Thomas S. Kuhn

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Thomas Samuel Kuhn (born July 18, 1922 in Cincinnati , Ohio , † June 17, 1996 in Cambridge , Massachusetts ) was an American physicist , philosopher of science and science historian . He is one of the most important scientific theorists of the 20th century.

In his main work, The Structure of Scientific Revolutions , Kuhn describes science as a sequence of phases in normal science, interrupted by scientific revolutions. A central concept here is the paradigm ; a paradigm shift is a revolution. Kuhn describes the relationship between paradigms between which a revolution lies as incommensurable , which means here: not measurable with the same (conceptual) measure.


Thomas Kuhn was born in Cincinnati in 1922 to a non-practicing Jewish family. His father worked as an engineer in industry and his mother as a proofreader. In 1940 he began studying physics at Harvard University , where his father had already studied . During his studies, he took several courses in philosophy and literature and also wrote for the student newspaper Harvard Crimson .

After his bachelor's degree in 1943, he first worked in a radar research laboratory ( Radio Research Laboratory ) at Harvard. There he was involved as theoretician in radar countermeasures for the Second World War . In 1944 he was employed as a radar technician in Great Britain and in northern France, which had just been conquered by the Western Allies. In the autumn of 1944, Thomas Kuhn returned to Harvard, where he continued his studies: He received his master's degree and received his doctorate in theoretical solid-state physics in 1949 under the later Nobel Prize winner John H. van Vleck .

At that time his real mentor was the then President of Harvard, James Bryant Conant . Conant became aware of Kuhn because of his unusual involvement for a physicist at Harvard Crimson and in a literary-philosophical club. At Conant's initiative, Kuhn gave a course in the history of science even before completing his doctorate . The work on this course strongly influenced Kuhn, so that he decided against physics and a career as a historian and philosopher.

Proposed by Conant, Kuhn became a member of the Society of Fellows at Harvard. There he dealt with the history of science, but was always interested in its effects on philosophy.

In 1956, Kuhn accepted a position as assistant professor for the theory of science and the history of science at Berkeley , and a few years later he became a full professor for the history of science. In Berkeley he wrote his major work, The Structure of Scientific Revolutions, among other things .

The book - he himself calls it an essay - he wrote initially as part of the International Encyclopedia of Unified Science . The impetus was the “almost unknown monograph” created in Basel in 1935, the creation and development of a scientific fact by the Polish microbiologist Ludwik Fleck , which anticipates some of his thoughts.

In 1963 Kuhn was elected to the American Academy of Arts and Sciences , 1974 to the American Philosophical Society , 1979 to the National Academy of Sciences and in 1990 as a corresponding member of the British Academy . From 1964 to 1979 he taught at Princeton University . He then moved to the Massachusetts Institute of Technology (MIT), where he held the Laurance S. Rockefeller Professorship for Philosophy, which he held until his retirement in 1991.

In 1979 Kuhn was elected a member of the Leopoldina . In 1982 Kuhn was awarded the George Sarton Medal , the highly prestigious prize for the history of science from the History of Science Society (HSS) founded by George Sarton and Lawrence Joseph Henderson .

Kuhn had been married since 1948. The marriage had three children. After the divorce in 1979, there was another marriage in 1982. He died of cancer in 1996 at the age of 73. By his death, he had completed an expanded version of his ideas on the theory of science under the title "The Plurality of Worlds: An Evolutionary Theory of Scientific Discovery" to about two-thirds. Shortly before his death, he commissioned the two philosophers John Haugeland (died 2010) and James Conant (a grandson of the aforementioned James Bryant Conant) to publish the book, but this has not happened to this day.


Kuhn's concept of paradigm

The concept of the paradigm is a central element of Kuhn's philosophy. While he used it in The Structure of Scientific Revolutions very freely and in different meanings, Kuhn tried to clarify the term in later publications.

Kuhn adopted the term paradigm from linguistics for his theory (see paradigm (linguistics) ). In Kuhn's original use, paradigms are “ concrete solutions to problems that the professional world has accepted ”. This includes examples such as solving the problem of how a ball rolls down on an inclined plane . The solutions to such problems are explained to students in textbooks. Such generally accepted problem solutions serve as a guide to solve other problems by analogizing them with the problems that have already been solved.

