According to philosopher of science Kuhn (1962), research takes place within paradigms. These are scientific findings that are recognized by the scientific community as the foundation for further work and that are summarized in textbooks.
The development of science takes place in a cyclical pattern: Kuhn (1962) made a distinction between ‘‘normal science’’, which is guided by recognized paradigms, and scientific revolutions, which become necessary when deviations can no longer be explained by the existing paradigms. These deviations or anomalies lead to scientific crises, which is when the research community in a research area conducts ‘‘extraordinary science’’. The existing paradigms become blurred, and then the scientific community replaces them with new paradigms (paradigm shift). These scientific revolutions start up a new phase of normal science—without the research in a research area cumulatively approximating closer and closer any absolute truth.