A PHILOSOPHICAL ANALYSIS OF THE INCOMMENSURABILITY THESIS IN

THOMAS KUHN’S THEORY OF SCIENCE

BY

UKASOANYA STANLEY IKECHUKWU

(DI/485)

BEING A LONG ESSAY SUBMITTED TO THE DEPARTMENT OF PHILOSOPHY,

DOMINICAN INSTITUTE IBADAN, IN AFFLIATION WITH UNIVERSITY OF

IBADAN, IBADAN; IN PARTIAL FULFILLMENT OF THE REQUIREMENTS FOR

THE AWARD OF BACHELOR OF ARTS DEGREE IN PHILOSOPHY

IBADAN

JUNE 2014

CERTIFICATION

This is to certify that this long essay titled “A PHILOSOPHICAL

ANALYSIS OF THE INCOMMENSURABILITY THESIS IN THOMAS KUHN’S THEORY

OF SCIENCE”, was carried out by Ukasoanya Stanley Ikechukwu, in

the department of philosophy, Dominican Institute of Philosophy

and Theology, Samonda, Ibadan, Nigeria.

Date …………………. Sign……………………………..

MODERATOR

DR. ISAAC UKPOKOLO

Department of Philosophy,

University of Ibadan,

Ibadan, Nigeria.

DEDICATION

To the Triune God from whence comes my existence and to my

parents, Mr. Patrick Ukasoanya and Mrs. Mary Ukasoanya.

ACKNOWLEDGEMENT

I sincerely express my profound appreciation and gratitude to God

who bestowed on me the wisdom, knowledge, understanding and

strength and through whom I have been able to carry out this

work. I also thank the Mother Thrice Admirable, Queen and

Victress of Schoenstatt for her continuous intercession.

I express my gratitude to my parents Mr and Mrs Patrick

Ukasoanya, their love and encouragement has always spurred me on.

To my siblings Charles, Kelechi and Amarachi, your unwavering

support was never lacking. I give special thanks to my cousin Fr.

Solomon Emegharibe, your unalloyed support and words of

encouragement have always been a source of motivation. To you all

I am greatly indebted.

I thank most specially my moderator Dr. Isaac Ukpokolo who

accepted and made out time out of his tight schedule to moderate

and guide me in accomplishing this work. I am indeed very

grateful.

I wish to give my sincere gratitude to the Secular institute of

Schoenstatt Fathers’ for the love and support shown to me

throughout these of years of study. I thank Frs. Alfred Kistler,

Andres Rodriguez, Claudius Uwaoma, Reginald Ibe, Klaus Desch,

Juan Pablo Cattogio, Paul Nwachukwu and Magnus Ifedikwa.

I cannot forget my brothers with whom I began this academic

adventure, Matthias, Emma Ibn Okeke, Franchesco, Henry Philips,

Johnpaul, Sylvester, Eustacio and Cyriacus, your presence and

support was never lacking. I thank you. To my other brothers: Oga

Pat Ogbonna, Edo, Nanks (Stanley), Remije, Henry dike, John, Dan,

Felixo, Collins, Barna, Gudof (Pat Ugwoke), Dansuma, Jude, Emma

Iwu, Mozie, Lawrence, Obut, Cyprain, Jose Maria, Paulinus,

Fortune, Livinus, Oche, Paschal, Sheddy, Ben and Ben. I thank you

all.

I thank in a very special way, Patrick Ugwoke, Collins and John

who helped in proofreading this work and offered me a share in

their philosophical insight. I am very grateful.

To all those who have contributed in one way or another to the

success of this essay and to those whose names cannot be

mentioned here, I thank you all and God bless you.

Ukasoanya Stanley Ikechukwu

TABLE OF CONTENT

TITLE PAGE

CERTIFICATION…………………………………………………………...ii

DEDICATION…………………………………………………………….....iii

ACKNOWLEDGEMENTS………………………………………………....iv

TABLEOFCONTENT...………………………………………………….....vi

INTRODUCTION.…………………………………………………………....1

CHAPTER ONE

THEORY OF SCIENCE……………………………………………………..3

1.1 The Common View of Science…………………………………………….31.2 Logical Positivism………………………………………………………….41.3 Normal Science…………………………………………………………….8

CHAPTER TWO

KUHN’S REVOLUTIONARY SCIENCE…………………………….…..17

2.1 Nature of a Paradigm……………..……………………………………....17

2.2 Senses of a Paradigm……………..……………………………………....20

2.3 Scientific Revolution………………..…………………………………....22

CHAPTER THREE

INCOMMENSURABLITY…………………………………………….…..33

3.1What isIncommensurability?......................................................................33

3.2 Types of Incommensurability…………………………………………….36

3.2.1 Methodological Incommensurability…………………………...36

3.2.2 Observational Incommensurability……………………………..40

3.2.3 Early Semantic Incommensurability…………………...……….42

3.2.4 Later Semantic Incommensurability…………………………....43

CHAPTER FOUR

EVALUATION AND CONCLUSION……...………………………….…47

4.1Criticisms of Kuhn’s Theory…………………………………………..….47

4.2Influence of Thomas Kuhn to Philosophy of Science…….……………....60

4.3Conclusion………………………………………………………………...62

BIBLIOGRAPHY…………………………………………………………..65

Introduction

Philosophers have sought since the onset of the philosophy of

science to develop a method, an objective method through which

scientific investigations are carried out. However, none so far

has developed one without anomalies hitting at the very

foundations of these methods. Thomas Kuhn, a physicist who turned

his attention to the history of science made a commendable

attempt in his book The Structure of Scientific Revolution to create a

method in correlation with the history of science. The book

begins with his famous statement “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”.1

He aimed at a philosophical view of the History of Science. In it

he held that science enjoys periods of stable growth punctuated

by revisionary revolutions. He further held that theories which

emanates from differing periods suffer certain kinds of failure

of comparability and thus he produced his incommensurability

thesis. He tried to explain that in the process of paradigm shift

a theory is overridden by a new theory which is incomparable with

it. Furthermore, reason as a prerequisite for theory choice was

denied by Kuhn. Instead he opted for a psychological basis to

explain his account of theory choice. However, the

incommensurability thesis would fetch Kuhn more enemies than

friends in the world of philosophy of science and he would spend

a great deal of his time explaining and re-evaluating his

incommensurability thesis.

1 Thomas S. Kuhn, The Structure of Scientific Revolutions (Chicago: University of ChicagoPress, 1970), p.1

This work is divided into four chapters. In the first we shall

look at the theory of science which will contain the

commonsensical view of science as well as the doctrines of

logical positivism. Finally in that chapter we shall look into

Kuhn’s account of normal science.

The second chapter shall be based on Kuhn’s revolutionary

science. Here we see the origin and nature of Kuhn’s idea of

paradigms and the variety of senses in which he employs the term.

Then still in this chapter we shall look at Kuhn’s scientific

revolutions. Here we shall discuss Kuhn’s treatment of anomalies,

crisis, response to crisis and revolutions.

A scientific revolution involves the abandonment of one paradigm

and the embracement of another. The idea that one paradigm cannot

be compared with another is what will occupy us in this chapter.

Here we shall discuss Kuhn’s sources of incommensurability which

also supply us with the types of incommensurability encountered

in Kuhn’s account of science.

In the fourth and final chapter, we shall make and evaluation of

Kuhn’s account of science as discussed in the preceding chapters.

This evaluation shall comprise a retrieval of the arguments

brought against Kuhn’s account of science and also an assessment

of the influences which Kuhn has had in philosophy of science.

CHAPTER ONE

THEORY OF SCIENCE

1.1 The Common View of Science

Scientific activity involves the use of certain scientific

methods to conclusively confirm or conclusively falsify various

theories. Theories are derived from observations which have been

experimented. The goal of science is to obtain knowledge of the

natural world. According to A.F Chalmers, “science is based on

facts; these facts are presumed to be claims about the world that

can be directly established by a careful, unprejudiced use of the

senses”.2 Science is thus a “structure built upon facts”.3

This popular notion or rather commonsensical view of modern

science takes its origin from the revolutionary efforts of

scientists such as Galileo. Prior to the seventeenth century, the

foundation or basis of science was not taken to be observable

facts, rather, science was founded on authority, the “authority

of Aristotle and the authority of the bible”.4 Both of these

authorities were taken at that time as the bases on which

scientific knowledge is derived. However, with the challenge

which scientists such as Galileo, who rather than appealing to

authority appealed to sense experience, posed to these

authorities, there was a shift on the bases of science. This

rebellious attitude fortunately gave birth to modern science

which from then on took the bases of science to be facts of

experience.

1.2 Logical Positivism

2 A.F. Chalmers, What is this Thing called Science (Cambridge: Hackett PublishingCompany, Inc. 1999), p. 1.3 Ibid.4 Ibid., p. 2.

The logical positivists were disciples of the methods of science

and mathematics; they were disposed to reject metaphysics as did

the earlier positivists who considered metaphysics, the same way

as Comte did earlier, as been outdated by science. Now they have

an additional argument, that metaphysics is impossible as shown

by the logical and essential character of language. But to

differentiate themselves from the earlier Comtean positivists and

to emphasize that they would combine the rigorous techniques of

the new logic with the empirical temper of David Hume, they

called themselves ‘Logical positivists, or sometimes ‘Logical

empiricists’.5 They elaborated upon the view that philosophy is

not a theory but an activity. They held that philosophy does not

produce propositions that are true or false; it merely clarifies

the meaning of statements, showing some to be scientific, some to

be mathematical, and some including most so-called “philosophical

statements” to be nonsensical.6 Characteristics of logical

positivism are doctrines such as the rejection of metaphysics and

5 Samuel E. Stumpf, Philosophy History and Problems (New York: McGraw-Hill, 1971),p. 4536 Richard A. Popkin, Philosophy Made Simple (NewYork : Heinemann professionalPublishers Ltd, 1981), p. 291.

theology; the emotive theory of moral judgement, the

verifiability theory of meaning; the unity of science; and the

claim that legitimate philosophy consists solely of logical

analysis”.7

The classic position of the logical positivist is the call for

the outright rejection of metaphysics, ethics and religion. This

position is contained in the Vienna Circle’s verification

principle. “The logical positivists, like Hume, claimed that all

legitimate uses of language were either synthetic and a posteriori,

that is, empirical, or were tautologies”.8 For the logical

positivists, the empirical propositions were those of the natural

sciences, which were understood to include the factual statements

of everyday life. “The tautologies are typically what we meet in

the exact sciences such as mathematics”.9 For the logical

positivists, the cognitive meaning of a sentence is its method of

verification. “If a sentence is not verifiable or is not a truth-

7 I. Ukpokolo, “Philosophy of Science: Nature and Programme” In Issues andProblems in Philosophy, edited by K. A Olu-Owolabi (Ibadan: Grovacs Network, 2007). p. 209.8 J. O. Urmson, Philosophical Analyses: its Development between the two World Wars (London:Oxford University Press, 1976). p.116.9 Ibid.

value tautology then it is cognitively meaningless. Logic,

mathematics, and the physical sciences are regarded as

legitimate, because they satisfy the verifiability criterion”.10

Rudolf Carnap states that there are direct and indirect

verification and both are central to the scientific method, “for

in the field of science, every proposition asserts something

about either the present perceptions or future perceptions. In

both cases, verification is either through direct perception or

by the logical connection of already verified propositions”.11

On the application of the verifiability criterion to metaphysics,

the logical positivists argue that metaphysics cannot be

subjected to empirical scrutiny and as such is meaningless.

Metaphysics is said to be concerned with the truth about the

nature of things and it often makes assertions such as ‘the

future resembles the past’ ‘space and time are absolute’. Science

thus would be based on metaphysical claims that could not be

subjected to empirical verification. This was rejected by the

positivists, “a pure scientific theory, they maintained, should

10 I. Ukpokolo, “Philosophy of Science: Nature and Programme” loc.cit.11 S.E. Stumpf, Philosophy: History and Problems op.cit., p. 454.

be an algorithm for the codification of experiences”.12 According

to Carnap, metaphysical propositions are not verifiable, or, if

an attempt at verification is made, the results are always

negative. He says that metaphysicians cannot avoid making their

propositions nonverifiable because if they make them verifiable

they would belong to the realm of empirical science since their

truth or falsehood would depend upon experience”.13 Thus he

rejects, out right, metaphysics, he says:

Metaphysical propositions are neither true nor false, because theyassert nothing, they contain neither knowledge nor error, they liecompletely outside the field of knowledge, of theory, outside thediscussion of truth or falsehood. But they are, like laughing,lyrics, and music, expressive. They express not so much temporaryfeelings as permanent emotions or volitional dispositions.... Thedanger lies in the deceptive character of metaphysics; it gives theillusion of knowledge without actually giving any knowledge. This isthe reason why we reject it.14

The logical positivists hold that scientific knowledge begins

from observations. These are then reported in observation

statements which in turn forms the basis of scientific theories.

