HOW SCIENCE DEVELOPS --- Episode 4

                                                                PARADIGM 

   This element needs special attention. There are two reasons for this. First, the physicist/history writer Thomas S. Kuhn, single-handedly changed the currency of the word paradigm so that a new reader attaches very different connotations to the word than were available to him in 1962, when he wrote his wonderful book, Structure.  Secondly, as Kuhn himself stated clearly in his postscript :"The paradigm as shared example is the central element of what I now take to be the most novel and least understood aspect of this book." On the same page he suggested exemplar as a possible substitute word. In another essay written shortly before the postscript, he admitted that he had "lost control of the word." In later life he abandoned it. But we, the readers of Structure fifty years after it was published and after a lot of the dust has settled, can, I hope, happily restore it to prominence. 
   As soon as the book was published, its readers complained that the word was used in all too many ways. This prompted Kuhn to clarify. The upshot was an essay called "Second Thoughts on Paradigms." He distinguished what he called two basic uses of the word, one "global" and one "local." Of the local use he wrote, " it is, of course, the sense of 'paradigm' as standard example that led originally to my choice of the term." But readers, he said, had mostly used it in a more global way than he had intended, and he continued, "I see little chance of recapturing 'paradigm' for its original use, the only one that is philologically at all appropriate." Maybe that was true in 1974, but on its fiftieth anniversary, we were able to return to the intended use of 1962. 
   By way of background, the Greek word paradeigma played an important part in Aristotle's theory of argument, especially in the book called Rhetoric.That book is about practical argument between two parties, an orator and an audience, who share a great many beliefs that hardly need stating. In English translations the ancestor of our word paradigm is usually rendered as example, but Aristotle meant something more like exemplar, a very best and most instructive example. He thought that there are two basic types of arguments. One kind of argument is essentially deductive, but with many unstated premises. The other is essentially analogical. 
   In this second basic type of argument, something is in dispute. Here is one of Aristotle's examples, which many readers will find all too easy to update from the city-states of Aristotle's time to the nation-states of today. Should Athens go to war with its neighbor Thebes ? No.  It was evil of Thebes to make war on its neighbor Phocis. Any Athenian audience would agree ; it is a paradigm.  The situation in dispute is exactly analogous. So  it would be evil for us to make war on Thebes. 
  In general : Something is in dispute. One states a compelling example about which almost everyone in the audience will agree --- a paradigm. The implication is that what is in dispute is "just like that."
   In Latin translations of Aristotle, paradeigma became exemplum , which pursued its own career in medieval and renaissance theories of argument. The word paradigm was, however, conserved in modern European languages but largely divorced from rhetoric. It tended to have very limited usage, for situations where a standard model was to be followed, or imitated. When schoolchildren had to learn Latin, they were told to conjugate to love ----"I love," you love," he/she/it loves"---amo, amas, amat, and so on. That was the paradigm, the model to imitate with similar verbs. The primary use of the word paradigm was in connection with grammar, but it was always available as a metaphor. As metaphor it never took off in English, but it seems to have been more common in German. In the 1930s members of the influential philosophy group the Vienna Circle, such as Moritz Schlick and Otto Neurath, were comfortably using the German word in their philosophical writings. 
  In the early-to-mid-1900s, some English analytic philosophers promoted the word. This was partly because the profoundly Viennese Ludwig Wittgenstein had made much use of it in his lectures at Cambridge University during the 1930s. His Cambridge classes were obsessively discussed by those who fell under his spell. The word appears several times in hisPhilosophical Investigations[ another great book , first published in 1953 ]. The first use of the word in that book speaks of a "paradigm of our grammar," although Wittgenstein's idea of grammar is far more encompassing than the usual one. Later he used it in connection with "language-games," an originally obscure German phrase which he made part of general culture.
   Kuhn probably first read Wittgenstein at Harvard and then at Berkeley, but he had many conversations with Stanley Cavell, a fascinatingly original thinker who was deeply immersed in Wittgenstein.  Each acknowledged the importance, at that moment in their lives, of sharing their intellectual attitudes and problems. And paradigm definitely came up as problematic in their discussions. 
   At the same time, some British philosophers invented a happily short-lived "paradigm-case argument," so named in about 1957. It was much discussed, for it seemed to be a new and general argument against various kinds of philosophical skepticism.  Here is a fair parody of the idea. You cannot claim we lack free will [for example], because we had to learn the use of the expression "free will" from examples, and they are the paradigms. Since we learned the expression from the paradigms, which exist, free will exists. 
   "Normal Science" is based on prior scientific achievements acknowledged by some scientific community. Paradigm entered the science vocabulary hand in hand with scientific community. The achievements served as exemplars of what to do, the kinds of questions to ask, successful applications, and "exemplary observations and experiments." 
   Kuhn became interested increasingly interested in events much smaller in scope than Newton, which pertained to small communities of workers. There are very large scientific communities --- genetics, or condensed-matter [solid-state] physics, for example. But within such communities, there are smaller and smaller groups, so that in the end the analysis should apply to "communities of perhaps a hundred members, sometimes significantly fewer." Each will have its own group of commitments, its own models of how to proceed. 
   Moreover, the achievements are not just anything notable. They are 
  [1] "sufficiently unprecedented to attract an enduring group of adherents" away from what has been going on. And 
[2] they are open-ended, with plenty of problems for the "redefined group of practitioners to resolve." 
   Kuhn concluded : "Achievements that share these two characteristics I shall henceforth refer to as 'paradigms'." 
   Accepted examples of scientific practice, including laws, theories, applications, experiment, and instrumentation, provide the models that create a coherent tradition and serve as the commitments which constitute a scientific community in the first place. The few sentences just quoted establish the fundamental idea of Kuhn's writing. Paradigms are integral to normal science, and normal science, practiced by a scientific community, continues as long as there is plenty to do, open problems which yield to research using methods acknowledged by the tradition. Normal science is characterized by a paradigm, which legitimates puzzles and problems on which the community works. All is well until the methods legitimated by the paradigm cannot cope with a cluster of anomalies. Crisis results and persists until a new achievement redirects research and serves as a new paradigm. That is a paradigm shift.