"With a grain of salt" - with reservations; skeptically.  e.g.: ''Take that advice with a grain of salt.'' Literal translation of the LatinLanguage phrase "cum grano salis", first punt into English in 1647. See for instance http://www.word-detective.com/052598.html .

'''Definition''':
* An idiom that means that one should consider the subject discussed with appropriate skepticism
* One should make a RealityCheck with respect to the subject discussed
* Use your own discretion with respect to the subject discussed

The similar-sounding but distinct "pinch of salt", generally used in a cooking context, means ''tweak until optimal''.

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This is the smallest possible unit of untruth.

''(Note: Unsupported. Possibly a TerryPratchett definition.)''
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See: GrainOfTruth, AmericanCulturalAssumption, BritishCulturalAssumption

CategoryIdiom