Observation statements, for the positivists are singular

12 I. Ukpokolo, “Philosophy of Science: Nature and Programme” loc.cit.13 S.E. Stumpf, Philosophy: History and Problems loc.cit.14 R. Carnap, Philosophy and Logical Syntax (London: Kegan Paul, Trench, Trubner &Co. Ltd., 1935). p. 37.

statements, however, the theories which they form are expressed

in the form of universal statements.

The question then is how to logically justify the proclamation of

universal statements form a limited number of observation

statements. To this the positivists recommends an inductive

process. Thus a limited number of statements would produce a

legitimate generalisation but this will only happen under some

conditions. First, the number of observation statements must be

large. Secondly the observations must be repeated under a wide

variety of conditions. Thirdly, no one observation statement

should be found to be in conflict with the derived universal law.

“To this extent, science as a rational inquiry for the logical

positivist is based on the principle of induction. As it is put,

the body of scientific knowledge is built by induction from the

secure basis provided by observation”.15

Furthermore, the positivists argue that science is cumulative. In

other words, scientists have as their foundation achievements of15 A.F. Chalmers, What is this Thing called Science (Cambridge: Hackett PublishingCompany, Inc. 1999), quoted in I. Ukpokolo, “Philosophy of Science: Nature andProgramme” In Issues and Problems in Philosophy, edited by K. A Olu-Owolabi (Ibadan: Grovacs Network,2007). p. 211.

their predecessors, and “the progress of science is a steady

growth in our knowledge of the world”.16 This feature of science

is sharply contrasted with other activities, such as art,

literature and philosophy, which are progressive in a much looser

and controversial sense. Also, they claim that science is unified

in the sense that there is a single set of fundamental method for

all the sciences, and in the sense that the natural sciences at

least are all ultimately reducible to physics.

More so, it is claimed that there is an “epistemologically

crucial distinction between the context of discovery and the

context of justification”.17 The proof for scientific knowledge

ought to be evaluated without reference to the causal origins of

the theories or observations in question. In other words,

inquiries into who made some particular observations, and when a

theory was proposed and by whom for whatever reason, are not

necessary neither are they relevant to the question of the extent

to which the observations provide evidence for the theory. They

claim that there is an underlying logic of confirmation or

16 James Ladyman, Understanding Philosophy of Science (London: Routledge Publications,2002), p. 95.17 Ibid.

falsification implicit in all scientific evaluations of the

evidence for some hypothesis. Such evaluations are value-free in

the sense of being independent of the personal non-scientific

views and allegiances of scientists.

Furthermore, there is a sharp dichotomy between scientific

theories and other kinds of belief systems, as well as a sharp

distinction between observational terms and theoretical terms,

and also between theoretical statements and those that describe

the results of experiments. Observation and experiment is a

neutral foundation for scientific knowledge, or at least for the

testing of scientific theories. It is also agreed that scientific

terms have fixed and precise meanings.

1.3 Normal Science

Thomas Kuhn in his book The Structure of Scientific Revolutions challenged

the inductivist and falsificationist accounts of science. His

views have reverberated in the philosophy of science ever since.

Kuhn started his academic career as a physicist and then turned

his attention to the history of science. On doing so, he found

that his preconceptions about the nature of science were

shattered. He came to believe that traditional accounts of

science, whether inductivist or falsificationist do not bear

comparison with historical evidence.18

“Kuhn reports that his intellectually formative experience,

however, was inspired by his reading Aristotle’s Physics”.19 This

reading Kuhn refers to as his “Aristotle experience”. Kuhn

reports that he approached Aristotle’s texts with the Newtonian

mechanics in mind, and that his purpose was to answer the

question of how much mechanics Aristotle had known and the extent

of what he had left for upcoming scientists like Galileo and

Newton to discover. He states that having brought to the texts

the question formulated in that manner, he observed that

Aristotle had almost no knowledge of mechanics at all, and that

everything was left for posterity to discover. Precisely on the

topic of motion, Aristotle’s writings seemed to be full of

errors, both of logic and of observation. Kuhn reports that this

conclusion was disturbing for him, since Aristotle had been

18 A.F. Chalmers, What is this Thing called Science op.cit.,, p. 107.19 Thomas J. Hickey (2005), “Thomas Kuhn on Revolution and Paul Feyerabend onAnarchy” History of Twentieth Century Philosophy of Science, http://www.philsci.com (14 Nov. 2010), p. 6.

admired as a great logician and was an intelligent naturalistic

observer.

Kuhn then asked himself whether or not the fault was his rather

than Aristotle’s, because Aristotle’s words had not meant to

Aristotle and his contemporaries what they mean today to Kuhn and

his contemporaries. Kuhn describes his reconsideration of

Aristotle’s Physics: He reports that he continued to puzzle over

the text while he was sitting at his desk gazing abstractly out

the window of his room with the text of Aristotle’s Physics open

before him, when suddenly the fragments in his head sorted

themselves out in a new way and fell into place together to

present Aristotle as a very good physicist but of a sort that

Kuhn had never dreamed possible. Statements that had previously

seemed egregious mistakes afterward seemed at worst near misses

within a powerful and generally successful tradition. Kuhn then

inverts the historical order; his account of scientific

revolution describes what Aristotelian natural philosophers

required to reach Newtonian ideas instead of what he, a Newtonian

reading Aristotle’s text, required to reach those of the

Aristotelian natural philosophers. Thus he maintains that

experiences like his Aristotle experience, in which the pieces

suddenly sort themselves out and coming together in a new way, is

the first general characteristic of revolutionary change in

science. “He states that though scientific revolutions leave much

mopping up to do, the central change cannot be experienced

piecemeal, but that it involves some relatively sudden and

unstructured transformation in which some part of the flux of

experience sorts itself out differently and displays patterns

that had not been visible previously”.20 This theory of his

emphasizes on the revolutionary structure of scientific progress

whereby one theory is replaced by a new and incompatible one. A

summary of Kuhn’s theory of scientific progress and be depicted

with a simple format:

Pre-science – normal science – crisis – revolution – new normalscience – new crisis

Kuhn argued that the account of history which have been presented

by scientists “considerably simplify and distort the real story

of theory development and change”.21 This happens because the

20 Thomas J. Hickey (2005), “Thomas Kuhn on Revolution and Paul Feyerabend onAnarchy” op.cit., p. 7.21 James Ladyman, Understanding Philosophy of Science op.cit., p. 97.

primary aims of these summaries are to motivate and justify

contemporary issues and thus ignore the complexities of history.

According to Kuhn, “these historians confront growing

difficulties in distinguishing the scientific compound of past

observations and belief from what their predecessors had labelled

error and superstition”.22 For Kuhn, “if these out-of-date

beliefs are to be called myths, then myths can be produced by the

same sorts of methods and held for the same sort of reasons that

have led to scientific knowledge”.23 Thus for Kuhn the so called

out-of-date theories are not unscientific simply because they

have been abandoned.

In his book, The Structure of Scientific Revolutions, Kuhn states vividly

that normal science means “research firmly based on one or more

past scientific achievements, achievements that some particular

scientific community acknowledges for a time as supplying the

foundation for its further practise”.24 Kuhn further explains

that these achievements are recorded in textbooks, though most

times not in their original form. Also, science classics,

22 Thomas S. Kuhn, The Structure of Scientific Revolutions op.cit., p. 2.23 Ibid.24 Ibid., p. 10.

according to Kuhn, implicitly defend the legitimate problems and

methods of a research field for the posterity of practitioners.

Two essential features made this possible. First, their

achievements were sufficient enough to attract followers away

from other competing scientific activities. Secondly, it was able

to leave problems for the redefined group of practitioners to

solve. For Kuhn, scientific activity which possesses these two

features are paradigms.

Paradigms thus refer to accepted scientific practice which

provides the foundation from which particular coherent traditions

of scientific research spring up. A mature science according to

Kuhn is governed by a single paradigm; the paradigm sets the

standard for the legitimate work within the science it governs.

Scientific research may exist without paradigms but “acquisition

of a paradigm and of the more esoteric type of research it

permits is a sign of maturity in the development of any given

scientific field”.25 Paradigms are what guide the activity of the

normal science. In the words of A.F Chalmers “it coordinates and

directs the puzzle-solving activity of the groups of normal

25 Ibid., p. 11.

scientists who work within it. The existence of a paradigm

capable of supporting a normal science tradition is the

characteristic that distinguishes science from non-science”.26

Kuhn explains that transformations of paradigms in a normal

science are scientific revolutions and the successive transition

from one paradigm to another by the way of revolution is the

usual developmental pattern of mature science. According to Kuhn,

to be accepted as a paradigm, a theory must be better than other

competing theories, the best theory among them is taken as the

paradigm. However, it need not and in fact cannot explain all the

facts with which it can be confronted. Furthermore with the

development of a new paradigm, the old paradigm fades away;

When in the development of a normal science, an individual or groupfirst produces a synthesis able to attract most of the nextgeneration practitioners, the older schools gradually disappear. Inpart this conversion is caused by their members’ conversion to thenew paradigm. But there are always some men who cling to one oranother of the older views. They simply readout of the professionwhich thereafter ignore their work. The new paradigm implies a newand more rigid definition of the field.27

Paradigms gain their status in the scientific field because they

are more successful than other competitors. The success of such

26 A.F. Chalmers, What is this Thing called Science, op.cit., pp. 108- 109.27 Thomas S. Kuhn, The Structure of Scientific Revolutions, op.cit., pp. 18-19.

paradigm begins as a mere “promise of success discoverable in

selected and incomplete examples. Normal science consists in the

actualization of that promise”.28 This actualization comes about

when there is an increase in the extent of the match between

these facts which the paradigm displays and the predictions of

the paradigm and by further articulation of the paradigm itself.

Furthermore, normal science or the activities involved in normal

science does not constitute or drive towards calling new sorts of

phenomena neither is it aimed at constructing new theories. The

activities or the research involved in normal science is the

articulation of the phenomena and theories which are already

supplied by the paradigm. In highlighting a summary of the

activities in Kuhn’s normal science, John Losee puts it thus:

Increasing the precision of agreement between observations andcalculations based on the paradigm, extending the scope of theparadigm to cover additional phenomena, determining values ofuniversal constant, formulating quantitative laws which furtherarticulate the paradigm, and deciding which alternative way ofapplying the paradigm to a new area of interest is mostsatisfactory.29

These activities of normal science which are aimed at

“elaborating and extending is the success of a paradigm”30 leads

28 Ibid., p. 24.29 John Losee, A Historical Introduction to the Philosophy of Science, op.cit., p. 198.30 James Ladyman, Understanding Philosophy of Science op.cit., p. 100.

Kuhn to give a description of normal science as a puzzle solving

activity. The rules for solving puzzles are strict and determined

by the paradigm. “The puzzles will be of both a theoretical and

an experimental nature”.31 An example is given of the Newtonian

paradigm; within it typical theoretical puzzles involve devising

mathematical techniques for dealing with the motion of a planet

subject to more than attractive force, and developing assumptions

suitable for applying Newton’s law to the motion of fluids.

Experimental puzzles included the improvement of the accuracy of

telescopic observations and the development of experimental

techniques capable of yielding reliable measurements of the

gravitational constant.

When a scientist is faced with puzzles within a paradigm, the

scientist must presuppose that the paradigm is capable of solving

such puzzles. According to Kuhn, “one of the things a scientific

community acquires with a paradigm is the criterion for choosing

problems that while the paradigm is taken for granted, can be

assumed to have solutions”.32 Questions of this sort are the only

31 A.F. Chalmers, What is this Thing called Science, op.cit., p. 110.32 Thomas S. Kuhn, The Structure of Scientific Revolutions, op.cit., p. 37.

kind which the scientific community would accept as scientific or

which it would encourage its members to undertake. Other problems

which may be faced by the paradigm are considered metaphysical or

the business of other discipline or are sometimes seen to be too

problematic. Kuhn further states that the paradigm could as well

protect the community from “socially important problems”33 that

cannot able to be reduced to puzzle form because it is not

possible to depict them in terms of the conceptual and

instrumental tools which are provided by the paradigm. According

to him, among the reasons why normal science progresses rapidly

is that its practitioners concentrate on problems that only their

own lack of ingenuity should keep them from solving. A failure to

solve a puzzle is considered to be a failure on the part of the

scientist and not the paradigm.

