The Pedagogical Implications of Parallels between Kuhn's Philosophy of Science and Piagets' Model of Cognitive Development

Submitted to Dr S. Abell
as partial requirement for EDCI 591S
by Dan MacIsaac
Wednesday, May 1, 1991


This paper was written when I was a graduate student in 1991. I have read a lot of Piaget since then and have come to appreciate more of his ideas in a different way than I did when writing this paper, but the representations of Piaget and Kuhn I make here have not been completely overturned in my mind since. The critiques section is the weakest, and I feel now that I treated Dr. Hodson's theories overly casually, so I encourage you to read his ideas in the original forms and not to rely on my portrayal of his theories or of the GLM in this paper. I hope you find the paper interesting, and you are welcome to re-cite or quote it as you see fit.

Dan M


Parallels between Kuhn's historically-grounded philosophy of science and Piaget's theory of cognitive development have been drawn by various science educators and used by some as a basis for curricular development in school science instruction. This paper will briefly review the theories in question and will offer critical comments from post-Kuhnian philosophy, cognitive psychology, sociology and evolutionary theory. Finally, the pedagogical implications of these criticisms will be discussed in light of one of the curricular methods developed as a result of Kuhnian and Piagetian thought (Hodson, 1988).
A footnote encountered by chance led me to the experiments by which Jean Piaget has illuminated both the various worlds of the growing child and the process of transition from one to the next.
-- T.S. Kuhn, Preface, The Structure of Scientific Revolutions (1962)

Introduction: Pedagogy, Philosophy and Psychology

This paper is concerned with school science instruction, and this instruction is affected by theoretical models in the philosophy of science describing how scientific research advances scientific knowledge and models in psychology and epistemology describing human learning processes. Since these fields both deal with human knowledge acquisition, it is not surprising to see related ideas and similarities in their taxonomies, and for some to draw upon them for the purposes of designing '...a philosophically more valid science curriculum' (Hodson, 1988), or a 'Generative Learning Model' (Osborne & Wittrock, 1985).

The next two sections will review the taxonomies of Kuhnian philosophy of science and Piagetian principles of genetic epistemology.

Kuhn's Model of Scientific Revolutions

Arguably the most profound work in the philosophy of science in the past fifty years has been that of Thomas Kuhn. His framework for evaluating scientific progress was a radical departure from previously accepted positivist notions of science as a steadily accumulating body of knowledge using objective observations of natural phenomena as the final arbiter of scientific theory. His historically-grounded model describes scientific disciplines as passing through five distinct stages of development; from an immature science to a normal (mature) science espousing a socially-constructed theoretical matrix or paradigm, then follows a buildup of anomalies which cannot be interpreted within the original paradigm (crisis), then a revolution brought about by groups within the community (invisible colleges) espousing various alternative paradigms and finally a reformation of the community as the new paradigm becomes the accepted norm. The tumultuous interval between widespread dissatisfaction with the original and acceptance of the new paradigms is also known under the lable of revolutionary science (see Figure 1).

The Kuhnian model emphasizes the social negotiation of meaning by the scientific community within a paradigm, and that any interpretation of observation is inseparably intertwined with the active paradigm. Cumulative scientific endeavour with the confines of a paradigm (also known as a weltanschauung or world view) defines normal science. Revolutionary science describes the research and theorizing that appear outside of the paradigm in search of explanations for those anomalies not treatable under the original paradigm and the resolution of this crises by renegotiating a new paradigm within the scientific discipline.

Kuhn further states that science is incapable of weighing merits of alternative paradigms (Kuhnian 'incommensurability') within the confines of experiment and logic; external means of evaluation must be taken during revolutionary science and the resolution of the crisis will lead to a revision (and usually a redefinition) of the entire field or discipline.

Figure 1: Kuhnian Model of Scientific Progress

Examples of Kuhnian revolutions include those of Copernicus, Newton, Lavoisier, Maxwell and Einstein; and the use of the political term revolution (dating to the Copernican paradigm shift describing a revolving earth) is intended to reflect the intense revisionary nature and upheaval inherent in a paradigm shift.

