A Historical Introduction to the
Philosophy of Science

The following is a summary of the fourteenth chapter of John Losee's book, A Historical Introduction to the Philosophy of Science (fourth edition), with some ancillary notes.

Philosophers discussed in this chapter: Thomas Kuhn (1922–96); Imre Lakatos (1922–74); Larry Laudan (1941—)

Kuhn on "Normal Science" and "Revolutionary Science"

(p. 197) Philosophers of science came to accept that the logical reconstructionist reduction of scientific practice to exercises in formal logic did not capture what actual scientists do.

(p. 198) Kuhn built on the work of Toulmin and Hanson to reconstruct the history of science as distinct periods where a period of 'normal science' is punctuated by 'revolutionary science' in which an earlier 'paradigm' is replaced ([1962] The Structure of Scientific Revolutions).

For Kuhn, most science is carried out as puzzle solving 'normal science' in which scientists:

1. close the measurement gap between observations and the paradigm's predictions
2. extend the scope of the paradigm to other phenomena
3. determine the values of universal constants
4. formulate quantitative laws that explain the paradigm
5. work out how to apply the paradigm to new areas of interest

A competing paradigm arises when the dominant paradigm faces unsolved anomalies. The revolution against a dominant paradigm is sudden and unplanned, like a Gestalt switch.

(p. 199) Kuhn rejected the logic of falsification as there are three terms in the rejection of a paradigm:

1. established paradigm
2. rival paradigm
3. observational evidence

But for Kuhn, competing paradigms are not measured against the same observation statement as there is no paradigm-independent observation language. Conceptual differences mean common terms have different meanings (e.g., 'space', 'time', and 'matter' mean different things in General Relativity compared with Newtonian physics).

Scheffler objected that Kuhn made revolutions in science subjective.

(p. 200) For Scheffler, although competing paradigms have different methods of classification, they both refer to the same objects in the real world. Genuine progress in science happens because the new paradigm better describes those same objects.

For Scheffler, Kuhn failed to distinguish between 'seeing x' and 'seeing x-as-something-or other'.

[LA: For example, while you see the gestalt drawing as a duck and I see it as a rabbit, we are still both seeing the same object.]

Scheffler instanced how Special Relativity Theory replaced Newtonian Mechanics even though the 'mass' of each electron within a synchrotron is defined differently in each paradigm. Never the less, both paradigms refer to the same objects in the synchrotron.

Kuhn insisted on a rational standard for paradigm-replacement that included:

1. constructive accommodation of crisis-inducing anomalies
2. increase in quantitative precision of measurement

(pp. 200–1) Shapere and Buchdahl also criticized Kuhn for equivocating between two meanings of 'paradigm':

1. broad sense – 'disciplinary matrix' as a constellation of shared beliefs, values, techniques
2. narrow sense – 'exemplar' as particular presentation of a theory

(p. 201) If Kuhn means 'paradigm' in the narrow sense, then the distinction between normal science and revolutionary science is greatly diminished. If he means it in the broad sense, then it is too vague to be useful to historians of science.

In his 1962 Postscript, Kuhn conceded he equivocated, but maintained that historians of science will find both kinds of 'paradigm'; both exemplars and disciplinary matrices.

In expecting historians to reveal a large number of relatively small groups of researchers (micro-communities), Kuhn made a number of concessions:

1. revolutions may happen within a micro-community without causing a broader revolution
2. one paradigm may replace another within a micro-community without a prior crisis
3. a crisis can be diverted by scientists by shelving the anomaly till a later time
4. periods of 'normal science' within a micro-community may include debate over fundamental metaphysical commitments

With these concessions, Losee thinks Kuhn has blurred his previously sharp distinction between normal science and revolutionary science.

(p. 202) In disarming his critics with his Postscript, Kuhn's thesis is no longer radical or objectionable. Kuhn's 'normal science' is no longer the dogmatic and monolithic enterprise he originally depicted it as.

Lakatos on Scientific Research Programmes

Lakatos agreed with Kuhn on the continuity of science: science progresses in an 'ocean of anomalies' (e.g., anomalous motion of Mercury).

Lakatos criticised Popper's falsificationism for not distinguishing between refutation and rejection. Popper responded that rejection depends on availability of alternative theories.

