Thomas S. Kuhn
Science does not progress in a smooth, linear fashion but instead evolves through sudden, radical overhauls called paradigm shifts.
Normal science focuses on refining established theories rather than discovering new conceptual phenomena.
Anomalies that consistently resist explanation cause a crisis that forces researchers to question their fundamental assumptions.
A scientific revolution occurs when a new paradigm replaces an older one, drastically shifting the acceptable methods and standards of the discipline.