The concept of a ‘paradigm shift’ was first outlined by philosopher of science Thomas Kuhn in his influential work The Structure of Scientific Revolutions. Kuhn argues that science usually progresses slowly but steadily by adding to the stock of existing knowledge through extending theory, performing more experiments, and collecting more observations. This ‘normal science’ operates under what Kuhn called ‘paradigms’, which are particular sets of assumptions, approaches, norms, and theoretical frameworks, in which research in a particular field is conducted. The neo-Darwinian synthesis of natural selection with genetics is an example of a contemporary paradigm, while Ptolemaic geocentric astronomy is an example of a paradigm that has now been surpassed.
The revolutionary process wherein one paradigm is increasingly challenged and rejected in favour of a new paradigm Kuhn termed a ‘paradigm shift’. Paradigm shifts typically occur, Kuhn argues, when an existing paradigm faces a sufficiently large number of insoluble problems, such as theoretical difficulties or conflicting observations that cannot be reconciled. These typically build up over time until a ‘crisis point’ is reached, when the time becomes ripe for a paradigm shift. A historical example would be the progressive difficulties encountered within the paradigm of classical physics in the late 19th and early 20th centuries, which eventually led to the paradigm shifts associated with the rise of relativity theory and quantum mechanics. Kuhn’s notion of paradigm shifts has been subject to considerable criticism and has sparked much debate. Even for those who disagree with his analysis of the scientific method, paradigm shifts are still a crucial concept to understand in philosophy of science.
Paradigm shift: a short introduction to the key idea
An introduction to Thomas Kuhn’s The Structure of Scientific Revolutions: a brief video introduction
The use and abuse of Kuhn’s ‘paradigm shift’: a helpful caution against the careless overuse of this term
Thomas Kuhn’s theory of scientific revolutions: a short introduction from a set of philosophy lecture notes
Scientific revolutions: a detailed discussion of Kuhn’s philosophy of science from the Stanford Encyclopedia of Philosophy