BBB Etymology - Grain of salt

From the Latin phrase "cum grano salis." Etymologist Christine Ammer traces it to Pompey's discovery, recorded by Pliny in 77 A.D., of an antidote to poison which had to be taken with a small amount of salt to be effective. Everyone else seems to bypass that explanation and trace "with a grain of salt" to the dinner table, where a dash of salt can often make uninspired cooking more palatable. "With a grain of salt" first appeared in English in 1647, and has been in constant use since.
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