Reflections of a Pragmatic Economist: My Intellectual Journey

Appendix C: A BRIEF DIGRESSION ON THOMAS KUHN’S THE STRUCTURE OF SCIENTIFIC REVOLUTIONS

229 Appendix C A BRIEF DIGRESSION ON THOMAS KUHN’S THE STRUCTURE OF SCIENTIFIC REVOLUTIONS WHAT IS A DISCIPLINARY MATRIX? Chapter 4 and Chapter 6, especially, include frequent references to the seminal work of Thomas Kuhn on scientific revolutions. The following paragraphs attempt to describe and illustrate that part of Kuhn’s model that is used elsewhere in this book. Thomas Kuhn taught that scientific revolutions and their aftermaths are not simple phenomena. A scientific revolution, according to Kuhn, is far more complex than a single flash of genius or a dramatic experiment that overthrows existing beliefs and thoughts. There are preconditions that must occur. One precondition is the existence of some part of reality that existing theory does not explain or rationalize well, but that might reasonably be expected of the existing theory. For example, the widespread unemployment that existed during the Great Depression years of my childhood could not easily be explained by the established and dominant economic theory at that time. Kuhn refers to these unexplained phenomena as anomalies. A revolutionary development will not only explain some or all of the anomalies unexplained by existing theory, it will also explain at least some of the reality covered by existing theory. The previous paragraph is accurate as far as it goes, but it is 230 APPENDIX C incomplete. How does the layperson know if a different approach has replaced existing theory? Kuhn established a practical test. An idea is revolutionary, according to Kuhn, if it is sufficiently interesting to induce other scientists to elaborate the new approach. It is important to note that “revolutions” are a relative concept. They can be large or small, major or minor. One measure of the importance of a revolutionary idea is the number of scientific workers who are willing to devote some or all of their effort to its elaboration. What does the term “elaborate” mean as I have used it here? Kuhn called the elaboration of a revolutionary discovery “normal science.” I note three aspects of normal scientific effort. One pertains to empirical information made interesting to others, who are attracted to a field because they are excited about the new way of looking at things made possible by the revolutionary development. But the collection of factual information may not be a simple matter because new techniques may be required for the collection and measurement of the new, interesting information. A second important part of normal science, then, involves instrumentation, or the technology that supports normal science investigations. A third part of normal science is what Kuhn refers to as puzzle-solving. This involves exploration of inherent, but implicit, relations within the revolutionary advance. Answers to puzzles may, or may not, have practical relevance, but they are made interesting by the revolutionary advance. Think now about the total enterprise that results from this combination of a revolutionary idea and the normal science activities that elaborate it. First is the collection and analysis of empirical information, often requiring developments in instrumentation technology, followed by the efforts to solve puzzles that arise from the revolutionary idea and the new empirical information that has been gathered. Colleges and universities develop graduate programs to involve students in existing research and to provide future personnel for research. Textbooks and literature collections may come into being and scientific journals requiring peer review may emerge to provide validation of the literature . It is this collection of activities that Kuhn describes as a disciplinary matrix. The content of a disciplinary matrix falls into two major categories. One category comprises concepts, principles, and subject- A BRIEF DIGRESSION 231 matter knowledge; the other is the infrastructure needed for the support of the other category. One reason that university disciplinary departments have been successful instruments of scientific research and graduate education is that both parts of Kuhn’s disciplinary matrix may be found under one roof. I make repeated use of Kuhn’s disciplinary matrix concept in this book. The above descriptions of scientific revolutions and disciplinary matrixes is aided by Figure 1 in Chapter 3, which classifies certain notable economists, in particular John Maynard Keynes, whose name appears below that of Alfred Marshall. Keynes was an Englishman who studied economics at Cambridge University under Marshall. Prior to the revolution in economics brought about largely by Keynes, the structure of economics is best described as neoclassical microeconomics . This means that economic decisions were assumed to be made at the margin...