Semmelweis Reflex
Semmelweis Effect
A metaphor for the reflex-like tendency to reject new evidence or new knowledge because it contradicts established norms, beliefs or paradigms.
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Origin
Named after Ignaz Semmelweis (1818–1865), who in 1847 at Vienna General Hospital discovered that disinfecting hands with chlorine solution dramatically reduced maternal mortality from childbed fever — from around 18% to under 2%. His colleagues rejected the findings, and Semmelweis died in an asylum before germ theory vindicated him. The term was popularized by Robert Anton Wilson in the 1979 book The Game of Life.
Updated February 22, 2026