In The Structure of Scientific Revolutions , paradigms also take on a global meaning: Almost everything about which there is consensus in science is paradigmatic. According to this expansion of the term, entire theories can also be paradigmatic. In the following years Kuhn was often criticized for this philosophically not unproblematic softening of the concept of paradigm. However, the generality of the concept of paradigm is intended by Kuhn. In this way, in contrast to Karl Popper , he avoids the methodological determination of what science is or should be. This definition takes place within the framework of the paradigm itself. This makes the distinction between science and metaphysics as well as between the context of discovery and the context of justification obsolete.

At the beginning of the 1970s, Kuhn changed its terminology. He now called paradigms in the broad sense a disciplinary matrix , while from then on he called concrete problem solutions exemplary (although Kuhn abandoned the concept of the disciplinary matrix in the course of the 1970s). In the postscript to Structure from 1969 it says on the concept of paradigm:

“On the one hand, it stands for the whole constellation of opinions, values, methods etc. that are shared by the members of a given community. On the other hand, it describes an element in this constellation, the concrete problem solutions which, used as role models or examples, can replace explicit rules as the basis for solving the other problems of 'normal science'. "

- Thomas Kuhn, 1981 (1969)

He rarely used the terms paradigm and paradigm shift . In the meantime, they had been used both in reception and by Kuhn himself, very early on, in a broader sense, deviating from the original literal meaning of a model, imprecisely for everything that is handed down and on which there was consensus among working scientists.

Pre-paradigmatic science

For Kuhn, the existence of a paradigm is a sign of mature science, but it is not a necessary criterion for science. Kuhn also calls pre-paradigmatic science protoscience .

In the absence of recognized examples, researchers in a pre-paradigmatic phase of science have a great deal of freedom in their choice of experiments, so that scientists investigate very different aspects of their subject area and the theoretical approaches found in this way are unable to explain the experiments of other researchers.

This often creates many competing and incompatible views among scientists. Kuhn cites electricity as an example , which was explained by frictional phenomena or natural repulsion and attraction and viewed by others as a liquid before a paradigmatic theory of electricity arose in Benjamin Franklin's time .

While mathematics has had a paradigmatic character since ancient times, according to Kuhn other areas of science such as genetics have only been paradigmatic for a relatively short time. Still other areas, especially in the social sciences , are still in a pre-paradigmatic state.

Normal science

Normal Subjects referred to in the scientific theoretical concept of Kuhn one of the two possible phases of scientific development, after a science has left the vorparadigmatische phase behind. A distinction is made between the extraordinary or revolutionary phase.

Typical of normal science is the acceptance of a paradigm by the scientific community , on the basis of which research is carried out. On the one hand, the range of relevant problems is drastically limited by the paradigm, but on the other hand this means the possibility of doing in-depth research.

The task of the scientist in normal scientific phases is to solve problems, the rules of which are implicitly given by the paradigm. Kuhn describes this activity as solving puzzles , in analogy to puzzles or chess problems, in which the basic rules are fixed. Problems are preferably approached as puzzles, of which it is assumed that a solution exists for them and can also be found with the help of the solution rules. If this is not the case, problems are often rejected as metaphysical .

There are essentially three types of puzzles:

  • Determination of significant facts
This means e.g. B. the determination of the spectra of molecules or wavelengths.
  • mutual adjustment of facts and theory
This includes the elimination of inaccuracies by including in the idealized theory neglected phenomena such as air resistance or friction and on the other hand confirming experiments such as Atwood's fall machine or huge detectors for the detection of neutrinos .
  • Articulation of the paradigm
This includes the elimination of remaining ambiguities in the theory, attempts at a logically convincing presentation of a theory and the derivation of new laws from the paradigm theory.

Other normal science activities that fall under these points are the determination of universal physical constants , the formulation of quantitative laws, prime examples for the solution of scientific problems and the incorporation of new phenomena into the paradigm.

In principle, the researcher is not interested in checking or falsifying the paradigm. There is consensus on this among scientists. The goal of normal science is not fundamental innovations that could overturn the worldview, but the gradual improvement of theories within the framework of the given paradigm.

In no case does Kuhn see normal science research as a routine activity that is not very challenging. Similar to many constructed puzzles , creativity is required as well as the ability to apply methods at a high technical or abstract-mathematical level. In addition, innovations also occur within normal science, but these do not affect the basic pillars of the theory.

If problems arise in solving the puzzles, in most cases they are attributed to the poor quality of the scientist or the available experimental methods. This close connection of scientific practice to the paradigm achieves a specialization and depth that would not be possible without trust in a secure basis.