Kuhn further argues that the discovery or the determination of a

paradigm is prior to the discovery of any rules, of which is

thought, that guides the activities of the scientists in the

scientific community. According to Kuhn, scientists agree in the

identification of a paradigm without agreeing on, or even

33 Ibid.

attempting to produce a full interpretation or rationalization of

it. Lack of a standard interpretation or of an agreed reduction

to rules will not prevent a paradigm guiding research”.34 The

discovery of a normal science can be made by an inspection of a

paradigm which guides the normal science. However, though this

process of discovery may be aided by the rules and assumptions,

it is not dependent on it. Thus “the existence of a paradigm need

not even imply that any full set of rules exists”.35

Kuhn asserts that there are some reasons behind the nature of

priority of paradigms. One reason is that there is the

experience of extreme difficulty in the discovery of rules that

guides the traditions of normal science. He asserts that

scientists within a normal science work from models which have

been received through education without knowing or needing to

know the features that give the models the shape of a paradigm

and as such they do not need any set of rules.

Another reason is that concepts, laws and theories are learnt

with application to some “concrete range of natural phenomena”.36

34 Ibid., p. 4435 Ibid.36 Ibid.

Paradigms are discovered during a search for rules because such a

search to show such rules would come through their ability to do

successful research. In the process of this research, the

paradigm is what is discovered prior to any rule if in existence.

Also, another reason is that normal science can go on in as much

as the scientific community accepts without contestation the

problem-solution which has already been achieved.

Furthermore, the diversity of scientific fields and specialties

are easier to understand with paradigms than with rules. Rules

are usually common to a large number of scientific groups but a

paradigm is not of such nature; it is peculiar to a particular

scientific community. Scientists of different fields are educated

through the different achievements of their fields which have

been described in different books. “And even men who, being in

the same or in closely related fields, begin by studying many of

the same books and achievements may acquire rather different

paradigms in the course of professional specialization”.37

37 Ibid., p. 49.

CHAPTER TWO

KUHN'S REVOLUTIONARY SCIENCE

In the previous discussion on the nature of normal science, we

said that paradigms control the scientific activity or the

puzzle-solving activity of the scientific community. The idea of

a paradigm is imperative to Kuhn's entire theory: normal science

would be non-existent without the existence of a paradigm and his

discourse on revolutionary science centres on the shift between

paradigms. In this chapter we will look at Kuhn’s revolutionary

science and by way of achieving this, we shall try to analyse the

nature of paradigms and his substitutions of the term. We shall

then look into his theory of revolutions.

2.1 Nature of a Paradigm

Paradigms emerge from a period of immature science, a period

marked by disorganised and diverse activities though with the

presence of ongoing scientific research. In this period, the

scientists begin from a period of nothing to establish a

scientific theory, the absence of a paradigm makes this period

consist of simple data collection with no real organising

principle, “consequently there is little opportunity for

collective progress. Even localized progress by a particular

school is made difficult, since much intellectual energy is put

into arguing over the fundamentals with other schools instead of

developing a research tradition”.38 For Kuhn, “the development of

science at this period resembles that of the social sciences and

the arts”.39

Progress comes when a scientist or a school of thought makes a

breakthrough in research whereby the problems which the

scientific schools are attempting to solve are solved through one

theory. This emerging paradigm thus comes out from one of the

theories existing in the community, having beaten off competition

from competing theories.

There are components which make up the paradigm. According to

A.F. Chalmers,

Among these components will be explicitly stated fundamental lawsand theoretical assumptions, Paradigms will also include standardways of applying the fundamental laws to a variety of types ofsituation. some very general, metaphysical principles that guidework within a paradigm. Finally, all paradigms will contain somevery general methodological prescriptions such as, "Make serious

38 Bird, Alexander, "Thomas Kuhn", The Stanford Encyclopedia of Philosophy (Fall 2013Edition), Edward N. Zalta (ed.),http://plato.stanford.edu/archives/fall2013/entries/thomas-kuhn/>.39 Thomas S. Kuhn, “The Function of Dogma in Scientific Research” in Readings inthe Philosophy of Science, edited by Baruch A. Brody (New Jersey: Prentice-Hall, Inc., 1970),p. 361.

attempts to match your paradigm with nature", or "Treat failures inattempts to match a paradigm with nature as serious problems.40

“Normal science involves detailed attempts to articulate a

paradigm with the aim of improving the match between it and

nature”.41 A paradigm will always be sufficiently indefinite and

restricted to leave plenty of work to be done and thus gives

normal science the character of a puzzle-solving activity.

It is in recognition of Kuhn’s theory of a paradigm that Donald

Davidson in his famous article: On the very idea of a Conceptual Scheme,

explains the ideas conceptual schemes. He writes:

Conceptual Schemes, we are told, are ways of organizing experience;they are systems of categories that give form to the data ofsensation; they are points of view from which individuals, cultures,or periods survey the passing scene. There may be no translatingfrom one scheme to another, in which case the beliefs, desires,hopes and bits of knowledge that characterize one person have notrue counterparts for the subscriber to another scheme. Realityitself is relative to a scheme: what counts as real in one systemmay not in another.42

Conceptual schemes here are the same with paradigms, providing

the backbone for the activities of a community, it gives the form

40 A.F. Chalmers, What is this Thing called Science, op.cit., p.109.41 Ibid.42 Donald Davidson, “On the Very Idea of A Conceptual Scheme”, The AmericanPhilosophical Association vol. 47, (1974), p. 1.

from which other things follow. Proponents of a particular scheme

are thus in another world of their own and there may be no

translation from one scheme to another. He argues that we cannot

make sense of any conceptual scheme which differs from our own,

for him “conceptual schemes different from our own must be

untranslatable into our own language and further that the idea of

untranslatable languages does not make sense”.43 Thus as Kuhn says

that scientists operating in different scientific traditions,

that is different paradigms, live in different worlds, so also

does practitioners of varying conceptual schemes live in

different worlds. In his philosophical investigations, Ludwig

Wittgenstein states that “to imagine a language game means to

image a form of life”.44 Wittgenstein describes the language game

as a form of life, he says that “when a person says something

what he or she means depends not only on what is said but also on

the context in which it is said. Importance, point, meaning are

given by the surroundings. Words, gestures, expressions come

43 R.L. Behera, “Donal Davidson on Conceptual Schemes”, Indian Journal of Education,Research Experimentation and Innovation vol.3, (March 2013), p. 244 L. Wittgenstein, Philosophical investigations translated by G.E.M Ascombe, (Oxford:Basil Blackwell Ltd., 1986).

alive, as it were, only within a language game, a culture, a form

of life”.45 J.F.M Hunter says of forms of life that “a form of

life is the same thing as a language game, and calling a

language-game a form of life is saying that it is something

formalized or standardized in our life; that it is one of life's

forms”.46 As previously stated, language game or forms of life,

forms the compound, that paradigm within which words and

expressions come alive, any other thing outside of the language

game and not being guided by it becomes thus meaningless. The

terms paradigm, conceptual scheme and form of life all appear to

the synonyms of each other. Each one of the philosophical terms

relating to the same concept, that is, a standard from which

research, expressions and ideas spring up within a community of

science or a language game or a congregation of ideas each with

its own rules without which there would be no sense at all.

2.2 Senses of a Paradigm

45 Duncan J. Richter “Ludwig Wittgenstein (1889-1951)” Internet encyclopedia ofPhilosophy http://www.iep.utm.edu/wittgens/.46 J. F. M. Hunter, “"Forms of Life" in Wittgenstein's "PhilosophicalInvestigations"”, American Philosophical Quarterly, Vol. 5, No. 4 (Oct., 1968), p.233

It is argued, against Kuhn, that the sense of the term Paradigm

is equivocal. In this respect, Dudley Shapere and Gerd Buchdahl

criticized Kuhn for shifting back and forth between a broad sense

and a narrow sense of ‘paradigm’. For them, if the sense in which

Kuhn intends to use is the narrow sense, then “the contrast

between normal science and revolutionary science is greatly

reduced. Thus instead of talking about “articulations of a single

paradigm”, the historian would have to discuss a succession of

distinct exemplars. And on the other hand, if it is the broad

sense of “paradigm” that Kuhn has in mind, then the concept is

too vague to be useful as a tool of historical analysis”.47 Kuhn

admits to the usage of the word in two different senses. He

identifies the usage of paradigms as exemplars on the one hand

and as disciplinary matrix on the other, though not explicitly

stated. He says that

On the one hand, it stands for the entire constellation of beliefs,values, techniques, and so on shared by the members of a givencommunity. On the other, it denotes one sort of element in thatconstellation, the concrete puzzle-solutions which, employed as modelsor examples, can replace explicit rules as a basis for the solution ofthe remaining puzzles of normal science.48

47 John Losee, A Historical Introduction to the Philosophy of Science, op.cit., p. 20148 Thomas S. Kuhn, The Structure of Scientific Revolutions, op.cit., p. 175.

In the first sense pointed out by Kuhn, he refers to paradigms as

exemplars; this use of the term is in a narrow sense. It refers

to those successful parts of science that all those beginning

scientists learn, and which will provide them with a frame work

or back bone for the future development of their subject. “Anyone

familiar with a modern scientific discipline will recognise that

teaching by example plays an important role in the training of

scientists”.49 With the use of textbooks which are full of

standard problems and their solutions, students are set exercises

that require them to adapt the techniques used in the examples

and apply them to new situations in order that the students, if

they have the predisposition for it, learn how to apply these

techniques to new kinds of problems that nobody has been able to

solve.

This sense of exemplars Kuhn took to be the standard sense of the

word since it is the already conventional sense of the word. A

person who has lived a life worthy of emulation might be called a

paradigm of virtue if his or her behaviour is to be emulated or a

person’s work may be called a paradigm if it becomes the

49 James Ladyman, Understanding Philosophy of Science, op.cit., p. 99

framework of later generations. To pass through an instance:

“Plutarch’s live was regarded for centuries as the paradigm of

biographical writing and, as such, their form was taken as a

template and their style copied by many writers; art students who

copy the drawings of Raphael or musicians who learn to harmonize

in the manner of a Bach chorale take the works of past masters as

paradigms”.50 Thus paradigms in this narrow sense; as exemplars

are simply “stated, augmented and revised in textbooks which

contain illustrations and applications of a theory”.51

In this deeper sense, paradigm is a disciplinary matrix or “an

entire constellation of beliefs, values, techniques and so on

shared by the members of a given community. Members of a

community of practitioners may share a commitment to the

existence of theoretical entities. In addition, the members may

be in agreement about which types of investigation and

explanation are important. Such commitments and beliefs are part

of a “paradigm” in the broad sense”.52 Kuhn conceding that his

50 Alexander Bird, Philosophy of Science (Edinburgh: Taylor and Francis Group,2006), p. 18151 John Losee, A Historical Introduction to the Philosophy of Science, op.cit., p. 20152 Ibid., pp. 200-201.

use of the term ‘paradigm’ had been somewhat equivocal, then

substitutes ‘paradigm’ for ‘disciplinary matrix. He says that:

As currently used in philosophy of science…‘theory’ connotes astructure far more limited in nature and scope than the one requiredhere. Until the term can be freed from its current implications, itwill avoid confusion to include another. For present purposes Isuggest ‘disciplinary matrix: ‘disciplinary because it refers to thecommon possession of the practitioners of a particular discipline;‘matrix’ because it is composed of ordered elements of varioussorts, each requiring further specification.53

2.3 Scientific Revolution

This puzzle-solving activity, which is normal science, is very

successful in its aim, according to Kuhn, of expanding the scope

and precision of scientific knowledge. A normal science which is

successful, does not necessarily aim to discover novelties of

facts and theories, but in the course of expansion of research,

and the meeting of anomalies, scientists always discover new

theories and new phenomena are discovered. Under research

scientists discover new theories. According to Kuhn, this game of

consistent discovery of novelties and theories within the

community makes it an effective way to bring about a paradigm

change. He says that:

That is what fundamental novelties of fact and theory do. Producedinadvertently by a game played under one set of rules, their

53 Thomas S. Kuhn, The Structure of Scientific Revolutions, op.cit., p. 182.

assimilation requires the elaboration of another set. After theyhave become parts of science, the enterprise, at least of thosespecialists in whose particular field the novelties lie, is neverquite the same again.54

Within the research which is conducted by scientists operating

with a particular paradigm the community, anomalies emerge. These

anomalies represent the first stage in the actualization of a

scientific revolution, however, anomalies do not immediately

bring about a crisis, some anomalies only lead to novelties and

they are easily dealt with by the scientists. Kuhn explains that

the normal reaction to anomalies is a modification of the

articulate rules and theories associated with the articulate

paradigm so that the anomalous fact can be assimilated. Success

in such modification is a significant achievement for a normal

science researcher.

