In vino veritas

[Julene]

In vino veritas is a Latin phrase that means in wine there is truth.

The expression, together with its counterpart in Greek, Ἐν οἴνῳ ἀλήθεια (En [oin]ōi alē[theia]), is found in Erasmus Adagia, I.vii.17. [Pliny] [the Elders] Naturalis historia contains an early allusion to the phrase. The Greek expression is traced back to a poem by Alcaeus.
Herodotus asserts, and it is likely enough, that if the [Persians] decided something while drunk, they made a rule to reconsider it when sober. Authors from Herodotus onwards, however, have dared to add 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 always drank while holding councils, as they believed nobody could lie effectively when drunk.
The phrase is often continued as, In vino veritas, in [aqua] sanitas, i.e., In wine there is truth, in water there is health.