Gresham’s Law / 劣币驱逐良币

Gresham’s Law is the money-use pattern summarized as bad money driving out good when different coins have the same legal face value but different intrinsic or trusted value. 26.牛顿与伪币制造者：可能是斯内普的原型？ makes the mechanism concrete through old clipped silver coins and newer machine-struck coins in late-17th-century England.

If users can pay debts with inferior coins while hoarding, melting, exporting, or selecting away better coins, the public money stock degrades. The source ties this directly to Great Recoinage / 大重铸, Currency Credit, and Counterfeit Currency Policing: good money disappears when everyday users no longer trust that nominal equality reflects real acceptability.

Connections

• Great Recoinage / 大重铸 - source crisis where the law appears.
• Currency Credit - broader trust layer.
• [[RoyalMint|Royal Mint / 皇家造币厂]] - institution trying to restore coin quality.
• [[WilliamChaloner|William Chaloner / 查罗纳]] - counterfeiter exploiting the same trust breakdown.