In contrast to the falsifiability proposed by Karl Popper , Kuhn considers the possibility of doing normal science to be the decisive criterion for differentiating it from pre-scientific or pseudo-scientific theories.

Kuhn describes the paradigm as the carrier of a scientific theory:

[A paradigm works] by giving the scientist knowledge of the entities which nature contains or does not contain and the way in which these entities behave. This information creates a plan, the details of which are explained through mature scientific research. And since nature is far too complex and diverse to be explored by chance, this plan is just as important for the continuous advancement of science as observation and experiment.

Scientific revolutions

Duck or rabbit? Kuhn used this known optical illusion of Jastrow to illustrate that radically changes the perception of scientists in scientific revolutions.

The phase of extraordinary science only begins when problems have arisen in central locations over a longer period of time or surprising discoveries have been made. In it, the basics themselves are discussed again. Such a crisis can lead to a paradigm shift in which one paradigm of discipline is discarded and replaced by another.

Examples of scientific revolutions cited by Kuhn include the replacement of phlogiston theory by Lavoisier's oxygen chemistry, Einstein's theory of relativity , which replaced classical Newtonian physics, and, in particular, the Copernican turn from the geocentric to the heliocentric worldview . In contrast to normal science, the increase in knowledge is now not cumulative, since important parts of the old theory are abandoned. The content of the post-revolutionary theory cannot be foreseen beforehand.

According to Kuhn, scientific revolutions change not only theories, but also the general worldview and scientific practice. This led Kuhn to repeatedly speak in Structure that it is as if it is not human interpretation but the world itself that is changing. One paradigm has an impact on deeper levels: it even affects the perception of scientists. Precursors to this claim are Ludwik Fleck (Origin and Development of a Scientific Fact) , who already called for the paradigm shift, and Norwood Russell Hanson (Patterns of discovery) . Because of the cognitive dimension of paradigms, Kuhn compares paradigm changes with so-called gestalt changes . This marks a sudden change from one perception to another.

It [the paradigm shift], like the shape shift, must happen all at once (though not necessarily in an instant) or not at all.

In the explicitly formulated opposition to Karl Popper's falsification approach, Kuhn claims that paradigms are not just given up because they have been falsified. A paradigm is only abandoned when it can be replaced by another. For the scientific community to abandon the paradigm with no replacement, Kuhn said it would mean abandoning scientific activity per se. Nor can evidence decide between two theories competing for paradigm dominance. Kuhn claims that at the time of the invention of the Copernican system there was no evidence that this system raised above the then established Ptolemaic system . This argument is known today as the underdetermination of theories by evidence and is used in particular by empiricists such as Bas van Fraassen .


One of the most controversial and most discussed points of Kuhn's philosophy is the concept of incommensurability based on an analogy with mathematics , which he introduced into the philosophy of science independently of, but around the same time as, Paul Feyerabend (Kuhn's and Feyerabend's terms of incommensurability differ somewhat from one another) . Kuhn's concept of incommensurability contains the following, at first glance heterogeneous elements:

  • The paradigms offer solutions to different problems. The focus on what is to be seen as a problem to be solved by science changes here.
  • Even if the vocabulary often stays the same, the terms that denote the words change more or less radically. In addition, some terms are no longer used at all and new ones are introduced.
  • Followers of competing paradigms operate in different worlds . Kuhn is aware that this statement is very difficult to understand. Is it only meant metaphorically? Kuhn worked to clarify this question until the end of his life and came to the conclusion that one must somehow understand this way of speaking literally.

In fact, for Kuhn, these three elements form a unit: At its core, incommensurability is the result of a conceptual change.

For Kuhn, a central example of the incommensurability of two theories is the theory of the solar system. The Ptolemaic worldview knew the following “planets”: Sun, Moon, Mercury, Venus, Mars, Jupiter, Saturn (Uranus, Neptune and Pluto were still unknown at that time). Planets were the wandering stars that moved relative to the fixed stars. In the Copernican view of the world, on the other hand, a different set of celestial bodies operates as “planets”, namely Mercury, Venus, Earth, Mars, Jupiter and Saturn. Now planets were celestial bodies orbiting the sun. In addition , two new categories are introduced, namely the sun as a central star and the satellite category, which includes the earth's moon and later the moons of Jupiter, discovered by Galileo . As a consequence, for Kuhn, surprisingly, the following applies: The sentence "In the Ptolemaic system the planets rotate around the earth and in the Copernican system around the sun" is not a really meaningful sentence, as there is no uniform concept of planets that is used in this sentence could.