Piaget's Model of Cognitive Development

Jean Piaget's work is also recognized as being of profound import in the fields of developmental psychology and pedagogy, although he was primarily an epistemologist whose studies of the construction of knowledge led him to the investigation of human mental development. His theory of genetic epistemology (Piaget, 1972; Wadsworth, 1971) describes the constraints upon the development of knowledge in terms of cognition and cognitive development and this theory played a large role in the discard of Skinnerian behaviourism in favour of cognition as the operating paradigm in the field of psychology (Bechtel, 1988).

Piaget's model describes the mind as organizing internalized regularities (operations) into dynamic cognitive structures known as schema, which represent the relationships between perceived environmental regularities (concepts). Initially humans have only a limited number of schemata which are inborn (ie - sucking), but with living experience develop linkages and perceive relationships between concepts, developing a rich variety of schema which subsume one another and encompass different fields of endeavour and behaviour.

According to Piaget, cognitive development can proceed in one of two ways; either by assimilating a new relationship directly into the present schema by extending it to subsume the new relationship '..simple growth...' (Wadsworth, 1971), or by creating a new schema (or changing the structure of the original schema to create a different schema) by accommodation. Assimilation is said to reflect a quantitative change in mental structure (growth) while accommodation reflects a qualitative one (development). Figure 2 attempts to portray assimilation and accommodation in schema.

Figure 2: Piagetian Assimilation and Accommodation in Schema

The balance between accommodation and assimilation is known as equilibrium, and the constant inborn drive of the human mind to assimilate new information will periodically result in a condition of imbalance termed disequilibrium or cognitive dissonance. Disequilibrium is resolved through combinations of accommodation and assimilation which modify schemata appropriately for the persons' needs.

These processes of assimilation and accommodation continue throughout human life, although some underlying schemata are tied to biological development and create a series of developmental cognitive stages related to maturation. Assimilation and accommodation in response to disequilibria account for all cognitive growth and development, and therefore shape human learning.


Needless to say, there are some striking similarities between Kuhnian science philosophy and Piagetian genetic epistemology -- patterns of seemingly straightforward, cumulative growth followed by unrest and rapid reorganization into a slightly different pattern of cumulative growth (Figure 3). This has led to the idea of instruction recapitulating philosophy within science education (Hodson, 1988; Osborne & Wittrock, 1985) through the artificial creation of a Kuhnian revolution and/or a Piagetian accommodation in the minds of students in the classroom.

Figure 3: Parallels between Genetic Epistemology and Kuhnian Science

However, how cogent are these comparisons? This section will examine those elements from each field resembling one another and will comment upon the appropriateness of relating these elements.

Immature Science and Operations

Kuhn describes scientific disciplines as commencing from a variety of schools of ad hoc thought known as immature science. These proto-scientific activities are described by Kuhn as '..something less than science. Being able to take no common belief for granted, each writer...felt forced to build his field anew from its foundations'. No common body of belief could be taken for granted by practitioners of immature science because each investigator held widely discrepant views on their subject.

Examples of immature science taken from early electrical science include the work of Hauksbee, Gray, Desaguliers, Du Fay, Watson, Franklin and others, each of whom were major figures in their day and each of whom proposed conflicting theoretical bases for their studies. Others involved in immature science include Bacon, Plato, Epicurus, Aristotle, chemical practitioners before Boyle (the alchemists), and optical experimenters before Newton. Kuhn also suggests that geological and biological science have only recently emerged from immaturity and that much of current social science is still immature (Kuhn, 1972).

Piagetian operations refer to a series of nonisolated cognitive precursors required for development, and exemplified by the famous Piagetian operations of spatial coordination, correspondences, different varieties of conservation, classifications, etc. Children's development is regulated by the presence and development of these structures, which are internal and unique to the individual. The development of these structures is dependent upon the internalization of behaviours and actions within the mind of the child; '...actions lead to the development of operations, and operations in turn lead to the development of [schema]' (Wadsworth, 1971).

Paradigms and Schemas

Kuhnian paradigms characterize periods of normal, cumulative scientific growth and define the acceptability (and worthwhileness) of different research and theoretical practise. Paradigms are used to determine relevance '...without a paradigm, all possible facts seem equally relevant ', and demonstrate maturity within a discipline '...acquisition of a Paradigm is a sign of maturity' (Kuhn, 1972). Paradigms encompass theory and practise within disciplines '...implicit body of intertwined theoretical and methodological belief that permits selection, evaluation and criticism', and have 'predictive power' (ibid). Paradigms are socially negotiated constructs, although initially dependant largely on the work of a single individual.

