I. Background

 

Thomas Kuhn (1922-96) was a physicist, then a historian of science, then a philosopher of science. Most well-known book, The Structure of Scientific Revolutions, has been described as “the most influential on the philosophy of science” in the 20^th century, and as “one of the most cited academic books of all time.” Published in 1962, millions sold, translated into 19 languages, but no movie with Harrison Ford.

 

One key idea is that of a “paradigm”. It has been picked up and used (and abused) in many disciplines. Google - 782,000 hits on “kuhn, paradigm”.

 

His main ideas can be interpreted in more radical and less radical ways. The more radical ones have attracted lots of people, especially in the humanities (though perhaps more in areas other than philosophy - hard to assess this). Some say he is responsible for the development of whole fields of study.

 

It may be that there is a political element to reactions to his work. One commentator writes: “Kuhn also maintained that, contrary to popular conception, typical scientists are not objective and independent thinkers. Rather, they are conservative individuals who accept what they have been taught and apply their knowledge to solving the problems that their theories dictate. Most are, in essence, puzzle-solvers who aim to discover what they already know in advance - "The man who is striving to solve a problem defined by existing knowledge and technique is not just looking around. He knows what he wants to achieve, and he designs his instruments and directs his thoughts accordingly." - some people will be attracted to this, some won’t.

 

A key idea to latch onto is a distinction between historical and ahistorical approaches to the study of science, especially to the questions about rationality and method that most interest philosophers. A lot of what we have done has been the latter. Kuhn emphasized the latter, but in connection with the sorts of questions that the former addressed.

 

No detailed study of Kuhn’s views here. Just some main themes and issues.

 

II. Some Main Claims

 

Kuhn is sometimes taken to have said that science is not a rational enterprise, that it does not make progress, that it does not get closer to the truth. Some of what he wrote may invite this. But he also seemed to tone it down (or clarify it) in later writings.

 

One important theme in Kuhn’s work has to do with how science develops. Main stages: immature science, normal science, revolutionary science. Rather than steady gradual development, with possibly major discoveries along the way, there are revolutions. Normal science moves along pretty much the way the traditional picture says: experimental results enable scientists to modify theories slightly, to get more precise measurements about the relationships between variables, figure out how to deal with results that didn’t quite fit, and so on. He said that within this period, scientists were working within a “paradigm”. These seemed to include key examples (as described in textbooks) that illustrated the central ideas and they were used to show how to work within the field. But they also included more general commitments to views about how the world works, how science works, what the goals of science are. Normal science engages in “solving puzzles”. (This seems like a put down. Intended?) He also seemed to allow that there is a kind of objectivity to this - there are agreed upon rules for proceeding, and you apply them.

 

The second key term associated with Kuhn (other than “paradigm”) is “revolution”. They are related: a revolution is a paradigm shift. This is a wholesale change, not a mere replacement of one theory by another. There are large scale shifts in beliefs, values, commitments. Relatively sudden. And, what may be most exciting to some, there is some non-rational character to such shifts. There isn’t some objectively assessible argument that leads to revolutions. It’s a sociological, not a rational, phenomenon. “As in political revolutions, so in paradigm choice – there is no standard higher than the assent of the relevant community.” Like all analogies, this one can be abused. But consider ordinary political change, with modification of laws, changes in leaders, etc. Some of these may even be significant. And then sudden changes such as replacing a king by with a democratically elected government.

 

III. Arguments

 

There are several lines of thought in Kuhn that lead to his conclusions. Here are some of them, none spelled out in detail. Some will be familiar.

 

1) Observation is theory laden. Recall example about sun from earlier in the semester. Some people see the sun moving, some see it at rest. If you think that this sort of thing is pervasive, then the conclusion seems to be that there is no neutral grounds on which to assess different theories (or radically different theories). People in different paradigms will make “different” observations.

 

2) Terms don’t have the same meanings across paradigms. What you mean by a word depends upon the larger theory that it is part of. Maybe this is an example: “planet” means in current theory something like “satellite of the sun”. Maybe in an older theory it meant in part “satellite of the earth”. But then proponents of the different views aren’t even arguing with one another when one says and the other denies “Planets go around the earth”. [Sense/reference issues make this hard to think about clearly.]

 

3) Shifting standards. Cf. our discussion last week. Suppose you agree on the criteria for selecting theories, as we discussed last week. But one group weighs scope very heavily and another weighs simplicity very heavily. There seems to be an argument based on the idea that there is no right way to figure out the proper weights, no way to resolve these disagreements.

 

4) Varying interpretations of individual standards. What is simplicity? Fewer objects, fewer basic principles, easier to understand? Ptolemy v. Copernicus.

 

IV. Brief Comments

 

1) One theme in here seems to be relativism. Kuhn seems to be saying that one aspect of a paradigm is the set of standards employed in rationally choosing theories and beliefs. One author characterizes it this way:

 

R: Any knowledge-claim P about field X can be evaluated only according to a particular set of background principles and standards; but there are rival sets of standards, and there is no way of choosing between incompatible sets of background principles and standards in evaluating P which does not beg the question in favor of the standards of evaluation chosen and against the ones rejected.

 

Global (universal) v. local versions of this. Unclear just which version he was accepting. Global version has this oddity: apply it to itself.

 

2) There is another aspect to the relativism that sometimes seems to emerge in Kuhn: there is no theory neutral truth. Rather, there is just truth within paradigms. [Again, interpreting him is hard.] The example about the sunrise from earlier in the semester again illustrates the idea. But, as we saw then, there may well be neutral ways to describe it. Both observers see a bright object in the sky whose position relative to the horizon changes.

 

3) Normal science/revolutions: some have argued that the history of science just does not reveal such dramatic variation. They say that there just is no clear distinction between normal science and revolutionary science. One aspect of this would require careful historical analysis: is it really true that there are major differences in the criteria of evaluation that accompany the major changes in theories accepted? Take an example in which there is supposed to be a paradigm shift. Is there really a change in principles? No one is denying that there are some changes that are more dramatic than others.

 

4) The idea that there is no basis for adjudicating disputes about standards is in need of further analysis and defense. Separate sociological/psychological questions from epistemic. Maybe some people will be unwilling to give up their theories. But it is not so clear that there are different underlying principles that prevent effective arguments that show that one side should abandon its view.