In vino veritas

In vino veritas is a Latin phrase that means "in wine, truth", suggesting a person under the influence of alcohol is more likely to speak their hidden thoughts and desires. The phrase is sometimes continued as, "In vino veritas, in aqua sanitas", i.e., "In wine there is truth, in water there is health." Similar phrases exist across cultures and languages.

The expression, together with its counterpart in Greek, "Ἐν οἴνῳ ἀλήθεια" (En oinōi alētheia), is found in Erasmus' Adagia, I.vii.17.Pliny the Elder's Naturalis historia contains an early allusion to the phrase. The Greek expression is traced back to a poem by Alcaeus.

Herodotus asserts that if the Persians decided something while drunk, they made a rule to reconsider it when sober. Authors after Herodotus have added that if the Persians made a decision while sober, they made a rule to reconsider it when they were drunk (Histories, book 1, section 133). The Roman historian Tacitus described how the Germanic peoples kept council at feasts, where they believed that drunkenness prevented the participants from dissembling.

In Western European countries the expression has been incorporated in local language versions. In Dutch, "De wijn in het lijf, het hart in de mond. Een dronken mond spreekt 's harten grond" ("Wine in the body, heart in the mouth. A drunken mouth speaks the heart's meaning"). In German, "Trunkner Mund verrät des Herzens Grund" ("A drunken mouth betrays the heart's meaning") and "Trunkener Mund tut Wahrheit kund" ("A drunken mouth does a favor to the truth"). In English, "What soberness conceals, drunkenness reveals." and "He speaks in his drink what he thought in his drouth". In French, "Ce que le sobre tient au cœur est sur la langue du buveur." ("What the sober hold in their heart is on the drinker's tongue"). In Spanish, "Despues de beber cada uno dice su parecer" ("After drinking everyone speaks their opinion") and "Cuando el vino entra el secreto se sale afuera" ("When the wine enters, the secret comes out").

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