Piaget's schema (or schemata) are internal cognitive structures subsuming complex behavioural patterns (Flavell, 1963), and have been described as the mental counterparts of biological means of adapting to and surviving in the environment . Schemas change and adapt with mental development, and as human development progresses, an individuals' schemata become broader, richer and more differentiated. More individual schema are created to deal with a great number of different situations, and these schema are continuously refined. An individual schema '...coordinated with all other schemata and itself constitutes a totality with differentiated parts...' (Wadsworth, 1971).

Piaget himself refers to Kuhnian paradigms as belonging within 'Our notion of epistemic framework...', which describes ' explanatory schema for the interpretation of the evolution of knowledge, both at the level of the individual and that of social evolution'. He further recognizes the role of social construction in schemata, stating '...when language becomes the dominating means of communication...what we might call direct experience of objects becomes subordinated the system of interpretations attributed to it by the social environment' (Piaget, 1988).

However, he believes that his notion of epistemic framework '...includes that of paradigm...but is simply different' (ibid). Paradigm belongs to the sociology of knowledge rather than with epistemology (concerned with the acquisition of knowledge).

Normal Science and Assimilation

Kuhn describes normal science performed within the confines of a paradigm as the 'Mopping-up operations...[which]...engage most scientists throughout their careers' or as 'puzzle-solving'. Paradigms define 'classes of facts to be particularly revealing'; therefore these are worth determining with more precision and in a variety of situations (Kuhn, 1972).

The performance of normal science elucidates, extends and confirms paradigms, and the accepted disciplinary paradigm is so ascendant that a scientists' failure to solve one of these 'puzzles' is usually considered a personal failure, and not one of the the theory. Only with grossly overt, repeated, large-scale failure does the paradigm ever become the object of discussion. Clearly normal science is a socially-mediated, cumulative, harmonious extension of the current paradigm.

Piagetian assimilation (a term itself borrowed from biology) is described as the cognitive counterpart of biological feeding in which new events are fit into existing schema. Assimilation is also compared to the growth of a balloon through inflation (Wadsworth, 1971).

According to Wadsworth (1978), '..the child's active assimilation of objects and events results in the development of structures (schemata) that reflect the childs' concepts of the world or reality. As the child develops these structures, reality or his knowledge of the world changes.' However, schema are not directly derived from raw objects and events, but from operations.

While schema are the highest-order mental organizations, schema never appear alone; structures are always related to other structures and many structures are substructures of larger structures (Wadsworth, 1978). Comparisons between Kuhnian normal science and Piagetian assimilation reveal that assimilation is a much more complex and fluid activity. There is a great deal of flexibility displayed within assimilation, while normal science is rigidly constrained.

Crises and Disequilibrium

Periodically, Kuhnian science undergoes crises as significant numbers of the scientific community express misgivings or dissatisfaction with their paradigms' failure to account for anomalous phenomena. Such anomalies that challenge the current paradigm and precipitate crises are called scientific discoveries by Kuhn, with the intent of describing an aberrant phenomena uncovered by the discoverer. Some such scientific discoveries of aberrant phenomena include X-Rays, elemental oxygen and the Leyden jar.

Crises itself is achieved when widespread dissatisfaction in the scientific community leads to the emergence of multiple alternative theories emerge that provide modified or alternative paradigms capable of treating some aspects of the new discoveries. 'By the time Lavoisier began his experiments on airs in the early 1770's, there were almost as many versions of the phlogiston theory as there were pneumatic chemists' (Kuhn, 1972).

The resolution of these crises in scientific research can only be had through the competition of these new alternative theories to become the new paradigm. In the absence of new paradigms, no amount of dissatisfaction can lead to a resolution. Kuhn states 'Once a first paradigm through which to view nature has been found, there is no such thing as research in the absence of any paradigm. To reject one paradigm without simultaneously substituting another is to reject science itself' (ibid).

