Gregory House repeatedly uses the phrase “Everybody lies” in House, M.D. It expresses his belief that patients, relatives, and colleagues routinely conceal information, whether deliberately or because they misunderstand their own behavior.
The line functions as both a slogan and a diagnostic principle. House often challenges a patient’s account, searches for omitted details, and treats inconsistencies as clues. The phrase also reflects his broader distrust of social conventions and his preference for observable evidence over comforting explanations.
“Everybody lies” is associated with the series, but House does not use it as a literal claim that every person lies constantly. Instead, it dramatizes the show’s recurring idea that medical diagnosis depends on questioning testimony and testing assumptions. The phrase became one of the character’s best-known catchphrases.