Kuhn on Paradigm and Paradigm Change
A brief look at Kuhn’s highly influential book about scientific revolutions.
Introduction to Thomas Kuhn
Thomas Samuel Kuhn (1922–1996) was an American philosopher and historian. His book, The Structure of Scientific Revolutions (1962) has influenced how we look at theories of knowledge and sciences. It is believed that his contributions to the philosophy of science brought it closer to the history of science (by allowing reflection), and signified a break from the positivist approach to it.
Overview of The Structure of Scientific Revolutions
One of the most cited academic books, The Structure of Scientific Revolutions (SSR) is Kuhn’s attempt at challenging the prevalent logical empiricist approach to science and the development of scientific knowledge. In it, he introduced the concept of a scientific paradigm. His argument proposed that science does not (through an accumulation of knowledge) progress in a consistent and linear manner, but instead progresses within the prevalent scientific paradigm (which consists of a set of theoretical assumptions that are considered fundamental and guide the scientific inquiry and lay down the standards of ‘truth’ at that time).
Impressed and inspired by the Copernican Revolution, Kuhn came to realize how the history of (this, and other) scientific revolutions was not compatible with the commonly accepted inductivist and falsificationist approaches to scientific inquiry.
In SSR, Kuhn offers a novel approach to thinking about the scientific methodology that made a radical difference in its perception. The SSR has been considered by many to be the most influential work on the nature of rationality since Descartes’ Meditations.
On Paradigms
Kuhn has been credited with the popularization of the term ‘paradigm’, which he described as referring to ‘a collection of beliefs shared by scientists’ or ‘a set of agreements about how problems are to be understood’. In simpler words, a paradigm can be understood to refer to what the scientific community considers acceptable. Therefore, a scientific community shares a paradigm.
Criticizing Popper’s Falsificationism theory as not being compatible with the history of science, Kuhn points out how, instead of rejecting a theory/scientific system/paradigm when encountering a few anomalies, he explains (with history of science on his side) how these (few) anomalies are often ignored and how scientists continue functioning within that same paradigm.
Kuhn considered paradigms as being essential for scientific inquiry and believed that science is essentially a communal activity.
He puts forward the following two applications of the term ‘paradigm’ :
a) Disciplinary Matrix, which provides answers to the questions posed by science and provides a framework for science to operate within. This can be understood with the help of an example. Answers to questions about the nature of the things in the universe, their interactions, the constitution of evidence and solutions, and the like make up the shared beliefs of scientists.
b) Exemplars consist of all the successful components of science that the scientists work with or act on in the beginning. For example, in science textbooks, students study standard problems and their solutions and conduct experiments to reach that same accepted, standard solution demonstrated in the textbook. By repeating the experiment, it is expected that the student will use their aptitude to apply the same techniques to similar scientific problems.
On Normal Science
By Normal science, Kuhn meant to refer to the scientific research that takes place in accordance with (and is conducted within) the prevalent dominant paradigm. Most sciences are normal sciences. Also involved in this is the process of elaborating/extending the existing paradigm. Minor problems that arise within the paradigm are solved with the help of associated theories. For example, gathering information about a phenomenon and then accommodating the newly acquired information within the accepted theory.
Normal science is also known as a ‘puzzle-solving activity’ where the paradigm dictates the rules that are used for problem-solving. For example, looking for the chemical structure of familiar compounds, attempting to make more detailed predictions about planets and heavenly bodies, or mapping the DNA of particular bacteria.
Science is not an accumulation of facts: As per Kuhn, and in opposition to popular conception, science cannot be defined as the cumulative acquisition of knowledge. Instead, the scientific views of modern-day scientists have been based on those of their predecessors in the same field. Therefore, progress here comes from the steady increase in the stock of knowledge that we have pertaining to the universe.
Kuhn disagreed with the belief that there is a set of fundamental methodologies pertaining to all sciences which are reducible to physics.
Scientific terms do not have fixed meanings: At the time, it was commonly accepted in the nature of science that scientific terms have fixed/precise meanings. Kuhn disagreed. This will be explained later in the blog under the heading of ‘incommensurability’.
Scientists are conservative thinkers: Kuhn argues against this by saying that scientists, typically, are not objective and independent thinkers. They accept what they have been taught and then apply that to the problems that they face, as puzzle solvers who aim to discover what they know in advance.