There are other anomalies which may not be assimilated, the

scientists would normally set them aside under the assumption

that eventually they will be reconciled, and normal science

research continues with the consensus paradigm. “Scientists are

not easily distracted by anomalies from continued exploration of

54 Ibid., p. 52.

the promise of a generally still satisfactory paradigm”55; since

the paradigm remains largely successful, able to account for the

bulk of phenomena in its domain and if scientist are able to

solve problems and still expand its empirical applications, then

anomalies are set aside with the assumption that those anomalies

will eventually be taken care of by the paradigm. Kuhn here

rejects Karl Poppers falsificationism according to which

scientists do and should abandon any refuted theory, for him the

falsifying of a particular theory is not enough to completely

reject the theory and thus abandon it. The scientists will not

surrender the theory simply because it conflicts with a

particular evidence. According to Kuhn, scientists do not give

attention to all anomalies, “the scientist who pauses to examine

every anomaly he notes will seldom get significant work done”.56

The discoveries of new phenomena and anomalies begin the process

of a scientific revolution; however, though they are contributors

to the revolution, they do not and cannot solely bring about a

revolution but will rather lead to a higher and a more difficult55 Thomas J. Hickey (2005), “Thomas Kuhn on Revolution and Paul Feyerabend onAnarchy”, op.cit., p. 260.56 Thomas S. Kuhn, The Structure of Scientific Revolutions op.cit., p. 82.

situation. The presence of few anomalies experienced during

research within a paradigm, will not bring a problem to the

scientific community but the more anomalies are kept aside, they

begin to increase and they also become more serious. Then “those

modification which assimilate those anomalies which can be

assimilated, produce a certain amount of paradigm destruction”.57

This is then the period of crises within the community and this

situation of crises leads the scientist to begin the search for

alternative theories and thus to the invention of such theories.

According to Kuhn this situation seldom occurs in the evolution

of a paradigm, he says that:

But that invention of alternates is just what scientists seldomundertake except during the pre-paradigm stage of their science’sdevelopment and at very special occasions during its subsequentevolution. So long as the tools a paradigm supplies continue toprove capable of solving the problems it defines, science movesfastest and penetrates most deeply through confident employment ofthose tools. The reason is clear. As in manufacture so in science—retooling is an extravagance to be reserved for the occasion thatdemands it. The significance of crises is the indication theyprovide that an occasion for retooling has arrived.58

The period of crises is a necessary precondition for the

emergence of novel theories. Having been lead into confusion by

57 Thomas J. Hickey (2005), “Thomas Kuhn on Revolution and Paul Feyerabend onAnarchy” op.cit., p. 261. 58 Thomas S. Kuhn, The Structure of Scientific Revolutions, op.cit., p.76.

the severe and prolonged anomalies which have hit the existing

paradigm and its theories, the scientists begin to lose faith and

then to consider alternatives. However, Kuhn states that this

loss of faith does not lead to an immediate renouncement of the

paradigm that has led them into crises. Kuhn states that “once it

has achieved the status of a paradigm, a scientific theory is

declared invalid only if an alternate candidate is available to

take its place”.59 He says further that it does not mean that

scientists do not reject scientific theories or that experience

and experiments do not make up an essential part of why

scientists reject theories, but it means that

the act of judgement that leads scientists to reject a previouslyaccepted theory is always based upon more than a comparison of thattheory with the world. The decision to reject one paradigm is alwaysthe simultaneous decision to accept another, and the judgementleading to that decision involves the comparison of both paradigmswith nature and with each other.60

Furthermore, Kuhn explains that there is a second reason why

scientists do not simply reject a paradigm when confronted by

anomalies or counter instances. He explains that counter

instances will only create crises or fortify already existing

59 Ibid., p. 77.60 Ibid.

crises but will be unable to falsify the scientific theory

because the defenders of that theory will do what scientists do

when they are confronted by anomaly. They will device numerous

articulations and ad hoc modifications of their theory in order to

eliminate the conflict”61

Kuhn states that there are some men who have been driven to

reject science because of their inability to tolerate crises. But

this rejection of science in favour of another occupation is,

according to Kuhn, the only kind of paradigm rejection which

counter-instances solely can lead. He states that “like artists,

creative scientists must occasionally be able to live in a world

out of joint”.62 He asserts that once a paradigm through which

nature is viewed has been found, there is nothing like research

in the absence of a paradigm. If a scientist rejects a paradigm

without accepting another paradigm or without simultaneously

substituting another, it is equivalent to a total rejection of

science itself. Such an act reflects not on the paradigm but on

61 Ibid., p. 78.62 Ibid., p.79.

the scientists and he will be viewed as “the carpenter who blames

his tools”.63

Kuhn further states that there is also no such thing as research

without counterinstances. Counter-instances provide the

difference between normal science and science in a crisis state;

it is not the case that normal science does not confront

counterinstances but “puzzles which constitute normal science

exists because no paradigm that provides a basis for scientific

research ever completely resolves all its problems”.64 However,

Kuhn states that every problem which is seen by normal science as

a puzzle can be seen from another point of view as a

counterinstance and thus as a source of crises. The presence of a

crisis does not ultimately transform, by itself, a puzzle into

counterinstance but by proliferating versions of the paradigm,

Kuhn states that crisis loosens the rules of normal puzzle-

solving in ways that ultimately permit a new paradigm to emerge.

Furthermore, Kuhn states that if an anomaly is to evoke crisis,

it must be more than just an anomaly. The scientist will not

63 Ibid.64 Ibid.

examine all anomalies but then what makes an anomaly worth

scrutinizing and giving attention? To this Kuhn says there is no

fully general answer. He says that sometimes, the anomaly will

call into question explicit and fundamental generalizations of

the paradigm, or an anomaly without apparent fundamental import

may evoke crisis if the applications that it inhibits have a

particular practical importance. Also, it could happen that the

development of normal science may transform an anomaly that had

previously been only a vexation into a source of crisis. Kuhn

says that when for these or other like reasons an anomaly comes

to be seen as more than just any other puzzle, “the transition to

crisis and to extraordinary science has begun”.65 The anomaly

comes to be more generally recognised as such by the profession.

The anomaly attracts more and more attention from the fields’

distinguished men and if it still continues to resist, many of

the scientists may come to view its resolution as the subject

matter of their discipline. For them, the field will begin to

look different. The continual resistance of the anomaly will

ignite some minor articulations of the paradigm which, though

65 Ibid., p.82.

maybe partially successful, will not be sufficient to be accepted

as a paradigm. Though the paradigm remains only a few of its

practitioners will agreed on its rules and what it is, even

formerly solved problems will be called into question.

According to Kuhn, “all crises begin with the blurring of a

paradigm and the consequent loosening of the rules for normal

research”.66 In this regard, research done in the period of crises

resembles research in the pre-paradigm period but the research

done in the period of crises has more precision and definition

than in the pre-paradigm period. Kuhn further states that there

are three ways in which crises may come to a close. First,

sometimes normal science proves itself capable of handling the

paradigm threatening crises despite the desolation of those who

have lost hope on the paradigm. Second, the problem could resist

all forms of approaches made by the defenders of the paradigm.

This will lead the scientists to the conclusion that no solution

will come from the present currency of their field and will then

set the problem aside hoping that posterity will provide a

solution. Thirdly and finally, a crisis will end with the birth

66 Ibid., p. 84.

of a new candidate for paradigm and the battle for the acceptance

of the paradigm begins.

Furthermore, the transition from a paradigm in crisis to a new

paradigm from which a new tradition of normal science arises,

says Kuhn, is not a cumulative process, that is, the new paradigm

does not erupt as an extension of the old paradigm. Kuhn says

that it is

Rather a reconstruction of the field from new fundamentals, areconstruction that changes some of the field’s most elementarytheoretical generalizations as well as many of its paradigms methodsand applications. During the transition period there will be a largebut never complete overlap between the problems that can be solvedby the old and the new paradigm. But there will also be a decisivedifference in the modes of solution. When the transition iscomplete, the profession will have changed its view of the field,its methods, and its goals.67

Consequently, the transition from an old paradigm to a new one is

not cumulative; the new paradigm which has come as a result of

crises becomes totally incompatible with the old paradigm. Thus

the tradition of the normal science is changed, the methods of

scientific research takes another direction for the goals of the

profession has itself changed. Therefore according to Kuhn

scientific revolutions are non-cumulative developmental episodes.

67 Ibid., p. 85.

He further says that if new theories are invented for the sake of

resolving anomalies in the relation of an existing theory to

nature, then the predictions permitted by the new theory must

differ from that of the old and that difference will not happen

if both theories were logically compatible. Thus the new theory

must displace the first one.68

Kuhn further gives the functions which paradigms and revolutions

play. According to him, periods of normal science provides

scientists with the opportunity to develop the cryptic details of

a theory. While working within the frame of a particular

paradigm, they are able to perform experiments and theoretical

works necessary to increase the complementarities between the

paradigm and nature. Since the scientists are already confident

of the paradigm, they devote greater part of their energy in

solving puzzles which they experience in the paradigm. More so,

if all scientists were critical of all parts of the paradigm at

all times, little or no work will get done hence it is necessary

that normal science remains largely uncritical.

68 Ibid., p. 97.

That normal science should remain uncritical, as asserted by

Kuhn, does not imply that the scientists should remain locked up

in a single paradigm for an entire lifetime. If they remained

normal scientists, it makes it impossible for the progress of

science to occur. “A paradigm embodies particular framework

through which the world is viewed and described, and a particular

set of experimental and theoretical techniques for matching the

paradigm with nature”.69 However there is no reason to expect that

a paradigm is perfect neither are there any procedures of

arriving at a perfect paradigm. Thus there should be within

science, a means of breaking out of one paradigm in to a better

one. This, according to Kuhn, is the function of revolutions.

Paradigms will at some point be inadequate in its match with

nature, when this match becomes serious, a crisis arises and then

the revolutionary step of replacing an entire paradigm with a new

incompatible and incommensurable one becomes very necessary for

the sake of progress in science.

Furthermore, Kuhn argues that successive paradigms are both

necessary and irreconcilably different in some aspects. Mainly,

69 A.F. Chalmers, What is this Thing called Science, op.cit., p. 118.

“successive paradigms tell us different things about the

population of the universe and about that population’s behaviour.

And they differ, that is, about such questions as the existence

of subatomic particles, the materiality of light and the

conservation of heat or of energy”.70 These Kuhn says are the

substantive differences between successive paradigms. However, he

further says that paradigms differ in more than substance, for

they are directed not only to nature but also back upon the

science that produced them. They are the sources of methods,

problem-field, and standard of solution accepted by any mature

scientific community at any given time. As a result, the

reception of a new paradigm often necessitates a redefinition of

the corresponding science. Some old problems may be relegated to

another science or ultimately declared unscientific. Others that

were previously non-existent or trivial may, with a new paradigm,

become the very archetypes of significant scientific achievement.

Thus implying that when paradigms change, so often, does the

standard that distinguishes a real scientific solution from a

mere metaphysical speculation, word game, or mathematical play.

70 Thomas S. Kuhn, The Structure of Scientific Revolutions, op.cit., p. 125.

More so, paradigm change or revolution changes the world view of

the scientists, it seems as if the world changes with the

paradigm. Scientists now see the world of their research

differently. He says that:

Led by a new paradigm, scientists adopt new instruments and look inthe new places. Even more important, during revolutions scientistssee new and different things when looking with familiar instrumentsin places they have looked before.71

Newton-Smith opines that “if by ‘change of world view’ we mean a

change in our basic beliefs and/or attitudes, this is merely a

trivial consequence of the fact that in changing paradigms we are

changing our theoretical assumptions”.72 The occurrence of a

paradigm shift involves the change of some of our deeply held

beliefs about the world.

Kuhn likens paradigm shift to a gestalt switch, he says that the

transformation which occurs in the world views of the scientist

is something more or less like a gestalt switch. The gestalt

switch presents a duck rabbit/image, at first glance the image is

seen as a duck and then later on that same picture is seen as a

71 Ibid., p. 111.72 W.H. Newton-Smith, The rationality of science (London: Routledge and Kegan PaulLtd., 1981), p. 117.

rabbit. Kuhn says that the change in world view of the scientists

is in similarity to the gestalt switch, the scientist sees the

world from a particular point of view under a particular paradigm

and then the world view changes in respect to change in paradigm

though the world remains the same.

