Thomas Kuhn and Paradigm Shift


"In teaching others we teach ourselves"  - Proverb

Thomas Kuhn and Theory of Scientific Revolution:



Every discipline is characterized by both stability as well as change. Stability in the discipline helps it to consolidate its theories and presuppositions whereas change brings in dynamism in the discipline and allows itself to enrich, expand and evolve. Philosophers of science are often concerned with the process by way of which change-termed as conceptual change by Toulmene, takes place in the discipline of science. There are different theories –that given by Collingwood, Thomas Kuhn and Toulmene. Thus the Structure of Scientific revolution by Thomas Kuhn is basically a theory of conceptual change in the discipline of science.




What are the key concepts included in Kuhn’s Theory?

To comprehend Kuhn’s theory, one need to be very clear about two key terms or concepts. The two key terms or concepts are

i. Paradigm

ii. Revolution


How can we interpret the term Paradigm?

According to Kuhn, during a given period of time, there exists a fundamental theory in science that is accepted by the community of scientists. The scientific community, accepts the theory and are engaged in further exploration, elaboration and consolidation of the theory. New applications are searched for the theory and the community, as a whole, adheres with the fundamental theory and its validity. Kuhn considered a paradigm as a way of thinking and acting that is accepted by the community of scientists who work under the guidance and standards of the existing paradigm.

Toulmene characterize Paradigm as a ‘set of presuppositions’ or a constellation of concepts along with a set of assumptions and procedures that together constitute a paradigm or a world view.


Is Paradigm permanent or it changes?

No changes do occur in paradigm and such change accounts for the conceptual change and development of the discipline of science.


Why and How do this change takes place?

Most of the time in the discipline of science, the community researches and explore answers to their questions under the guidance of the existing paradigm that they accept. This period is considered by Kuhn as the phase of Normal Science during which the scientists are able to explore new applications of the theory and the observations are satisfactorily explained by the paradigm.

However, certain observations emerge that could not be explained by the existing paradigm. Thus certain natural phenomenon could not be explained by the pre-Copernican theory. New theories emerges and many in the community affiliate with the new theories.  A sort of tension arises between different factions of scientific community adhering to the old and the new theory. The struggle between those who adhered with the Classical Physics and Relativistic physics is an example of such a tension.

This emerging tension eventually leads to a challenge to the fundamental assumptions and outlook of the existing paradigm. A sort of revolution takes place and the old paradigm gives way to a new paradigm.


What is scientific Revolution in Kuhn Theory?

According to Kuhn when the existing paradigm fails to explain several of the observations that arises during the normal phase, there arises a phase of crisis. Need is felt for a new theory that can explain the anomalies. When such a theory emerges, sort of tension arises between those who affiliate with the older theory and the new theory. Eventually, the new theory emerges full blown and it replaces the old one. A new world view with a new set of assumptions and outlook gets established and a new era of novel questions and researches arises. This change over was termed by Kuhn as a Scientific Revolution characterized by a shift in the paradigm.

For Kuhn, scientific revolution “are here taken to be those noncumulative developmental episodes in which an older paradigm is replaced in whole or part by an incompatible new one…”

What is the significance of Kuhn’s Theory?

Kuhn provided a new approach to view conceptual change in the discipline of science and hence explain the developmental process of the discipline. It also establishes the role of community of scientists in the conceptual change that occurs in science or for that matter in any other discipline.



Conceptual change is characteristic of any discipline including that of science. According to Kuhn, the conceptual change takes place through sort of revolution that Kuhn called as scientific revolution that leads to a change in paradigm that guides the research and inquiry in the discipline. A new theory emerges that replaces the older one and is able to explain the anomalies in observation that accumulated during the normal phase of science.