Crisis and Emergence of Anomalies
Those ‘puzzles’ which appear as problems to normal science may be counter-instances to the concerned theory. This is a source of crisis. Consensus might be missing amongst the scientific community because of certain controversies, but this crisis gives rise to an essential tension in the scientific precept. Normal science strives to bring theory and fact to alignment, and acknowledging anomalies is what leads to the crisis. This crisis is an essential precondition for the development of new theories, and for paradigm change. Therefore, for scientific research, essential tension in the form of crisis is implicit. Research does not occur without stumbling upon counter-instances, which are the source of crisis.
This is where Kuhn inserts his disagreement with Popper. In such a crises (upon discovering anomalies), Popper applies his proposed principle of falsification and discards the theory. This would lead to an impact on the other theories within the paradigm. Kuhn pointed out that usually, these counter-instances/anomalies (within Normal science) are overlooked by scientists. They do not abandon the theories in question. Instead, scientists then work on strategies for saving said theories from being refuted, with the belief that these anomalies would eventually be resolved. If a paradigm has a record of being able to resolve most/all anomalies encountered, then there is a good reason to stick to it. Kuhn also points out that examining each and every anomaly is not a viable approach to science.
“The scientist who pauses to examine every anomaly he knows will seldom get any significant work done.” — Kuhn
On the accumulation of a greater number of anomalies, though, scientists start to question the fundamental principles on which the paradigm is based. This creates a way for mature science and for a new paradigm, which entails the introduction of a new scientific way of looking at the world.
The New Paradigm and Scientific Revolution
A paradigm change is called a revolution. A scientific revolution can be defined as a non-cumulative developmental episode of replacement of an older paradigm with an incompatible, new one. Such revolutions cause the scientists to come up with new observations while looking at old evidence with familiar equipment.
When a paradigm shift happens, one set of facts is replaced by a mutually exclusive one in the new paradigm for explaining the same set of data.
Kuhn said, “When a paradigm changes, the whole world changes along with it.”
Kuhn explained that upon the installation of the new paradigm, the old one (and the knowledge contained within it) is obliterated (i.e., rendered useless). This is what can be called the developmental pattern of a mature science, which occurs only after long periods of (traditional) normal science.
Kuhn claimed — “Frameworks must be lived with and explored before they could be broken.”
This new paradigm is not easily accepted by the scientific community. Novelty is a difficult concept in science, especially with respect to a paradigm change. Copernicus, Newton, and Einstein are people who can be credited with sparking such a change during their time.
Characteristics for the acceptability of a new paradigm
Kuhn lays down the following characteristics that a new paradigm has:
i) it must have a better capacity for problem-solving, and the arguments formulated within it are more significant and persuasive
ii) the new theory must be ‘neater’ (more suitable/simpler) than the previous one, as scientists, at times, reject theories/paradigms with an appeal to their individual ‘sense of aesthetics’.
Highly Individual Reasons: This can be an important factor to the acceptance of a new paradigm. It can also be the case that the new paradigm might not develop sufficiently to attract the whole scientific community’s allegiance. Kuhn claimed that the consent of the scientific community is the highest standard there is for the acceptance of a paradigm.
Lack of rational considerations: Kuhn’s understanding of the scientific enterprise has been accused by many as lacking rational consideration and being akin to ‘mob psychology’.
Incommensurability
‘Incommensurability’ refers to the lack of common measures.
Kuhn pointed out how, in the new paradigm, scientists might take items that are incommensurable with each other. The concepts and terms of the scientific theories in different paradigm are not mutually translatable. He said that scientists from different paradigms exist in ‘different universes’. For example, in the 19th century, the term ‘elections’ was used to refer to objects in a different paradigm, as opposed to its use today. Similarly, terms used in different cultures cannot be interchanged/transfered without error. Kuhn concluded that fixed/precise meanings cannot be attributed to scientific terms.
Kuhn said — “The normal-scientific tradition that emerges from a scientific revolution is not only incompatible but often actually incommensurable with that which has gone before.”
Endnote
The main contribution that Thomas Kuhn made to the philosophy of science is the replacement of its conception as the accumulation of knowledge with the idea of it consisting of long periods of normal science interrupted by radical paradigm shifts.