According to Newton-Smith, there are two obvious ways in which a

theoretical change can bring about a shift in the perception of

the world. First, “it will affect the way we describe the objects

which are the causes of our visual experience. Second, a shift in

the paradigm may influence not only how we perceive what we see,

it will also affect where and how we look at and for things”.73 He

gives the example of Uranus being accepted as a previously

unknown planet, the acceptance of this spurred the search for

other planets thus leading to the discovery of asteroids and

other planets.

When, therefore, the normal science tradition changes, that is,

at times of revolution, the scientist’s perception of the

environment must be re-enlightened and must learn to see the new

73 W.H. Newton-Smith, The rationality of science, op.cit., pp. 118-119.

gestalt. After this re-enlightenment, the world of his research

will be incommensurable with the previous paradigm. That is why

schools guided by different paradigms are always slightly at

cross purposes. Thus the proponents of differing paradigms will

to some extent experience difficulty even communicating with each

other, because they will use the same terms to mean different

things.

CHAPTER THREE

INCOMMENSURABILTY

3.1 What is Incommensurability?

The mathematical term incommensurable according to the New

Webster’s Dictionary of the English Language means “having no common measure

or basis of comparison, having no common integral divisor”.74

74 The New Webster’s dictionary of the English Language (1997), s.v.“incommensurability”, ed. Donald Bolander et. al., International Edition. (New York: Lexicon Publications).

Terms being incommensurable imply that there is no way that

either terms could be measured or compared. In the field of

philosophy of science, incommensurability is a relation of

incomparability, purported to obtain between some pairs of

successive or competing scientific theories. The term was

employed and developed upon in the philosophy of science by Paul

Feyerabend and Thomas Kuhn although both of them do not apply the

term to exactly the same cases.

Feyerabend’s argument for the incommensurability of scientific

theories stems from his critique of the “empiricist idea of a

theory-neutral observation language”75which claims that the

meaning of observational terms are independent of theories. He

argues against the reductionist idea of the empiricist. He says

What happens . . . when a transition is made from a theory T’ to awider theory T (which . . . is capable of covering all the phenomenathat have been covered by T’) is something much more radical thanincorporation of the unchanged theory T’ (unchanged, that is, withrespect to the meanings of its main descriptive terms as well as tothe meanings of the terms of its observation language) into thecontext of T. What does happen is, rather, a replacement of theontology (and perhaps even of the formalism) of T’ by the ontology(and formalism) of T, and a corresponding change of the meanings ofthe descriptive elements of the formalism of T’ (provided theseelements and this formalism are still used). This replacement

75 Howard Sanky, “Incommensurability”, The Philosophy of Science: An Encyclopedia ed.Sahotra Sarkar and Jessica Pfeifer, 2006 ed., p. 370.

affects not only the theoretical terms of T’ but also at least someof the observational terms which occurred in its test statements.76

For Feyerabend, a change in theoretical ontology will lead to

variation in the meaning of the vocabulary employed by theories.

Hence it is not possible for one theory to be deductively

subsumed by another, due to differences in the meaning of the

terminology employed by the theories. The failure of reduction,

for Feyerabend, occurs due to incommensurability; there is no

equivalence in the vocabulary employed by different theories. He

further argues that the concept of one theory cannot be defined

based on the concepts of another and further, no empirical

statement can be possibly made which will correlate the concepts

of one theory with another. Theories therefore are incompatible

with each other and as such incommensurable.

From Kuhn’s progression from normal science to revolutionary

science, we see the paradigm shift that occurs from one paradigm

to the other and more precise to an incompatible paradigm.

76 Paul Feyerabend, ‘‘Explanation, Reduction and Empiricism’’ in Realism,Rationalism and Scientific Method: Philosophical Papers, vol. 1. (Cambridge: Cambridge University Press,1962). p. 44 .

Scientists move from an old paradigm which has been hit severely

with crisis and as such can no longer perform its function and

then move to a new paradigm which is not compatible with the old

one. A battle thus ensues between defenders of the old paradigm

and advocates of a new one. This battle is characterised by the

lack of communication between both paradigms due to

incommensurability. Kuhn argues that “there is no higher standard

for comparing theories than the assent of the relevant community,

and that the choice between competing paradigms proves to be a

choice between incompatible modes of community life”.77

That theories from different paradigms are incommensurable is the

reason why Kuhn’s picture of science is often called relativist;

it is seen as implying that the standards of rationality are

relative to a paradigm, not absolute. For Kuhn, there are two

sources of incommensurability. The first is the fact that the

standards or methods of theory accessibility and evaluation are

paradigm relative. The second is the claim that the meanings of

the terms used in the competing theories or paradigms are not the

same. So that, while two theories may seem to contradict one

77 Thomas S. Kuhn, The Structure of Scientific Revolutions, op.cit., p. 94.

another, this is in fact a matter of equivocation. This theory

can be explained with the example of “an encounter between a

proponent of Newtonian mechanics and a proponent of relativistic

mechanics. Even though both may express their theories in English

and to a large extent use the same words, it does not follow that

they mean the same thing by these words”.78 For Kuhn, the shift

which has occurred is so extreme that it is not possible for the

concepts of one theory to be expressed in terms of the concepts

in another theory. Thus both theories can in no way be compared.

“If this were the case one would have to say that while the two

theoreticians appeared to say incompatible things about mass or

time or space, they were in fact merely equivocating”.79

According to Kuhn, the incommensurability of competing paradigms

is due to differences that arise at three levels between

paradigms. The first difference involves variation at the

methodological level. Paradigms address different problem-solving

agendas and employ different standards of theory appraisal. The

second difference is at the semantic level. There is variation in

78 W.H. Newton-Smith, The rationality of science, op.cit., p. 10.79 Ibid.

the concepts employed by paradigms, which leads to change in the

meanings of the terms that express key scientific concepts. The

third difference relates to the theory-dependence of observation.

Not only do scientists observe different things, also the content

of their perceptual experience when they observe the same thing

depends upon the paradigm in which they work. These different

levels between paradigms will lead us to the types of

incommensurability.

3.2 Types of Incommensurability

The types of incommensurability which can be found in Kuhn's work

and which shall be discussed here are the methodological,

observational, early semantic and later semantic

incommensurability

3.2.1 Methodological Incommensurability.

Methodological incommensurability, in Kuhn’s thesis, arises in

science because puzzle-solutions from different eras of normal

science are evaluated by reference to different paradigms. The

methods by way of providing solutions to problems as well as

accessing data vary in accordance to particular paradigms.

According to Philip Kitcher, “the methods and standards of

evidence employed by the parties to a revolutionary debate are

not constant. Opinions diverge about what problems are most

important and about the constraints that are to govern adequate

solutions”.80 According to Kuhn, “the proponents of competing

paradigms will often disagree about the list of problems that any

candidate for paradigm must resolve. Their standards or their

definitions of science are not the same”.81

In general, “the factors that determine our choices of theory

(whether puzzle-solutions or potential paradigm theories) are not

fixed and neutral but vary and are dependent in particular on the

disciplinary matrix within which the scientist is working”.82 For

Kuhn, “there is no neutral algorithm for theory-choice, no

systematic decision procedure which, properly applied, must lead

each individual in the group to the same decision”.83 Thus even

among scientists working within the same disciplinary matrix,80 Philip Kitcher, “Implications of Incommensurability” in The Philosophy of ScienceAssociation vol. 281 Thomas S. Kuhn, The Structure of Scientific Revolutions, op.cit., p. 148.82 Bird, Alexander, "Thomas Kuhn", The Stanford Encyclopedia of Philosophy, Loc.cit. 83 Thomas S. Kuhn, The Structure of Scientific Revolutions, op.cit., p. 200

there is no guarantee that they would arrive at the same

evaluation of a theory since there is no algorithm for theory

choice. However here there is less divergence than when the

difference is between theories in different disciplinary

matrices.

According to Kuhn, there are five characteristics or values to

which scientists in a particular paradigm or disciplinary matrix

adhere:

First, a theory should be accurate: within its domain, that is,consequences deducible from a theory should be in demonstratedagreement with the results of existing experiments and observations.Second, a theory should be consistent, not only internally or withitself, but also with other currently accepted theories applicableto related aspects of nature. Third, it should have broad scope: inparticular, a theory's consequences should extend far beyond theparticular observations, laws, or subtheories it was initiallydesigned to explain. Fourth, and closely related, it should besimple, bringing order to phenomena that in its absence would beindividually isolated and, as a set, confused. Fifth-a somewhat lessstandard item, but one of special importance to actual scientificdecisions-a theory should be fruitful of new research findings: itshould, that is, disclose new phenomena or previously unnotedrelationships among those already known.84

84 Thomas S. Kuhn, “objectivity, value and judgement”. In The essential Tension:Selected Studies in Scientific Tradition and Change, Thomas Kuhn (Chicago: The University ofChicago Press, 1977), quoted in Yuri Balashov and Alex Rosenberg ed.,Philosophy of Science Contemporary Readings (London: Routledge Publications, 2002), p.421.

These five characteristics pointed out by Kuhn are all standard

criteria for evaluating the adequacy of a theory and they provide

the shared basis of a theory choice. However, these

characteristics do not remove incommensurability because it still

depends on the paradigm to determine what counts as fruitfulness,

broad scope, accuracy, simplicity and consistency, and different

paradigms could also weigh them differently. Ladyman explains

this thus:

Taking accuracy, for example, accuracy is a matter of a theoryfitting the data. Data are what we get from observation. But,according to Kuhn, what we observe is itself dependent on aparadigm. We encounter again the theory dependence of observation.Or, take simplicity. Someone might regard the mechanics of thespecial theory of relativity as comprising a set of elegantly simpleequations; alternatively, one might regard the retreat fromEuclidean geometry as giving up on simplicity.85

Furthermore, Kuhn states that there are two sorts of difficulties

which are normally encountered by those who use these criteria in

choosing between paradigms. “First, individually, these criteria

are imprecise: individuals may, for example, differ in their

application to concrete terms cases. Second, when they are

employed together, they repeatedly prove to conflict with one

85 James Ladyman, Understanding Philosophy of Science, op.cit., pp.184-185.

another; accuracy may, for example, dictate the choice of one

theory, and the scope the choice of its competitor”.86 Accuracy

according to Kuhn is the most decisive of all the criteria

because it is less equivocal than the others and because

predicative and explanatory powers which are essential to the

scientists, depend on accuracy. However, the accuracy of a theory

cannot save the theory from discrimination or outright rejection.

Copernicus’ system, as exemplified by Kuhn, was not more accurate

than Ptolemy’s until it was revised by Kepler more than sixty

years after the death of Copernicus. The point here is that if

Kepler had not found other reasons to choose heliocentric

astronomy, then the improvements made on the accuracy on

Copernicus’ work would not have been made and the work would have

been forgotten. Thus accuracy by itself is insufficient for a

theory choice. Tackling the criterion of consistency, Kuhn

explains that as astronomical theories, both Ptolemy’s and

Copernicus’ theories were both internally consistent, but their

relation to related theories in other fields differed. The same

can be said of the other criteria among the five given, used

86 Ibid.

individually they are not sufficient for the choice of a theory.

Kuhn states that when scientists must choose between competing

theories, two men who are fully committed to the same criteria of

theory choice may still reach different conclusions. Probably

they may interpret simplicity differently or have different

understandings of the fields to which the criterion of

consistency should be met in a theory.

According to Kuhn, there is the possibility of finding out the

reasons why a scientist chose a particular theory at a particular

time, but in doing that one would have to go beyond the criteria

of theory choice already given to the characteristics of the

individual who made the choice. Here we would then have to deal

with different characteristics in accordance with different

individual scientists.

3.2.2 Observational Incommensurability

Methodological incommensurability shows that there cannot be any

universal methods of making inferences from data. But Kuhn

explains that even if there were any methods, incommensurability

would still not be avoided because the scientists could still

disagree on the nature of the observational data.

