Samuel Goldwyn? George Oppenheimer? Ellenor Stoothoff? Andrew Carnegie? Apocryphal? Dear Quote Investigator: The phrase “like water off a duck’s back” is a well-known idiom that refers to an incident or a comment having little or no effect on a person.[1]Oxford Dictionary of English Idioms, Third Edition, Edited by John Ayto, Oxford Reference Online, Entry: like …