The invention of paper money in Western economies (borrowed conceptually from Song Dynasty China) introduced a new debasement mechanism: issuing more paper claims on gold or silver than the issuer actually held. The first Western paper monies were issued by the Massachusetts Bay Colony in 1690. Within 30 years, John Law's Banque Royale in France had demonstrated the catastrophic potential at industrial scale. Every paper-money experiment of the 18th century — Continentals, assignats, Bank of England wartime notes — followed the same pattern: issue, over-issue, collapse.