The story
This proverb dates from c1650, and was popularised by Voltaire [François-Marie Arouet] in the 18th century.
Etymology from Wiktionary, CC BY-SA 4.0.
throw dirt enough, and some will stick
Today it means: If enough allegations are made about someone or something, then even if they are all untrue, people's opinion of the person or thing will be diminished. Full definition →