Teach fish how to swim
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Teach fish how to swim is an idiomatic expression derived from the Latin proverb piscem natare doces. The phrase describes the self-sufficiency of those who know better how to do everything than the experts. It corresponds to the expression, "teaching grandmother to suck eggs".[1] Erasmus attributed the origins of the phrase in his Adagia to Diogenianus.[2]
A corollary idiomatic phrase is part of common usage in Chinese "班門弄斧"[3]
References
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