gresham's law, n.All

Copernicus ⁠​‌​​​‌​​​‌​‌‌​​​​‌​‌​​‌‌​‌​​‌​​​​​‌‌​​‌​​​‌‌​‌‌​⁠described how bad money drives out good decades before Gresham got the credit.