Updated: 21 January 2000

      “History, if viewed as a repository for more than anecdote or chronology, could produce a decisive transformation in the image of science by which we are now possessed.  That image has previously been drawn, even by scientists themselves, mainly from the study of finished scientific achievements as these are recorded in the classics and, more recently, in the textbooks from which each new scientific generation learns to practice its trade.   Inevitably, however, the aim of such books is persuasive and pedagogic; a concept of science drawn from them is no more likely to fit the enterprise that produced them than an image of a national culture drawn from a tourist brochure or a lanague text.  This essays attempts to show that we have been misled by them in fundamental ways.  Its aim is a sketch of the quite different concept of science that can emerge from the historical record of the research activity itself.”  Kuhn 1962




The Received Image


1.     Demarcation


2.     Scientific method - inductive algorithm


3.     Discovery vs justification


4.         Observation and theory


Foundationalism (“observation sentences”)


 theoretic terms


meaning via observational sentences

theories are deductive structures


5.     Science is cumulative      (somehow)


6.     Science about the world          (somehow)

            (instrumentalism, realism)


7.     Science is paradigm of rationality.

8. Unity of science : everything reduces to physics





Community with shared commitments


Paradigm : what the community is solid on.


      Metallurgy in Beijing and Oxford

      Philosophy in Paris and Oxford

      Sociology ....


      “What do its members share that accounts for the relative fullness of their professional communication and relatively unanimity of their professional judgement?”





1.     Shared symbolic generalisations.


2.     Models - pictures that guide research

            (plate tectonics, computer analogies)


3.     Values - good making features of theories







      enforcement mechanism ?





4.     Metaphysical principles

            untestible guiding assumptions

                  time not a causal factor

                  theories must be deterministic



5.     Exemplars:

      agreement on concrete problems

            and on good solutions




Paradigm as achievement - transmitted to new generation via textbooks etc

Paradigms - shared examples


No complete, enlightening verbal description.


      Must use examples.


      Scientist exercises judgement

            (like chicken sexers)



“I myself have introduced the term ‘paradigm’ to underscore the dependence of scientific research upon concrete examples that bridge what would otherwise be gaps in the specification of the content and application of scientific theories.” (Kuhn)





      Room for disagreement on relative importance of values and on interpretation of particular values (ie., simplicity)


      Circles vs. ellipses


A vague idea ?


      Masterman - 23 uses of “paradigm” !


      “paradigms of a mature science can be determined with ease”


Value ?


      directs attention to neglected aspect

      new vocabulary - try it and see


Social sciences are pre-paradigmatic





Normal Science


      paradigm dominant


      work inside solving problems it determines


      conservative - do more of the same thing


      basically puzzle solving


experiments test the experimenter, not the theory


undergraduates are not allowed to falsify theories - learn to get the “right” result.





      unsolved problems

      accumulate in time




anomalies > failure of consensus > revolution


      analogy with political revolutions


new theories do not triumph because of better evidence, triumph because of the failure of the old





      “no common measure”


paradigm defines its own standards, its own values [interpretation of the values]


      no rational choice


external explanation via sociological and psychological factors


“Already  it should be clear that the explanation [of scientific change] must, in the final analysis be psychological or sociological.  It must, that is, be a description of a value system, an ideology, together with an analysis of the institutions through which that system is transmitted and enforced.” (Kuhn)


      Cyril Burtt and IQ testing

      Communists and Lamarck


Kuhn ?



Strong Programme in the Sociology of Scientific Knowledge



David Bloor

Knowledge and Social Imagery



Barry Barnes


Scientific Knowledge and Sociological Theory


Interests and the Growth of Knowledge



JR Brown

The Rational and the Social




Extreme sociological approach


1.     Self-destructs 


      Why agree?

      Arguments or bribes?



2.     Mysterious


If all is determined sociologically, how come computers work?