Kuhn provides an example of this kind of crisis in physics through quotations from Wolfgang Pauli: 'At the moment physics is again terribly confused. In any case, it is too difficult for me, and I wish I had been a movie comedian or something of the sort and had never heard of physics.' After Heisenbergs' Uncertainty Principle (an alternative paradigm) had been published, Pauli was quoted 'Heisenberg's type of mechanics has again given me hope and joy in life. To be sure it does not supply the solution to the riddle, but I believe it is again possible to march forward.' (Kuhn, 1972). Piagetian disequilibrium is an internal state experienced by individuals having competence (extensive schemata) resulting from a perception of a discrepancy within their own schemata.

Disequilibrium can also be described as the intrinsic motivation for a child to modify their own cognitive structures to a 'better' adaptation -- that is one that is internally consistent. The mechanism resides within the child, and 'materials or events do not have the capacity to create disequilibrium in themselves' (Wadsworth, 1978).

Obviously, children are rarely in complete equilibrium in any single developed schemata, but each disequilibrium always progresses in the 'correct' direction -- 'that which is most like those perceived as [external] reality, because of the nature of the objects on which the child acts, as well as the nature of the social environment'. Piaget even goes so far as to state that teachers have no need to be concerned with the direction or outcome of disequilibrium, nor can teachers ensure generating or hope to control the process (ibid).

Revolutionary Science and Accommodation

The final stage of Kuhnian science is the succession of a new paradigm to the accepted norm, complete with a redefinition and reorganization of the entire discipline, and the scientific revolutions accomplishing is central to his theory. Out of date theories become viewed as special cases of the new paradigm or are discarded. With the change of paradigms come '...significant shifts in the criteria determining the legitimacy both of problems and of proposed solutions'. The final judge of worth during the competition of alternative paradigms is one of 'future promise', and the decision itself 'rests only upon faith' (Kuhn, 1972).

Kuhnian revolutionary science occurs in an atmosphere of incommensurability; advocates of competing paradigms cannot resort to logic or proof when defending their world views. Differing advocates simply practise their trades in different worlds. This makes individual scientists unlikely to endure the change of paradigms inherent in a scientific revolution, leading to Plank's observation that 'a new science does not triumph by convincing its opponents and making them see the light, but rather because its opponents eventually die, and a new generation grows up that is familiar with it' (ibid).

Piagetian accommodation seems a much less traumatic and more peripheral phenomenon in the theory of genetic epistemology -- it is portrayed as an extension of assimilation, a reshuffling of cognitive structure in an attempt a harmonizing the whole. It is a continuous process (like assimilation), hardly a radical internal change; but it may be evidenced by radically new behaviours which are consistent with the new internal structures (Cellérier, 1987).

Accommodation is a stabilizing force and does constitute a discontinuity , but according to Piaget, '...the changes in structure are not merely leaps in a vacuum; they follow an internal logic which has been documented in psychogenic research... On this point we take a position which is opposed not only to that of Kuhn and Feyerabend...' (Piaget & Garcia, 1988). Accommodation is a continuous, unremarkable, internal, epistemological activity.


There are several noteworthy points that can be seen from our comparisons; Piagets' theory of genetic epistemology is a biological description of a childs' internal and individual mental development, while Kuhn writes of an overt, negotiated societal development portrayed in historical contexts. While there are many parallels between the taxonomies of the models, they are applied in different domains, and describe wholly different phenomena. At best they describe widely disparate aspects of related phenomena. In overall tone, Kuhn's model seems much more rigid and incomplete than that of Piaget, which reflects the great depth and clarity of Piagets' descriptions. Piagets' epistemological writings are clearly those of a noninterventionist researcher and commentator, while Kuhn is a political historian who describes pedagogy as a revisionary tool for the indoctrination of individuals into paradigms.

Analysis of the theories of Piaget and Kuhn in terms of pedagogy must recognize Kuhn's contributions to the sociology of science, but does not in the whole support implementation of either theory as pedagogical models. To exploit Kuhn's theory outside of its intended domain is inappropriate. Even Piaget's theory (while exerting profound influences upon instructional styles) is not designed as a interventionary guide for instruction; he specifically disparaged any attempt to overtly train children in either Piagetian operations or to accelerate student development through his stages of cognitive maturation (this would be akin to attempting to encourage biological evolution in living organisms).