This source of incommensurability Kuhn took to be the most

important. He focused on the nature of perceptions and set out to

explain that observations of the scientists changes as a result

of a revolution. Together with Hanson, this view was developed

into what became the thesis of the ‘theory-dependence of

observation’. Kuhn denies that there is a neutral observation,

language and claims that practitioners of a paradigm learn to

report their observations in a paradigm-laden manner. According

to Ladyman, “if it is true that all observations are contaminated

by background theories then the merits of each paradigm cannot be

compared by subjecting them to experimental test because the

proponents of the competing paradigms will not necessarily agree

about what is observed”.87 This is in line with Kuhn's position

which holds that “observations of scientists are influenced by

prior beliefs and experiences, thus it cannot be expected that

87 Ibid., p. 116.

two scientists when observing the same scene will make the same

theory-neutral observations”.88

Perhaps, different paradigms have their own ways of reporting

observations, advocates of competing theories will not

characterise what they see in the world in the same way. Hence,

Kuhn speaks of scientists working in different paradigms as

living in different worlds. Here Kuhn does not deny the existence

of a real and objective world which does not change according to

the changes in our theories or paradigms; neither does he create

a world of the scientists different from this normal world. As

Kuhn puts it:

Both are looking at the world, and what they look at has notchanged. But in some areas they see different things, and they seethem in different relations one to the other. That is why a law thatcannot even be demonstrated to one group of scientists mayoccasionally seem intuitively obvious to another. Equally, it iswhy, before they can hope to communicate fully, one group or theother must experience the conversion that we have been calling aparadigm shift. Just because it is a transition betweenincommensurables, the transition between competing paradigms cannotbe made a step at a time, forced by logic and neutral experience.Like the gestalt switch, it must occur all at once (though notnecessarily in an instant) or not at all.89

88 Bird, Alexander, "Thomas Kuhn", The Stanford Encyclopedia of Philosophy, Loc.cit.89 Thomas S. Kuhn, The Structure of Scientific Revolutions, op.cit., p. 150.

For Kuhn there is no step by step or gradual process in the

transition between competing and incommensurable paradigms, the

switch must happen all at once. More so, “Kuhn argued that the

rigorous training required for admittance to a paradigm

conditions scientist's reactions, expectations and beliefs, so

that learning how to apply the concepts of a theory to solve

exemplary problems determines scientists' experiences”.90 For

instance, where a proponent of the Newtonian theory sees a

pendulum, an Aristotelian saw constrained free fall; where a

disciple of Priestley saw dephlogisticated air, that of Lavoisier

saw oxygen; where Berthollet saw a compound that could vary in

proportion, Proust saw only a physical mixture.

3.2.3 Early Semantic Incommensurability

Incommensurability is seen, in Kuhn’s Thesis, in accordance with

the concepts and terms employed by different paradigms. According

to Kuhn, since the new paradigms are born from old ones, they

90 Oberheim, Eric and Hoyningen-Huene, Paul, "The Incommensurability ofScientific Theories", The Stanford Encyclopedia of Philosophy (Spring 2013 Edition), Edward N. Zalta (ed.), http://plato.stanford.edu/archives/spr2013/entries/incommensurability/>.

incorporate much of the vocabulary and apparatus, both conceptual

and manipulative that the traditional paradigm had previously

employed. However the new paradigms less often employ these

borrowed elements in the same way that the traditional paradigm

employed them. He states that “within the new paradigm, old

terms, concepts, and experiments fall into new relationships one

with the other. The inevitable result is what we must call,

though the term is not quite right, a misunderstanding between

the two competing schools”.91 Thus if we have two distinct

theories then their terms will differ in meaning, even if the

words are the same. Kuhn gives the example of the word “mass”, as

used in Newton and Einstein. According to him, the term as

employed by both scientists differed in meaning. According to

Newton, mass is conserved, while in Einstein’s theory mass is not

conserved but can be converted into and from energy. Thus the two

physicists must have meant different things by the term “mass”.

Furthermore, Kuhn believes meaning is holistic. Thus he advocates

the interrelatedness of the meaning of terms according to which

the meaning of one term changes the meanings of other related

91 Thomas S. Kuhn, The Structure of Scientific Revolutions, op.cit., p. 149.

terms. This belief is observed in his example of how the meaning

of the term mass differs in Newton and Einstein, “to make the

transition to Einstein’s universe, the whole conceptual web whose

strands are space, time, matter, force, and so on, had to be

shifted and laid down again on nature whole”.92 Thus the change

in the meaning of a term employed in the traditional paradigm

would also spur the change in the meaning of other related terms

in the new paradigm.

Furthermore, Kuhn concurs with Quine’s thesis of the

indeterminacy of translation. They both rejected the idea that

the vocabulary of a language can be assigned meaning independent

of the theories presented in the language. Hence for Kuhn, there

is no neutral language in which one can compare paradigms. The

result is that the competing parties in a scientific revolution

mostly resort to extra-rational means to settle their dispute.

3.2.4 Later Semantic Incommensurability

In later works, Kuhn links the translation failure between

disciplinary matrices to change of classification. He refines his

92 Ibid.

incommensurability thesis and brings about another version known

as the local incommensurability. Howard Sankey explains that the

notion of local incommensurability involves “the failure to

translate between localised clusters of interdefined terms”.93

Kuhn states that

The claim that two theories are incommensurable is the claim thatthere is no language, neutral or otherwise, into which boththeories, conceived as sets of sentences, can be translated withoutresidue or loss… most of the terms common to the two theoriesfunction the same way in both: their meanings, whatever they maybe,are preserved: their translation is simply homophonic. Only for asmall subgroup of usually interdefined terms and for sentencescontaining them do problems of translatability arise.94

Kuhn continues to link translation failure with change of

classification. He states that “incommensurability arises from

differences in classificatory schemes”.95 This description he

terms taxonomic incommensurability. According to Kuhn, there must

be some sort of lexical taxonomy in place before any description

of the world can begin. Shared taxonomic categories are

imperative to unproblematic communication, including

communication required for truth claims. If speech communities,

93 Howard Sankey, “Kuhn’s Changing Concept of Incommensurability”, British Journalof Philosophy of Science, vol.44, no.4 (1993), p.771.94 Ibid.95 Bird, Alexander, "Thomas Kuhn", The Stanford Encyclopedia of Philosophy, Loc.cit.

according to Kuhn, have different taxonomies, then members of one

of the communities can be able to make statements that though are

meaningful within that speech community, will not be able to be

articulated by members of the other speech community.96

“In the transition between theories, both criteria of

classification and membership of taxonomic categories undergo

change”.97 At the semantic level, taxonomic change gives rise to

differences in meaning to some of the vocabulary inherited by the

new paradigm from the old, as well as the introduction of

vocabulary which has new meanings. Because taxonomic change

involves change of interconnected categories, the meanings of the

terms affected by such change are related in a holistic manner.

For Kuhn, incommensurability here is at parallel with

untranslatability, he states thus:

Incommensurability thus becomes a sort of untranslatability,localized to one or another area in which two lexical taxonomiesdiffer. The differences which produce it are not any olddifferences….. Violations of those sorts do not bar intercommunityunderstanding. Members of one community can acquire the taxonomyemployed by members of an-other, as the historian does in learning

96 Thomas S. Kuhn, The Road Since Structure, (Chicago: University of Chicago Press,2000). p. 4.97 Howard Sanky, “Incommensurability”, The Philosophy of Science: An Encyclopedia ed.Sahotra Sarkar and Jessica Pfeifer, 2006 ed., p. 372.

to understand old texts. But the process which permits understandingproduces bilinguals, not translators, and bilingualism has a cost,which will be particularly important to what follows. The bilingualmust always remember within which community discourse is occurring.The use of one taxonomy to make statements to someone who uses theother places communication at risk.98

We see that for Kuhn there are no methods or ways in which terms

or the vocabulary of a particular community can be translated in

accordance with another community. Even if they share the same

terms, their meanings would be different, and thus reduces the

possibility of communication among competing theories. Each

theory possesses a central set of interdefined terms, which

cannot be translated in piecemeal fashion into the vocabulary of

a theory with a different taxonomic structure.

The problematic nature of translation, as developed by Kuhn,

arises from two assumptions. First, Kuhn takes meaning to be

holistic as previously stated, implying that meaning is holistic.

A change in the meaning of one part of the lexical structure will

result in a change to all its parts. The consequence of this to

translation is that “it would rule out preservation of the

translatability of taxonomies by redefining the changed part in

98 Thomas S. Kuhn, The Road Since Structure, op.cit., p. 5

terms of the unchanged part”.99 Secondly, Kuhn takes “the ‘no-

overlap’ principle which states that categories in a taxonomy

must be hierarchically organised, that is, if two categories have

members in common, then one must be fully included within the

other; otherwise they are disjoint, they cannot simply overlap.

For example, there are no dogs that are also cats; neither is

there gold which is at the same time silver. This rules out the

possibility of an all-encompassing taxonomy that incorporates

both the original and the changed taxonomies”.100 This principle,

according to Kuhn, is what makes such terms kind terms and by way

of function, kind terms are those terms which are used to state

theories and these kind terms must be learned together through

experience.

He presents two possibilities or ways of learning kind terms;

according to him, most kind terms could be learnt as members of a

particular set or as contrast to another set. For instance, for

one to learn the term liquid, one must also master the terms

solid and gas. “There are other kind terms which cannot be learnt

99 Bird, Alexander, "Thomas Kuhn", The Stanford Encyclopedia of Philosophy, Loc. Cit.100 Ibid.

as contrast sets but must be learnt together with related terms

through their application to situations that exemplify natural

laws. Such that in mastering the term force, the terms mass and

weight have to be learnt through he application of Newton’s three

laws of motion or Hooke’s law”.101 Furthermore, through

revolution, the no-overlap principle breaks due to the fact that

during revolution, the relational structure between pre-existing

kind terms breaks. Thus terms becomes mutually exclusive to one

another, such that a kind term from one taxonomy will not fit

into another taxonomy because the object to which the kind terms

refers will be subjected to a different kind of law. Thus the

consequence of this would be “conflicting expectations about the

same objects, loss of logical relations between statements made

with those concepts, and ultimately incoherence and

miscommunication”.102

101 Oberheim, Eric and Hoyningen-Huene, Paul, "The Incommensurability ofScientific Theories", The Stanford Encyclopedia of Philosophy, Loc.cit.102 Ibid.

CHAPTER FOUR.

EVALUATION AND CONCLUSION

4.1 Criticisms Against Kuhn’s Theory

Kuhn’s theory of science or his philosophy of science as seen in

his Structure of scientific Revolutions, is very controversial and has

attracted criticism of other philosophers of science. In order to

have a full grasp of Kuhn’s idea of revolution in science, one

first has o understand the concept of a paradigm. Margaret

Masterman already finds a problem with Kuhn’s paradigms: that is

the problem of the multiple definitions of a paradigm. According

to her, “Kuhn uses the term paradigm in not less than twenty-one

different senses in his book and according to her, all the senses

of in which paradigm is used are inconsistent with each other”.103

Kuhn has been accused of using the term equivocally, for Shapere,

Kuhn multiplicity of the meaning of the term paradigm or the

equivocal style in which the term is used leads to relativism. He

says of Kuhn:

103 Margaret Masterman, In Criticism and the Growth of Knowledge, Edited by Imre Lakatos and Alan Musgrave (New York: Cambridge University Press, 1970), p. 61.

