A usually pithy and familiar statement expressing an observation or principle generally accepted as wise or true
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As the famous adage goes "The show must go on," and it did.
Is the adage "The camera never lies" true?
You know the old adage "A picture is worth a thousand words."
This goes to prove the old adage: "You get what you pay for."
There is a common adage in science that the more you study a phenomenon, the more confusing it becomes.