# Gresham's Law

Bad money drives out good. If their face values are almost the
same. Which is usually the case.

This is not limited to money. In general if good one and bad one
have similar face values, there is no reason to make good one. So
bad ones go prevalent.

I guess why the world hegemony has moved from Spain -> Britain ->
US would be also an example. Egypt -> Greece -> Roman empire ->
Germans too. The latter had no culture. So they were cost-effective.