We shall now examine extensions, revisions and critiques of Kuhnian and Piagetian theory relevant to pedagogy that have emerged from the philosophy of science, cognitive psychology, sociology and evolutionary theory.

Post-Kuhnian Science Philosophy

Much has been made of the arbitrariness of Kuhn's paradigmic transition. Kuhnian pedagogical changes are '...mediated only by extra rational means, which undermines the validity of science as a rational enterprise' (Bechtel, 1988). His only suggested criteria for the evaluation of paradigms are their 'future promise' and faith. The Kuhnian model seems incomplete.

Post-Kuhnian science sociologists such as Lakatos and Laudan (Bechtel, 1988; Giere, 1988) suggest that the central role of discontinuity inherent in the Kuhnian model mistakenly portrays science as an irrational process at heart. They suggest that no single scientific world view exists, replacing the Kuhnian notion of paradigm with the terms research programme or research tradition. Such Lakatosian research programmes consist of a hard core of basic assumptions shared by all investigators, surrounded by a protective belt of auxiliary assumptions, finally surrounded by experimental observation. Laudan's research traditions lack even the hard core immune to revision; for him the solution of problems by familiar needs organizes all science.

Cognitive Psychology

Cognitive psychology analyzes human thought by modelling the mind as an information-processing machine. This model has resulted from a large body of research upon computer knowledge and has led to much psychological and pedagogical insight, but has sharply limited ability to predict human behaviour and learning nonetheless. Cognitive theory describes memory storage and recall structures resembling Piaget's schema and describes regular inclusions and revisions to these structures similar to Piagetian assimilation and accommodation.

Cognitive development is considered highly dependent upon cognitive precursors, similar to Piagetian operations and Kuhn's emergent scientific theories. However, the great discontinuities inherent within Kuhnian revolutions based upon extra-rational decisions are not possible according to cognitive theory. Internal development is gradual and self-consistent at all times, and even though seemingly disparate external behaviour is occasionally evident it is actually mandated by a continuous cognitive development (Bechtel, 1988).


Another major critique of Kuhnian theory rests with its' apparent lack of recognition of pressures placed upon the scientific community by external society. Kuhnian change is mandated only by forces from within the scientific community, while other historical analyses have shown this is untrue (Garcia, 1988). Kuhn suggests that a defining characteristic of a mature science is its isolation from the world external to the paradigm of the community, while Garcia points out that science is shaped by both sociological forces and the sociogenesis of knowledge itself (Piaget & Garcia, 1988).

Garcia suggests that the political and social climates prevalent in France, Germany and England during the 17th and 18th centuries were primary factors in the different forms of scientific development that occurred in those countries. He goes on to state that small changes in societal attitudes (akin to cognitive precursors) were responsible for major changes in energy theory in physics during that time as well. Certainly there are major instances today of societal impact upon scientific endeavour; the impact of the Manhattan Project during the second world war upon nuclear physics, the impact of the cold war upon space science and western science education in general, of the environmental movement upon recent nuclear physics and fusion research and the impact of societal expectations upon recent biological, medical and reproductive technologies. All of these describe how societies shape the science that is being performed. The list of examples seems unending.

Evolutionary Theory

Piaget describes genetic epistemology from the viewpoint of biological evolution. This has led to a reexamination of Piagetian equilibrium in terms of evolutionary theory. Cellérier (1987) states that '...schemes like genes, compete for control of the activity and evolution of the system in which they cohabit and participate'. This means that knowledge appears, 'evolves' genetic descendents in the system, and eventually disappears and this continuing process constitutes the evolution of the system.

This would indicate that there is no permanent or fixed knowledge in the mind, a continuous evolution tests, reinforces, updates and discards schemas. New concepts must run a constant gamut of competition before incorporation into resident schemas, accounting for both assimilation and accommodation at the same time. Cycles of generation and selection would also indicate a more gradual transition in individual knowledge than seen in the Kuhnian revolution, and reinforces a need for cognitive precursors. According to evolutionary theory, adaptation to both the external environment and to the existing internal epistemic environment within the mind would form the evaluative criteria for cognitive development. This counters Kuhnian revolutionary theory, which uses faith and 'future promise' evaluated by the scientific community as discriminants in the large scale discard and redefinition of paradigms.