3.     While do conflicts get resolved? Why do they not continue as in morals or art?


“Theories do not get refuted, old theoreticans die.” Planck



Kuhn :      deeply ambivalent


      loves science and scientific progress


      “First, the new candidate must seem to resolve some outstanding and generally recognised problem that can be met I no other way.  Second, the new paradigm must promise to preserve a relatively large part of the concrete problem-solving ability that has accrued to science through its predecessor.” 



      rhetoric of “scientific values” and “paradigm” takes him in the opposition direction.


      “values” justified as means to the end


      over-reaction to the absence of algorithms


Kuhn fails to see that according a role for judgement does not mean a failure of objectivity



The Ultimate Test



      “scientific values” at best guiding considerations


      ultimate test is predictive and manipulative power


      hard to give examples of sustained disagreement in science which can be explained by reference to differences as to the “values”


      eventually the game is over


Kuhn no progress in sense of truth or verisimilitude or finding “what is really there”, only via problem solving



Incommensurability       Part Two


radical meaning variance -

      different paradigms involve different languages -no theory neutral language in which to express the theories, so no rational choice


Source in positivism


Meaning of O-terms is unproblematic ???

Meaning of T-terms via role in theory

            not by verbal definitions

            not by ostention

So, theory change means change in meaning


No dichotomy between O and T

Therefore, meaning variance applies to all terms - both O and T.


So if Newton met Einstein, conversation couldn’t get off the ground.


Textbook derivations are invalid!






1.     Radical:   No rationality.

                        All is sociology.


2.     Confused: Kuhn

                        “partial communication”


3.     New non-holistic theory of meaning


      H Putnam

            “Explanation and Reference”

            “The Meaning of ‘Meaning’”

      in his Mind, Language and Reality


      W Newton-Smith

            Rationality of Science Ch 7




The Two Kuhns


      Temperate Kuhn


            sees deficiencies in positivists & Popper




            science - essential social component


            no algorithm of theory choice


            progress & rationality possible but





      Radical Kuhn


            carried away by innovative vocabulary

            over-reacts to his own discoveries


            no progress





Paradigms as changes in world view


      Just dramatic mode of expression ?


      [As if] ... “the community had been transported to another planet where familiar objects are given in a different light and are joined by unfamiliar ones as well”


      “... inhabit different worlds in a sense I am unable to explicate further...”


      Einstein did not just discovered curved space, he curved space!



KOT : Kuhn over the top.


No progress. World changes with theory change.






My goal is double. On the one hand, I aim to justify claims that science is cognitive, that its product is knowledge of nature, and that the criteria it uses in evaluating beliefs are in that sense epistemic. But on the other hand, I aim to deny all meaning to claims that successive scientific beliefs become more and more probable or better and better approximations to the truth and simultaneously to suggest that the subject of truth claims cannot be a relation between beliefs and a putatively mind-independent or “external” world.




What, if not a match with external reality, is the objective of scientific research? Though I think it requires additional thought and development, the answer supplied in Structure still seems to me the right one: whether or not individual practitioners are aware of it, they are trained to and rewarded for solving intricate puzzles – be they instrumental, theoretical, logical, or mathematical – at the interface between their phenomenal world and their community’s beliefs about it. That is what they are trained to do and what, to the extent they retain control of their time, they spend most of their professional lives doing. Its great fascination – which to outsiders often seems an obsession – is more than sufficient to make it an end in itself. For those engaged in it, no other goal is needed, though individuals often have a number of them. (Kuhn)




If that is the case, however, the rationality of the standard list of criteria for evaluating scientific belief is obvious. Accuracy, precision, scope, simplicity, fruitfulness, consistency, and so on, simply are the criteria which, puzzle solvers must weigh in deciding whether or not a given puzzle about the match between phenomena and belief has been solved. Except that they need not all be satisfied at once, they are the “defining” characteristics of the solved puzzle. It is for maximizing the precision with which, and the range within which, they apply that scientists are rewarded. To select a law or theory which exemplified them less fully than an existing competitor would be self-defeating, and self-defeating action is the surest index of irrationality. (Kuhn)