The story
Traditional sentiment, both in literal and metaphorical sense, dating to ancient works such as Aristophanes' The Frogs, and appearing in various forms in various Islamic and European medieval texts.
Etymology from Wiktionary, CC BY-SA 4.0.
bad money drives out good
Today it means: Debased coinage (with low levels of precious metals) replaces purer coinage (with higher levels of precious metals). Full definition →