But Kuhn, carried away by the logic of his notion of a paradigm,glosses over many important differences between scientificactivities classified as being of the same tradition, as well asimportant continuities between successive traditions. He is thus ledto deny, for example, that Einsteinian dynamics is an advance overNewtonian or Aristotelian dynamics in a sense more fundamental thancan consistently be extracted from his conceptual apparatus. If oneholds, without careful qualification, that the world is seen andinterpreted "through" a paradigm, or that theories are"incommensurable," or that there is "meaning variance" betweentheories, or that all statements of fact are "theory-laden," thenone may be led all too readily into relativism with regard to thedevelopment of science.104

Several critics have maintained that this free and easy

manipulation of the notion nullifies the value of his work. Again

Shapere asserts:

I have tried to show, such relativism, while it may seem to besuggested by a half-century of deeper study of discarded theories,is a logical outgrowth of conceptual confusions, in Kuhn's case owingprimarily to the use of a blanket term. For his view is made toappear convincing only by inflating the definition of “paradigm”until that term becomes so vague and ambiguous that it cannot easilybe withheld, so general that it cannot easily be applied, somysterious that it cannot help explain, and so misleading that it isa positive hindrance to the understanding of some central aspects ofscience; and then, finally, these excesses must be counterbalancedby qualifications that simply contradict them”.105

Sir Karl Popper was one of the first people to go against Kuhn’s

normal science thesis. In his work titled Normal Science and Its

104 D. Shapere, "The Structure of Scientific Revolutions," Philosophical Review,1973, p. 393.105 Ibid.

Dangers, Popper shows sympathy for the scientist who would, in

Kuhn’s world, be characterised as the normal scientist because

according to Popper he has been taught badly; he has been led in

the spirit of dogmatism and indoctrination. Unable to seek the

reasons why there is the application of theories but rather

content with the indispensible act of puzzle-solving. He also

opines that through a walk into the tunnel of history, one would

discover that history does not support Kuhn’s avocation of normal

science for just a few scientists in the history of science could

be regarded as normal in the Kuhnian sense. Also for Popper, what

Kuhn suggest is normal science is not normal at all. For Popper,

this dogmatic attitude intrinsic in Kuhn’s normal science is

dangerous “to science and to our civilization”.106

Some other philosophers have critiqued Kuhn claiming that he

simply makes “a caricature of science”.107 For John Watkins, “Kuhn

had depicted science as a series of widely spread upheavals

separated by lengthy dogmatic intervals”.108 Watkins further tries106 Karl Popper, “Normal science and its Dangers” in Criticism and the Growthof Knowledge, edited by Imre Lakatos and Alan Musgrave (London: Cambridge University Press,1970), 53.107 John Losee, A Historical Introduction to the Philosophy of Science, op.cit., p. 201.108 Ibid., p. 202

to repudiate Kuhn reliance on the history of science as

sufficient evidence for the normal science - revolutionary

science - normal science cycle. According to him counter-examples

from history in which there was the absence of the birth of a new

paradigm as well as the absence of the characteristics of normal

science as described by Kuhn already debunks this. He argues that

although Newtonianism turned into something somewhat like a

Kuhnian paradigm, no such paradigms emerged during the history of

the theory of matter. He states that “from the pre-Socratics to

the present day there has been an unending debate between

discontinuous and continuous concepts of matter, between various

atomic theories on the one hand and ether, wave and field

theories on the other”.109 Furthermore, Watkins argues that,

contrary to Kuhn’s description, it is never possible for a new

paradigm to emerge from normal science. He argues that Kuhn’s

view allows patience in the acceptance of a paradigm but then the

problem is the length of time the inventor of the paradigm will

have in formulating the rudiments of the paradigm. He says that

109 John Watkins, “Against Normal Science” In Criticism and the Growth of Knowledge,Edited by Imre Lakatos and Alan Musgrave (New York: Cambridge University Press, 1970),p. 34.

before the scientist shifts to the new paradigm, his entire

thinking would be influenced totally by the old and incompatible

paradigm.

Israel Scheffler argued that Kuhn's position on paradigm

replacement “reduces the history of science to a mere succession

of viewpoints”.110 He argues that unlike the history of

philosophical systems the history of science can be measured

against a yardstick of descriptive adequacy. He says that the

progress in science can be measured owing to the fact that

competing theories often make the same referential claims. Though

competing theories may impose different systems of

classification, often it is the same objects that are being

classified. He further argues that “Kuhn’s appeal to the gestalt

switch analogy promotes confusion between ‘seeing x’ and ‘seeing

x as something or other’”.111 It does not follow, he insists, that

because the clarifications of paradigms differ the object being

clarified must differ as well. Instead different paradigms simply

employ different methods of clarifying the same object.

110 Isreal Scheffler, Science and Subjectivity (New York: The Bobbs-MerrillInc.,1967), p. 19.111 John Losee, A Historical Introduction to the Philosophy of Science, op.cit., p. 200.

Kuhn however denies Scheffler’s claim that competing paradigms

can be measured against a yardstick of descriptive adequacy,

insisting that “there are certain standards of rationality

applicable to paradigm replacement”112. Furthermore, Scheffler

argues that in Kuhn’s theory one would sees different world from

different disciplinary matrices hence science is deprived of an

objective factual basis since data would be relative to a

particular disciplinary matrix. He asserts:

See how far we have come from the standard view. Independent andpublic controls are no more, communication has failed, the commonuniverse of things is a delusion, reality itself is made by thescientist rather than discovered by him. In place of a community ofrational men following objective procedures in the pursuit of truth,we have a set of isolated monads, within each of which belief formswithout systematic constraints. 113

Consequently a disciplinary matrix becomes more than just

constitutive of science but they are as well constitutive of

nature. This critique is however distorted since Kuhn already

argues that the world does not change with the disciplinary

matrix.

For Frederick Suppe, Kuhn's idea of scientists being locked up

within the walls of their own disciplinary matrix makes him112 Ibid.113 Isreal Scheffler, Science and Subjectivity, op.cit., p. 19.

guilty of committing himself to an antiempirical idealism. He

argues that “if ones approach to the world is only through a

disciplinary matrix which shapes and loads the data, how is it

that the world which does not depend on the matrix, exerts an

objectifying and restraining influence on what science accepts?

If science always views the world through a disciplinary matrix

on Kuhn's view, then isn’t Kuhn committed to some form of

antiemprircal idealism?”114

In his work Consolation for the Specialist, Paul Feyerabend made critical

remarks about Kuhn’s theory of science with special attack on his

evaluation of normal science. Feyerabend argues that the

undermining ideology of Kuhn’s entire work was only able to give

“comfort to the narrowminded and the most conceited kind of

specialism. It would tend to inhibit the advancement of knowledge

and it is bound to increase anti-humanitarian tendencies”.115 One

thing that enraged Feyerabend about Kuhn’s work was the mode of114 Frederick Suppe, “The Search for Philosophic Understanding of ScientificTheories” In The Structure of Scientific Theories, edited by Peter Anchinstein and David Bohm (Illinois: TheUniversity of Illinois Press, 1974), p.151.115 Paul Feyerabend, “Consolation for the Specialist” In Criticism and the Growth ofKnowledge, Edited by Imre Lakatos and Alan Musgrave (New York: Cambridge UniversityPress, 1970), p. 197.

presentation which he termed ambiguous, “he accuses Kuhn of not

making his evaluative point of view explicit so that readers can

take notice that there are also alternative points of view which

can lead to other evaluations”.116

He says that in reading Kuhn’s work he is often confronted with

the question of whether Kuhn is presenting methodological

prescriptions which informs the scientists on how to proceed; or

is it a description, void of any evaluative element, of those

activities which are generally called scientific. Kuhn's writing

he asserts is ambiguous in the sense that they are compatible

with both interpretations which he sees in the work. He likens

this sort of presentation with that of Hegel and Wittgenstein. In

a letter to Kuhn he says, as Hoyningen recounts,

What you are writing is not just history but ideology. It isideology covered up as history. And it is this bewitching way ofrepresentation to which I object the most, the fact that you takeyour readers in rather than trying to persuade them. This manner ofpresentation you share with Hegel and Wittgenstein117.

116 Hoyningen Huene, “Paul Feyerabend and Thomas Kuhn” In The Worst Enemy of Science?Essays in Memeory of Paul Feyerabend, Edited by Preston John et al. (New York: OxfordUniversity Press, 2000), p.109.117 Ibid.

Feyerabend goes further to criticise Kuhn’s normal science. First

he criticises Kuhn’s functional argument for normal science.

Kuhn, according to Feyerabend, asserts that normal science is a

necessary presupposition of revolution. This functional feature

of normal science aims at explaining that normal science is

necessary and good since it leads to revolution. Feyerabend

further says that “the persuasiveness of this functional

characterisation of normal science rests on two presuppositions,

namely that “revolutions are desirable” and that the particular

way in which normal science leads to revolution is as well

desirable”.118

Feyerabend argues that there are certain difficulties with the

functional argument. First he argues that the first difficulty is

that it is impossible that the desirability of revolutions be

founded in Kuhn’s theory. He asserts that “revolution brings

about change in a paradigm but following Kuhn’s account of that

change, it is impossible to say that they have led to something

better”.119 Feyerabend sees this impossibility because pre and

118 Ibid., p.111.119 Paul Feyerabend, “Consolation for the Specialist” op.cit., p. 202.

post-revolutionary paradigms are incommensurable as Kuhn himself

accepted. If a scientific revolution will only bring about a

change in paradigms and not an improvement then the argument for

the desirability of revolutions from Kuhn’s theory is completely

flawed.

The second difficulty is the argument that the route from normal

science to revolutionary science is desirable. According to

Feyerabend, argues that there is a better route to revolutions

than normal science. Feyerabend argues that in Kuhn’s theory,

scientists simply abandon paradigms because “they are frustrated

and not because they have any argument against the paradigm”.120

“They would simply give up when the problems of the paradigm gets

too big”.121 Feyerabend’s alternative for the route to revolution

is the alternative that the route to revolution should be through

the principle of proliferation. Through this principle, there are

competitions among theories and by way of this competition, “the

problems of a particular theory will be emphasized and

simultaneously the means for repairing or getting rid of the

120 Ibid., p. 203121 Hoyningen Huene, “Paul Feyerabend and Thomas Kuhn” op.cit., p. 111

difficulties can be seen”122. Influential to this second

difficulty is what he would identify as the anti-humanitarian

nature of Kuhn’s normal science he states,

I am sorry to say that I am quite dissatisfied with what Kuhn has tooffer… On one side he steadfastly emphasizes the dogmatic,authoritarian and narrowminded features of normal science, the factthat it lead to a temporary closing of the mind, that the scientistparticipating in it largely ceases to be an explorer but rather hestruggles to articulate and concretize the known… so that it is theindividual scientist rather than the puzzle-solving tradition, oreven some particular current theory which is tested.123

The third difficulty of the functional argument identified by

Feyerabend stems from the first two difficulties and he puts it

thus: “the suspicion that normal or mature science, as described

by Kuhn is not even a historical fact”.124 He also argued that the

changes which occur in Kuhn’s revolution cannot be regarded as

improvements. This is because Kuhn accepts the incommensurability

thesis. Consequently, “if a revolution brings about some changes,

but not some actual improvements, then revolutions are not

desirable”.125

122 Ibid.123 Paul Feyerabend, “Consolation for the Specialist” op.cit., pp. 205-206124 Ibid., p. 207.125 Stefano Gattei, Thomas Kuhn’s Linguistic Turn and the Legacy of Logical empiricism:Incommensurability, Rationality and the Search for Truth (Hampshire: Ashgate PublishingCompany, 2008) p. 65.

More so, Kuhn has been criticised for presenting an irrational

picture of science. His account of revolutions as involving

conflict between incommensurable disciplinary matrixes involves

conflicts which are only resolved by persuasion and not logical

arguments. As Feyerabend points out that the switch from one

paradigm to another happens as a result of frustration of the

scientists and not because of any logical reason. Hence Kuhn’s

account of science and scientific change becomes fundamentally

irrational; the acceptance of theories becomes subjective and is

fundamentally unempirical.

Steven Weinberg identifies his problem with Kuhn's theory with

his radically sceptical conclusions about what is accomplished in

the work of science. He says that “these conclusions make Kuhn a

hero among those who question the objective character of

scientific knowledge and who prefer to describe scientific

theories as social constructions, not so different from democracy

or baseball”.126

126 Steven Weinberg, “The Revolution That Didn’t Happen”, The New York Review ofBooks vol. XLV, no.15 (October 1998)

More so, he argues that Kuhn made the shift from one paradigm to

another look like a religious conversion rather than an exercise

of reason. Steven finds a serious problem with Kuhn’s claim to

incommensurability. That in scientific revolutions it is not only

our scientific theories that change but also the standards by

which scientific theories are judged, so that paradigms that

govern periods of normal science are incommensurable. He argues

that Kuhn's conclusions are only favourable to “those scientists

who take a more sceptical view of the pretentions of science but

wormwood to scientists who think that the task of science is to

bring us closer to objective truth”.127 Criticising the subjective

nature of Kuhn's revolutions, he asserts

If scientific theories can only be judged within the context of aparticular paradigm, then in this respect the scientific theories ofany one paradigm are not priviledged over other ways of looking atthe world such as shamanism or astrology or creationism. If thetransition from one paradigm to another cannot be judged by anyexternal standard, then perhaps it is culture rather than naturethat dictates the content of scientific theories.128

He further argues that Kuhn is false in saying that scientists

are unable to switch back and forth between ways of seeing and

that after a revolution has occurred they become incapable of

127 Ibid.128 Ibid.

understanding the science that went before it. Steven argues that

Kuhn gives attention to the paradigm shift from Newtonian

mechanics to the relativistic mechanics of Einstein but then in

teaching new physicists, the first thing they are taught is that

Newtonian mechanics, and they never forget to think in Newtonian

terms even after learning about Einstein’s theory of relativity.