As a further example, Kuhn cites the revolution from Newtonian physics to Einstein's theory of relativity . Both theories are incommensurable because words used in both theories such as B. Energy would have different meanings in both theories. Accordingly, Newtonian physics cannot be seen as an approximation to the special theory of relativity for speeds that are small compared to the speed of light. A smooth transition from one teaching to the other is therefore not possible. This is completely compatible with the correspondence principle in Bohr's sense: It is not disputed that the numerical values ​​of certain variables merge into one another at the limit crossing; that is a mathematical fact. Nevertheless, as already emphasized by Bohr for the analogous case of the relationship between classical mechanics and quantum mechanics, there remains a conceptual break between the two theories.

The hypothesis of incommensurability gives Kuhn's view of scientific development its real explosiveness. The assumption of incommensurability is directed against the idea that scientific progress is to be understood cumulatively: as a steady accumulation of scientific knowledge without significant withdrawals and breaks. This was, for example, Karl Popper's view. But Kuhn never claimed that the development of science is irrational. He only denied that the traditional view of the rational comparison of theories was appropriate, namely by making a point-by-point comparison of the various consequences of the theories involved. In fact, Kuhn has often been mistakenly understood as if he wanted to deny the possibility of a rational comparison of theories and thus the rationality of the development of science because of the incommensurability.


In the first years after Structure , Kuhn's concept of paradigm was at the center of criticism. Kuhn has often been criticized for the vagueness of his concept of paradigm. Margaret Masterman found 21 different uses of the term in The Structure of Scientific Revolutions , whereupon Kuhn made an attempt to clarify (see above ). In later decades, the criticism increasingly shifted to Kuhn's idea of ​​incommensurability.

Criticism from Lakatos

According to one of Kuhn's main critic, the scientific theorist Imre Lakatos , paradigms encompass more than one guiding principle; they are complex in their composition. They include a so-called hard core, which consists of the supporting theories (a scientific discipline, for example), as well as a “protective zone” of auxiliary hypotheses that shield the “hard core” from refutations.

According to Lakatos, the third component of the paradigms is a powerful problem-solving apparatus that belongs specifically to this “hard core” or is induced by it. Therefore, the term paradigm should be replaced by the more appropriate formulation methodology of scientific research programs. According to Lakatos, different research programs can be compared rationally and are not incommensurable.

With this, Lakatos turned against Kuhn's idea of ​​scientific revolutions and especially against the influence of social and cognitive factors on them. He accused Kuhn in clear terms that for him scientific revolutions were irrational, a matter of mob psychology . Kuhn expressly protested against this accusation.

Criticism of the incommensurability and allegations of relativism

While Kuhn's concept of paradigm was taken up many times in the philosophy of science, the incommensurability hypothesis is practically not accepted and is still heavily criticized today. For example, it was objected (for example by John WN Watkins ) that if paradigms or theories were incommensurable - i.e. incomparable - they could not be in a competitive situation with one another. The question of the suppression of one theory by the other would then not arise at all, which contradicts Kuhn's original claim that the new theory and the repressed theory are not compatible. Another objection is that Kuhn could only carry out the research into the history of science, which led him to his views, by considering and comparing the various scientific theories himself from a superordinate position, which should have been impossible according to his incommensurability hypothesis.

According to Kuhn, however, incommensurability should not be understood as a total lack of communication. The entire world view does not change, because the following theories must at least be recognizable as such in order to be called incommensurable at all. So there is a common core of incommensurable theories that enables a comparison.

Thomas Kuhn was personally convinced that progress in science could not be overlooked. However, he did not see progress as a goal-oriented process towards a final, objective description of reality, but as a process similar to Darwin's evolution , in which old theories are replaced by better new ones, but which is not goal-oriented.

In an essay, the American physicist and Nobel Prize winner Steven Weinberg criticized Kuhn's position as “radical skepticism ”, which leads to the relativistic view that science, like “democracy or baseball”, is merely a social construction. If incommensurable scientific theories could only be judged within their paradigm, they would not occupy a privileged position over other, non-scientific theories. Weinberg considers this view to be unacceptable and tries to refute Kuhn's theses of the incommensurability of scientific revolutions in his essay.