(p. 203) Lakatos unfairly criticised Kuhn for thinking that revolutions in science are like an irrational 'mystical conversion'.

Lakatos, like Popper, sought to write a rational reconstruction of the history of science. For Popper, the unit of theory appraisal is the individual theory. For Lakatos, it is a 'research programme' extending over a period of time with modifications along the way (see diagram).

For Lakatos, a 'research programme' consists of:

• negative heuristic – 'hard core' that resists falsification by methodological fiat (convention)
• positive heuristic – strategy for directing research to overcome anomalies (p. 204)

(p. 204) The positive heuristic builds a 'protective belt' of auxiliary hypotheses around the non-falsifiable hard core of the programme (e.g., Newtonian Research Programme adjustments to solve anomalies with planetary and lunar orbits).

For Lakatos, a negative test does not refute an entire research programme (contra Popper), but directs attention to modifying the set of auxiliary hypotheses.

Contra Duhem and Kuhn, Lakatos argued that a research programme as a series of theories can be appraised objectively as either a 'progressive problem-shift' or a 'degenerating problem-shift'.

(p. 205) A series of theories within a research programme is a 'progressive problem-shift' when the later theory:

1. accounts for the success of the earlier theory
2. has more empirical content than the earlier theory
3. has some of its excess empirical content corroborated by experiment

For criterion 1., the asymptotic agreement of calculations with the earlier theory counts as an instance of accounting for the successes of the earlier theory (e.g., Ideal Gas Theory, Bohr Theory of the Hydrogen Atom).

A problem for Lakatos' objective appraisal criteria is that a currently degenerating research programme may, with more research, stage a comeback to become progressive (e.g., Prout's programme on atomic weights).

(p. 206) Feyerabend objected that for Lakatos' criteria to be of practical guidance for scientists for when to abandon a degenerating research programme, they require a time limit for application.

Lakatos responded that Feyerabend ignored the distinction between:

1. appraising a research programme according to methodological criteria
2. deciding whether to continue working on a research programme

Because an appraisal may change over time, Lakatos insisted that it is not the role of the philosopher of science to recommend to scientists which programmes to work on.

For Lakatos, while a scientist may rationally choose to work on a degenerating research programme, they must recognize the risk they are taking on by doing so. Lakatos advocated a public register of the successes and failures of each research programme.

Laudan on Problem-Solving

In Laudan's [1977] Progress and Its Problems, he saw the unit of progress in science as the solved problem. Problems in science are of two types:

1. empirical problems – about the structure or relations of objects within the discipline
2. conceptual problems – about incompatibilities between theories and incongruities between a theory and methodological presuppositions

An example of a conceptual problem was the incongruity between Newton's axiomatization of mechanics and his insistence on the inductive method.

(p. 207) For Laudan, this conceptual problem solving allows for evolving standards of rationality (in Newton's case, from an induction by simple enumeration standard to a hypothetico-deductive standard).

The logicist view is that progress in science is judged against a fixed standard of rationality. Laudan inverted that process by showing how progress in problem-solving in science modifies the standard of rationality.

For Laudan, progress in science is achieved by:

1. increasing the number of solved empirical problems (even where the solution is only approximate)
2. resolving anomalies (including anomalies where a theory fails to explain an observation that a rival theory explains)
3. resolving conceptual conflicts among theories

Laudan explained how anomalies can be removed by:

1. revising an anomalous observation statement
2. adding an auxiliary hypothesis
3. revising the theory

Questions to Consider:

1. Was Scheffler right in criticising Kuhn for not recognizing that competing paradigms still refer to the same objects?
2. How successful was Kuhn in defending a sharp distinction between 'normal science' and 'revolutionary science'?
3. What do you understand by the 'rational reconstruction of science'?
4. Is Lakatos' methodology of scientific research programs an improvement on Popper's falsificationism?
5. Did Lakatos successfully defend his objective criteria of research programme appraisal against Feyerabend's objection?
6. Is Laudan right in thinking that progress in science modifies our standards of rationality?
7. What other examples can you think of where solving a problem in science has improved scientists methodological principles of reasoning?

Copyright © 2022–3 Leslie Allan