>I'd have to re-read the pieces of Kuhn in order to clear this up, and
>I sold the book years ago.
you are right chuck. Kuhn does examine a paradigm chaange as that which occurs in the transition to a "normal science", however, he also argues that a paradigm, itself, is what makes later paradigm change possible _within_ a field.
"If the historian traces the scientific knowledge of any selected group of related phenomena backward in time, he is likely to encounter some minor variant of a a pattern here illustrated from the history of physical optics. Today's physics textbooks tell the student that light is photons, i.e., quantum-mechanical entities that exhibit some characteristics of waves and some of particles. Research proceeds accordingly, or rather according to the more elaborate and mathematical characterization from which this usual verbalization is derived. That characterization of light is, however, scarcely half a century old. Before it was developed by Planck, Einstein, and others early in this century, physics texts taught that light was transverse wave motion, a conception rooted in a paradigm that derived ultimately from the optical writings of Young and Fresnel in the early nineteenth century. Nor was the wave theory the first to be embraced by almost all practitioners of optical science. During the 18th century the paradigm for this field was provided by Newton's Opticks, which taught that light was material corpuscles. At the time physicists sought evidence, as the early wave theorists had not, of the pressure exerted by light particles impinging on solid bodies.
these transformation of the paradigms of physical optics are scientific revolutions, and the successive transition from on paradigm to another via revolution is the usual developmental pattern of mature science. it is not, however, the pattern characteristic of the period before Newton's work, and that is the contrast that concerns us here. No period between remote antiquity and the end of the seventeenth century exhibited a single generally accepted view about the nature of light. Instead, there were a number of competing schools and sub-schools, most of them espousing one variant or another of epicurean, Aristotelian, or Platonic theory. One group took like to be particles emanating from material bodies; for another it was modification of the medium that intervened between the body and the eye; still another explained light in terms of an interaction of the medium with an emanation from the eye; and there were other combinations and modifications besides. Each of the corresponding schools derived strength from its relation to some particular metaphysic, and each emphasized, as paradigmatic observations, the particular cluster of optical phenomena that its own theory could o most to explain. Other observations were deal with by ad hoc elaborations, or the remained as outstanding problems for further research.
At various times all these schools made significant contributions to the body of concepts, phenomena, and techni2ques from which Newton drew the first nearly uniformly accepted paradigm for physical optics. any definition of the scientist that excludes at least the more creative members of these various schools will exclude their modern successors as well. Those men were scientists. yet anyone examining a survey of physical optics before newton may well conclude that, though the field's practitioners were scientists, the net result of their activity was something less than science. Being able to take no common body of belief for granted, each writer on psychical optic felt forced to build his field anew from its foundations. In doing so, his choice of supporting observation and experiment was relatively free, for there was no standard set of methods or of phenomena that every optical writer felt forced to employ and explain. Under these circumstance, the dialogue of the resulting books was often directed as much to the members of other schools as it was to nature. That pattern is not unfamiliar in a number of creative fields today, nor is it compatible with significant discovery and invention. it is not, however, the pattern of development that physical optics acquired after newton and the other natural sciences make familiar today.
The history of electrical research in the first have of the 18th c provides a more concrete and better known examples of the way a science develops before it acquires its firs universally received paradigm. during that period there were almost as many views about the nature of electricity as there were important electrical experimenters, men like Hauksbee, Gray, Desguliers, Du Fay, Nollett, Watson, Franklin, and others. All their numerous concepts of electricity had something in common--they wer partially derived from one or another version of the mechanic-corpuscular philosophy that guided all scientific research of the day,. In addition, all were components of real scientific theories, of theories that had been drawn in part from experiment and observation and that partially determined the choice and interpretation of additional problems undertaken in research. Yet though all the experiments were electrical and though most of the experimenter read each other's works, their theory had no more than a family resemblance. <...> What the fluid theory of electricity did for the subgroup that held it, the Franklinian paradigm later did for the entire group of electricians. It suggested which experiments would be worthy of performing and which..would not. Only the paradigm did the job far more effe3citvely, partially because the end of the inter-school debated ended the constant reiteration of fundamentals and partly because the confidence that they were on the right track encouraged scientists to undertake more precise, esoteric, and consuming sorts of work. Freed from the concern with any and all electrical phenomena, the united group of electricians could pursue selected phenomena in far more detail, designing much special equipment for the task and employing it more stubbornly and systematically than electricians had ever done before. <...>
We shall be examining the nature of this highly directed or paradigm-based research in the next section, but must fir not how the emergence of a paradigm effects the structure of the group that practices the field. When, in the development of of a natural science, an individual or group first produces a synthesis able to attract most of the next generation's practitioners the older schools gradually disappear. In part their disappearance is cased by their members' conversion to the new paradigm. but there are always some men who cling to one or another of the older views, and they are simply read out of the profession, which thereafter ignores their work. The new paradigm implies a new and more rigid definition of the field.
<...> In the development of any science, the first received paradigm is usually felt to account quite successfully for most of the observation and experiments easily accessible to that science's practitioners. Further development, ordinarily calls for the construction of elaborate equipment, the development of an esoteric vocabulary and skills, and a refinement of concepts that increasingly lessens their resemblance to their usual common sense prototypes. That professionalization leads, on the one hand, to an immense restriction of the scientist's vision and to a considerable resistance to paradigm change. The science has become increasingly rigid. On the other hand, within those areas to which the paradigm directs the attention of the group,, normal science leads to a detail of information and to a precision of the observation-theory-match that could be science in no other way. Furthermore, that detail and precision of match have a value that transcends their not always very high intrinsic interest. Without the special apparatus that is constructed mainly for anticipated functions, the results that lead ultimately to novelty ordinarily do not occur. And even when the apparatus exists, novelty ordinarily emerges only for the man who, knowing with precision what he should expect, is able to recognize that something has gone wrong. Anomaly appears only against the back ground proved by the paradigm. The more precise and far reaching that paradigm is, the more sensitive an indicator it provides of anomaly hence of an occasion for paradigm change. <...>
He later goes on to ask the question, in the chapt The Response to Crisis, "For what is it that differentiates normal science from science in a crisis state? Not, surely, that the former confronts no counterinstances. On the contrary, what we previously called the puzzles that constitute normal science exist only because no paradigm that provides a basis for research ever completely resolves all its problems. The very view that have ever seemed to do so (e.g., geometric optics) have shortly ceased to yield research problems at all and have instead become tools for engineering. Excepting those that are exclusively instrumental, every problem that normal science sees as a puzzle can be seen, from another viewpoint, as a counterinstance and thus as a source of crisis.
<...>
During the transition period there will be a large but never complete overlap between the problems that can be solved by the old and by the new paradigm. But there will also be a decisive difference in the modes of solution. when the transition is complete, the profession will have changes its view of the field, its classic cases of a science's reorientation by a paradigm change.
Thomas Kuhn, The Structure of Scientific Revolutions, Second Edition pp 11-20 (The Route to Normal Science) and pp. 63-65 (Anomaly and the Emergence of Scientific Discoveries), and pp 79 85 (Response to Crisis)