Kuhn himself, Steven says, being an instructor at Harvard must

have taught Newtonian mechanics to undergraduates, hence he is

also capable of thinking in both Newtonian and Einstein terms.

Steven further argues that in his forty years of involvement in

revolutionary changes, he has never seen signs of Kuhn's

incommensurability between different paradigms. In truism “our

ideas have changed but we have continued to access our theories

in the same way: a theory is taken as a success if it is based on

simple general principles and does a good job of accounting for

experimental data in a natural way”.129Hence since there are no

changes in the way we access theories, there is not the

impossibility of comparing the truth of theories before and after

a revolution.

129 Ibid.

Kuhn's position on theory choice is has been judged to be an

unacceptable theory because it rests on much too radical claims

about the ability to translate from one paradigm to another.

Kuhn’s account of revolutions as involving conflict between

incommensurable disciplinary matrixes, which conflict can only be

resolved by persuasion and not logical argument has led

philosophers of science to charge that in Kuhn’s theory, science

and scientific change has become fundamentally irrational. Kuhn

insists that if it is true that the meaning of a scientific term

is dependent on its paradigm, then terms like energy, mass and

force used in Newtonian mechanics will have to be redefined when

used in stating the theory of relativity. The implication is that

Newton and Einstein cannot if they are brought together to

discuss the merits of their theories. J. Aronson found this

argument to be ridiculous. He argues that it is possible for

Newton and Einstein to understand each other in spite of the fact

that their laws were not identical. In his opinion, “one thing

Kuhn cannot do is argue that Newton and Einstein cannot mean the

same thing or share enough forms of life to do so, because their

theories are after all incommensurable; such a ploy would beg the

entire issue”.130

Lakatos rejects the incommensurability thesis. In a comparison of

Hume, Carnap and Popper, Watkins opines that “the growth of

science is inductive and irrational according to Hume, inductive

and rational according to Carnap, non-inductive and rational

according to Popper”.131 To this comparison, Lakatos adds that the

growth of science is non-inductive and irrational according to

Kuhn. He argues that kuhn’s view involves no forms of logic but

only a psychology of effect, the idea of a crisis is only a

psychological concept which arises from no rational cause

whatsoever. On the irrationality of scientific change in Kuhn,

Lakatos asserts:

In Kuhn’s conception, anomalies, inconsistencies always abound inscience, but in ‘normal’ periods the dominant paradigm secures apattern of growth which is eventually overthrown by a ‘crisis’.There is no particular rational cause for the appearance of akuhnian ‘crisis’. ‘Crisis’ is a psychological concept; it is acontagious panic. Then a new paradigm emerges, incommensurable withits predecessor. There are no rational arguments for their

130 Jerrold Aronson, A Realist Philosophy of Science, (London: The Macmillan PressLtd., 1984), p. 123131 Imre Lakatos, “Methodology of Scientific Research Programmes” In Criticism andthe Growth of Knowledge, edited by Imre Lakatos and Alan Musgrave (New York: CambridgeUniversity Press, 1970), p. 178.

comparison. Each paradigm contains its own standards. The crisissweeps away not only the old theories and rules but also thestandards which made us respect them. The new paradigm brings atotally new rationality. There are no super-paradigmatic standards.The change is a bandwagon effect. Thus in Kuhn’s view scientificrevolution is irrational, a matter of mob psychology132.

Similarly, Scheffler also identifies this transference from

paradigm to paradigm with ‘mob psychology, “as opposed to a

process of individual reflection that is far open to evidence”.133

In Reflections on my Critics, Kuhn rejects this description by critics of

his concept of the conversion of scientists from paradigm to

paradigm as ‘mob psychology’. Furthermore, he rejects the claim

that his account of theory growth is irrational, he states that

“to say that in matters of theory-choice, the force of logic and

observation cannot in principle be compelling is neither to

discard logic and observation nor to suggest that there are no

good reasons for favouring one theory over another”.134

132 Ibid.133 Herbert Simons, “Incommensurabilty in the Debate About KuhnianIncommensurability” In Rhetoric and Incommensurability, edited by Randy Hallen Harris (Indiana: ParlorPress, 2005), p. 250.134 Thomas Kuhn, “Reflections on my Critics” In Criticism and the Growth of Knowledge, edited by Imre Lakatos and Alan Musgrave (New York: Cambridge UniversityPress, 1970), p. 234.

More so, Kuhn’s claim that the meaning of terms varies according

to particular paradigms, thus rendering communicability

impossible between competing theories transcends to what Thomas

Dohmen calls “semantic holism”.135 In semantic holism, the sense

of a word is determined by the position of the world in a network

of meaning. Hence “if two different networks corresponding to

different theoretical frameworks contain the same word, the sense

of the word will be different”.136 Now since Kuhn

incommensurability thesis contains a linguistic problem, the

notion of translation becomes present. As Kuhn says himself “in

applying the term ‘incommensurability to theories, I had intended

only to insist that there was no common language with which both

could be fully expressed and which could therefore be in a point-

by-point comparison between them”.137 Theories are thus

incommensurable if there is variation of meaning between the

vocabulary of the theories and this variation stems from the

differences in theoretical context. And failure of translation

occurs due to the absence of a common language. 135 Thomas Dohem (2003), “Kuhn’s Incommensurability Thesis” http://www.phil.uu.nl/preprints/ckiscripties/SCRIPTIES/027_dohmen.pdf(27 March 2014), p.16136 Ibid.137 Thomas S. Kuhn, The Structure of Scientific Revolutions, op.cit., p. 189

Donald Davidson lays a ferocious attack on the idea that it is

impossible to translate between theories and on

incommensurability. He argues that if we can translate a language

into our own, then there must be an overlap in the conceptual

schemes associated with these languages. Now since there is no

reason to assume that there are languages that are untranslatable

to our own, there is also no reason to assume that there are

conceptual schemes radically different from our own”.138 Focusing

on incommensurability, Davidson presents two arguments against

the thesis. First he argues that the very idea of different

conceptual schemes is unintelligible and secondly, that we have

no reason to suspect the existence of conceptual schemes that

differ. He opines that “different points of view could only make

sense if there was a common co-ordinate systems on which to plot

them”.139 He argues further that if we associate conceptual

schemes with language, then where conceptual schemes differ, so

will their corresponding languages. However “if there is the

138 Thomas Dohmen (2003), “Kuhn’s Incommensurability Thesis”, op.cit., p. 17.139 Donald Davidson, “On the Very Idea of A Conceptual Scheme”, op.cit., p. 6

possibility of translation, there must be a shared conceptual

scheme”140

Kuhn denies the criticisms laid down by David. Contrary to

David’s claim that if something can be interpreted, then it can

be translated, Kuhn argues that interpretation is not the same as

translation. For him interpretation and translation are two

distinct processes, “translation is done by one who knows two

languages but an interpreter might only know one language and is

confronted with an unintelligible range of noises or symbols”.141

The objections laid down against Kuhn on incommensurability,

though he denies a large portion of the criticisms, led him to

make a re-evaluation of incommensurability. Hence he develops the

taxonomic incommensurability and the local incommensurability.

Furthermore, Kuhn later admits of a partial communication which

exists between disciplinary matrixes. He states that “since the

vocabularies in which they discuss such situations consist,

however, predominantly of the same terms, they must be attaching

140 Thomas Dohmen (2003), “Kuhn’s Incommensurability Thesis”, op.cit., p. 20.141 Ibid., p. 24.

some of those terms to nature differently, and their

communication is inevitably only partial”.142

4.2 Influence of Thomas Kuhn to Philosophy of Science

Undoubtedly, Thomas Kuhn had a tremendous impact on the

philosophy of science and has greatly influenced it. His

courageous turn from the tenets of logical empiricism brought

about a breakthrough in philosophy of science and developed a

different way of viewing the scientific enterprise. In the second

half of the twentieth century, “the relationship between

philosophy of science and ‘core’ philosophy experienced a radical

change so much so that it looked as though the philosophy of

science had become divorced from the rest of philosophy and had

set up home with a non-philosophical discipline, the history of

science”.143 This historical turn in the philosophy of science had

Kuhn especially to thank. Philosophers of science were no longer

concerned with questions like ‘Can we ever know any scientific

theory to be true’ but instead with questions like ‘Why do

142 Thomas S. Kuhn, The Structure of Scientific Revolutions, op.cit., p.198.143 Alexander Bird, Kuhn and the Philosophy of Science in the Twentieth Century (London:Bristol BS8 1TB, 2004), p. 2.

theories change?’ While the former may clearly be linked to

questions in general epistemology, the latter seems ambiguous

between looking for some general philosophical theory of theory-

change and a causal, historical account of theory change. At the

very least, any philosophical account of theory change would need

to be validated by reference to historical case studies.

A more influential part of Kuhn’s work is his thesis on

incommensurability. The incommensurability thesis dwells on the

incomparability of theories and Kuhn first gives three types:

semantic, methodological and observational incommensurability.

However later evaluations makes Kuhn compound a later form of the

semantic incommensurability which he terms taxonomic

incommensurability. Kuhn’s incommensurability leads him to argue

for the untranslatability of languages haven being influenced by

the work of W.V.O Quine.

However, according to Richard Grandy, “the influence of Kuhn in

philosophy of science is difficult to gauge because a great deal

of what he argued for is now taken as part of the underlying

assumptions”.144 Studying history of science, having more

realistic accounts of scientific development, and appreciating

the relevance of theories of cognition and of social processes

are all accepted and valued by the mainstream of philosophy of

science. Thus what are attributed to Kuhn are primarily the

claims about incommensurability and the dichotomous nature of

scientific change, which are the less plausible parts of his

views with the hindsight of fifty years. Kuhn’s work has achieved

a transformation of views of science that makes his most valuable

contributions invisible to many current philosophers of science.

4.3 Conclusion

Kuhn has undoubtedly influenced the intellectual attitude of

philosophy of science. With his book The Structure of Scientific Revolution,

Kuhn has been able to tamper with the rationale of scientists and

consequently brought the downfall of the results of the Vienna

Circle in the form of ‘logical positivism’. In this essay, we

have ventured to expose Kuhn’s idea of incommensurability in

which he explained that the shift which occurs in scientists144 Richard Grandy , “Kuhn, Thomas”, The Philosophy of Science: An Encyclopedia ed.Sahotra Sarkar and Jessica Pfeifer, 2006 ed., p. 430.

moving between theories is incommensurable, that is, not

measurable and therefore incompatible. Kuhn’s incommensurability

thesis stems from the progression from normal science to

revolutionary science and back to the period of normal science.

The period of normal science, Kuhn explains, involves puzzle

solving activities which engages the scientist or a particular

scientific community. According to him normal science is not

characterised by discoveries but rather puzzle solving; it is

somewhat a dogmatic period in which the paradigm which guides the

activities of the normal science is supreme and cannot be

criticised. In line with this thought, J. N Hattiangadi states

that “Kuhn portrays the normal scientist not as a thinker or as

an author of doctrine - though a scientist is that, certainly -

but as an actor of a certain kind, a technician who performs with

consummate skill”.145 The skill of the normal scientists as well

as the task which requires those skills have the same origin; the

paradigm. In Thomas Kuhn’s account of science, the birth of a

paradigm follows from a period of immature science; a state of

145 J. N Hattiangadi, “Kuhn Studies” http://www.yorku.ca/jagdish/docs/Kuhn%20Studies.pdf (8 April. 2014).

confusion in the scientific community in which the search for the

theory which will guides the scientific affairs of the community

occupies the scientists. The state of immature science can be

described in Hobbesian terms as a period of being in a state of

nature.

Kuhn helps us to know the activities which occupy scientists in

science. His ground breaking theory of science is more of a

descriptive account of the activities and growth of science. His

revolutionary science involves rational shift form one theory to

another. The origin of this shift Kuhn describes as the period of

crisis. The paradigm is hit severely by a rebellious anomaly

which threatens the veracity of the ruling paradigm this anomaly

puts the entire community in crisis and engages them in a search

for a new paradigm. Hence a revolution occurs and takes us back

to normal science.

Kuhn rejects any form of logical constructs required for a

scientists’ shift from one paradigm to another. In place of

reason, Kuhn says that idiosyncratic, subjective and

psychological feelings are paramount in the process of theory

choice. For Kuhn the transition from paradigm to paradigm

happens between incommensurable paradigms. The new paradigm is

totally incommensurable with the new one, even if terms are

borrowed from the preceding paradigm, they will have different

meanings, hence implying incommunicability between different

theories. However Kuhn later admits of the possibility of partial

communication.

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