The criticism that Kuhn, if there are no objective criteria for the choice of theories, portrays the history of science as an irrational process that is only the result of power and discipline, and that Kuhn's position ultimately leads to total method and theory relativism, aims in a similar direction , on " anything goes " by Paul Feyerabend .

Kuhn defended himself against these accusations in the decades after writing Structure and took the view that his view of the history of science in no way led to relativism.

Popular use of Kuhn's philosophy

The fame of Thomas Kuhn's theses and his sometimes quasi- poetic language has led to many misinterpretations in the history of reception . In particular, the concept of the paradigm shift later became a colorful catchphrase that was also adopted outside of scientific theories, as it was used to combine modern values ​​such as innovation, progress, creativity and the like. a. linked. For example, Samuel P. Huntington uses the paradigm shift thesis in his book Clash of Cultures to explain the rise of his civilization paradigm .

The popularization to the general concept and the "development towards arbitrariness" as well as the "cult status" of the term have made Kuhn appear again and again as a pioneer of postmodernism , although he has explicitly distanced himself from it.

Kuhn himself saw the transfer of his findings from the history of the natural sciences to other areas of knowledge, such as sociology , as problematic.


In honor of Thomas Kuhn, the International Academy of Science together with Yuan T. Lee presented the Thomas Kuhn Award .


  • The Copernican Revolution: Planetary Astronomy in the Development of Western Thought. Harvard University Press, Cambridge 1957.
  • The Structure of Scientific Revolutions (= International Encyclopedia of Unified Science . Volume 2, No. 2.) University of Chicago Press, Chicago 1962; 6th edition 1966.
    • German: The structure of scientific revolutions. Suhrkamp, ​​Frankfurt am Main 1967; 2nd edition in 1976.
  • The Essential Tension: Selected Studies in Scientific Tradition and Change. University of Chicago Press, Chicago 1977, ISBN 0-226-45806-7 .
    • German: The emergence of the new: Studies on the structure of the history of science. Suhrkamp, ​​Frankfurt am Main 1978, ISBN 3-518-07836-4 .
  • Black-Body Theory and the Quantum Discontinuity 1894-1912. Clarendon, Oxford 1978, ISBN 0-19-502383-8 .
  • The Road Since Structure: Philosophical Essays 1970-1993. With an autobiographical interview. University of Chicago Press, Chicago 2000, ISBN 0-226-45798-2 .


  • Daniela Bailer-Jones, Cord Friebe: Thomas Kuhn. Mentis, Paderborn 2009.
  • Alexander Bird: Thomas Kuhn. Acumen, Chesham 2000.
  • William J. Devlin, Alisa Bokulich (eds.) (2015): Kuhn's Structure of Scientific Revolutions - 50 Years On . Berlin: Springer 2015.
  • Steve Fuller : Thomas Kuhn: A Philosophical History for Our Times. University of Chicago Press, Chicago 2000.
  • Wolfgang Deppert , B. Lohff, J. Schaefer: The Interdependence of Paradigm and Normal Science: Three Examples in the Field of Cardiovascular Science. In: J. Mol. And Cell. Cardiology, 23: 395-402 (1991).
  • Steve Fuller: Kuhn vs. Popper: the struggle for the soul of science. Icon, Duxford 2003 (study on the epistemological dispute between Popper and Kuhn).
  • Paul Hoyningen-Huene : The philosophy of science Thomas S. Kuhns. Reconstruction and basic problems . Vieweg, Braunschweig 1989 ( Reconstructing Scientific Revolutions: Thomas Kuhn's Philosophy of Science . University of Chicago Press, 1993). (Download, Book No. 3)
  • Paul Hoyningen-Huene: Thomas S. Kuhn: The Structure of Scientific Revolutions (The Structure of Scientific Revolutions, 1962). In: interpretations. Major works of philosophy: 20th century. Reclam, Stuttgart 1992, pp. 314-334.
  • Paul Hoyningen-Huene: Thomas S. Kuhn. In: Journal for General Philosophy of Science. Volume 28, 1997, pp. 235-256. ( online ; PDF; 2.2 MB). Retrieved March 2, 2013
  • James A. Marcum: Thomas Kuhn's revolution: an historical philosophy of science. Continuum, London 2005.
  • Thomas Nickles (Ed.): Thomas Kuhn (Contemporary Philosophy in Focus). Cambridge University Press, Cambridge 2003.
  • John Preston: Kuhn's "The Structure of Scientific Revolutions": A Reader's Guide . London: Continuum 2008.
  • Uwe Rose: Thomas S. Kuhn: Understanding and misunderstanding. The history of its reception. (PDF; 2.8 MB). Dissertation . University of Göttingen, 2004.
  • David C. Stove: Scientific Irrationalism: Origins of a Postmodern Cult. Transaction Publishers, New Brunswick 2001.
  • K. Brad Wray: Kuhn's Evolutionary Social Epistemology. Cambridge University Press, Cambridge 2011.

