Falsification

Falsification is a methodological principle in the philosophy of science describing the process of attempting to refute a claim or theory through observation and experiment. A theory is considered scientific if it is falsifiable, meaning it makes predictions that could, in principle, be shown false by evidence.

Karl Popper popularized falsifiability as a demarcation criterion between science and non-science. He argued that scientific progress comes through bold conjectures tested by critical experiments, and that a single robust refutation can invalidate a theory, whereas mere confirmation is not sufficient.

Application and method: Falsification involves deriving testable predictions from a theory, designing experiments or observations to challenge them, and then revising or discarding the theory if predictions fail. A classic example is the statement all swans are white, which was falsified by the discovery of black swans.

Limitations: Not all meaningful claims are falsifiable; metaphysical, ethical, or historical claims may lie outside strict scientific testing. The failure to falsify a theory does not prove it true; theories are often revised rather than outright discarded, and many tests provide probabilistic rather than definitive verdicts.

Criticism and alternatives: Falsificationism has been challenged by philosophers such as Thomas Kuhn, Imre Lakatos, and Paul Feyerabend, who argued that science proceeds through competing paradigms or research programs. Some modern views emphasize robustness, model comparison, and Bayesian updating rather than simple falsification.