Implications for Pedagogy

These comments have considerable import upon the implementation of pedagogical models embodying the re-creation of Kuhnian science in the classroom. They suggest that some aspects of such an endeavour are highly appropriate, while others are not. Stepping through one such model, that of Hodson (1988) we see a commitment to the negotiation of meaning and to the refinement of ideas, implications and views through commonly held and interpreted experiences, all of which would contribute to the establishment and development of rich schema. There is almost universal acceptance that these are desirable classroom activities.

Hodson's model further suggests that having established a socially negotiated paradigm or schema, teachers should introduce experiences designed to contradict and challenge their existing views (trying to duplicate Kuhnian scientific discoveries or to induce Piagetian disequilibrium). We have already discussed the inability of teachers to ensure the creation of disequilibrium and to control this event. Many students will not recognize the aberrant phenomena as being anomalous, and we are all familiar with students learning 'school science', a series of unusual beliefs and practises that hold true in school laboratories but are not part of the world views of the student. In fact, it could be argued that repeated exposure to laboratory anomalies (especially those using specialized apparatus specifically designed for demonstrating a particular phenomena) is counterproductive as it removes these from the ordinary experience of children.

Piagetian genetic epistemology does not place any greater value upon accommodation than on assimilation, and further suggests that any rich, interesting environment full of varied stimuli will be assimilated and accommodated by children continuously. Gross anomaly cannot possibly be recognized without student subject matter competence (a well developed schema) and therefore teachers should not expect to regularly teach new subject material and then present anomalies to illuminate this material. This is not to say that varied stimuli and discrepant events should not be regularly present in the curriculum, but that teachers should expect no reproducible results or effects from any single situation.

Hodson also suggests that students 'brainstorm' in an attempt to create new or alternative paradigms or theories to explain the anomalies, then negotiate their personal interpretations communally. Again, while communal negotiation is extremely desirable activity, it is unlikely that students can generate appropriate, viable explanations and theories without an intimate knowledge and well-developed schema regarding the subject matter itself. Students are either doomed to failure or to trivial practises as they 'rediscover' the obvious in an effort to please their instructor. Considering the difficulties that arise in the scientific community with the emergence of new scientific theory and the low ability of trained, professional scientists to change paradigms at all it is unlikely that we can expect such activity in any school activities.

Hodson further avoids several real issues when suggesting that teachers should proffer the currently accepted explanations of anomalous events as one of the new alternative paradigms open for classroom debate. Students may seize upon the teachers' explanation as the obviously correct one and their own efforts as a trivial game. Or they may choose an alternative interpretation as the agreed upon paradigm, leaving the teacher in the dilemma of having not taught the 'correct answer'. Hodson does not describe what is to be done in this case, but Piaget provides a clearcut answer: do nothing. Any changes in student understanding are temporary at best, and are automatically for the better; the 'right answer' is hardly the issue in Piagetian epistemology, and should not detract from the developmental process at all.

Finally, Hodson's model is notably absent in any recognition of the role played in scientific research by societal values -- he refers to such activity as peripheral or 'interdisciplinary'. Kuhn's science is also an isolated enterprise occurring in a small community outside the norm, affected to small degree by outside influence. Piaget, Garcia and many others have made an eloquent case that this is a clearly inappropriate interpretation of how science is done and how societal roles in science are shaped. If we agree that educating all children in scientific disciplines regardless of whether they become professional scientists is worthwhile, then we must expect that these children will take a decisive role in the scientific ethos of their own societies.

In closure, it seems apparent that the Kuhnian model of scientific revolutions is best taught as what it is: an effort to historically analyze and report the scientific enterprise. It is a sociological examination. Piagets' theories are an epistemological examination of how human beings come to know that which they do know, and also therefore should be taught as what it is: an examination of how we construct knowledge. Science pedagogy requires close understanding of both of these topics, but deals in a world foreign to both Piaget and Kuhn; one where adults regularly intervene into childrens activities in an attempt to pass along attitudes and information.


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