Web links


  1. ^ Paul Hoyningen-Huene: Thomas S. Kuhn 1997, p. 1f. (pdf)
  2. Ludwik Fleck: Origin and Development of a Scientific Fact. Introduction to the teaching of thinking style and thinking collective. [Basel 1935] Frankfurt am Main 1980.
  3. ^ Kuhn: The structure of scientific revolutions. 1967, p. 9, foreword.
  4. ^ Member History: Thomas S. Kuhn. American Philosophical Society, accessed January 4, 2019 .
  5. ^ Deceased Fellows. British Academy, accessed June 22, 2020 .
  6. ^ A b c Kuhn, Thomas S. In: Science in the Contemporary World: An Encyclopedia. ABC-CLIO, Santa Barbara 2005. Credo Reference. Retrieved May 25, 2011.
  7. ^ Paul Hoyningen-Huene: Kuhn's Development Before and After Structure. In: Kuhn's Structure of Scientific Revolutions - 50 Years On , ed. by WJ Devlin and A. Bokulich: Springer 2015, pp. 185–195, here p. 191.
  8. ^ Kuhn: The Essential Tension. 1959.
  9. ^ Kuhn: The structure of scientific revolutions. 1967, p. 142.
  10. Thomas S. Kuhn: The structure of scientific revolutions. With a postscript from 1969. 5th edition. Suhrkamp, ​​Frankfurt am Main 1981, ISBN 3-518-07625-6 , p. 186.
  11. In an interview in 1995/97 Kuhn formulated: " Paradigm was a perfectly good word, until I messed it up." (" Paradigm was a thoroughly good word until I messed it up .") Kuhn: The road since structure. 2000, p. 298; see. also the following statements with reference u. a. on M. Masterman, (online) . - For the original meaning of the concept of paradigm and its current general use see P. Hoyningen-Huene: Paradigma. In: Christian Bermes, Ulrich Dierse (Hrsg.): Key terms of the philosophy of the 20th century. (= Archive for the history of concepts. Special issue 6). Meiner, Hamburg 2010, ISBN 978-3-7873-1916-9 , pp. 279-289.
  12. ^ Kuhn: The structure of scientific revolutions. Pp. 30 and 35
  13. ^ Rose: Thomas S. Kuhn. 2004, p. 152.
  14. ^ Kuhn: The structure of scientific revolutions. 1967, p. 149. → This declaration reads as follows in a later edition:
    [A paradigm works] by telling the scientist what entities are in nature and what are not, and how they behave. This information creates a map, the details of which are elucidated by mature scientific research. And since nature is far too complex and diverse to be explored with good luck, this map is just as important for the continuous development of science as observation and experiment. Kuhn: The structure ... p. 121.
  15. ^ Kuhn: The structure of scientific revolutions. P. 126.
  16. ^ Kuhn: The structure of scientific revolutions. 1967, p. 199.
  17. ^ Paul Hoyningen-Huene : Three Biographies: Kuhn, Feyerabend, and Incommensurability. In: Randy Harris (Ed.): Rhetoric and Incommensurability. Parlor Press, West Lafayette 2005, pp. 150-175.
  18. ^ Kuhn: The structure of scientific revolutions. P. 159 ff.
  19. See e.g. BP Hoyningen-Huene: Irrationality in Scientific Development? In: U. Arnswald, H.-P. Schütt: Rationality and Irrationality in Science. VS Verlag für Sozialwissenschaften, Wiesbaden 2011, pp. 38–53.
  20. Imre Lakatos, Alan Musgrave (Ed.): Criticism and the Growth of Knowledge. Cambridge 1970, p. 178.
  21. ^ John WN Watkins: Against "Normal Science". In: Imre Lakatos, Alan Musgrave (Eds.): Criticism and the Growth of Knowledge. Cambridge 1970, pp. 25-38.
  22. Stephen Weinberg: The revolution that didn't happen. In: The New York Review of Books. October 8, 1998, pp. 48-52.
  23. ^ Rose: Thomas S. Kuhn. 2004, p. 33.