14/12/2025
According to the work of physicist and philosopher of science Thomas Kuhn, scientific knowledge tends to develop in discontinuous stages, rather than steadily accumulating.
In Normal science a paradigm emerges: a shared set of theories, methods, assumptions, and standards. Scientists focus on “puzzle-solving” within this framework, not questioning fundamentals.
Most day-to-day science happens here.
Anomalies in the current paradigm. Persistent observations appear that don’t fit the paradigm. At first, they’re ignored, explained away, or treated as experimental error. Over time, anomalies accumulate.
Crisis starts to occur. Anomalies become too serious to dismiss. Confidence in the existing paradigm weakens. Alternative ideas begin to be taken seriously.
Scientific revolution. A new paradigm emerges that explains the anomalies better. This is not a smooth update but a conceptual break. Old and new paradigms are often incommensurable (they don’t share the same assumptions or even meanings of key terms).
Paradigm shift → New normal science. The new paradigm becomes dominant. Textbooks are rewritten. Normal science resumes under the new framework. The cycle can begin again.
We are in a Kuhn cycle now in biology, evolutionary biology and the old 19th century germ theory. It’s not going to be an easy change and as Kuhn said not all will accept the change, a lot will be intransigent, and incredulous as we have seen over certainly the last few years, even decades.
If you are interested is this topic might I suggest Thomas Kuhn’s book from 1962, The Structure of Scientific Revolutions.