitalism, including the emergence of "The Washington Consensus" seems to me like a change in paradigm. However, the more important change was of the social and political paradigm that followed the change in intellectual economic paradigm.