Hume famously noted the impossibility of the mercantilists' goal of a constant positive balance of trade. As bullion flowed into one country, the supply would increase, and the value of bullion in that state would steadily decline relative to other goods. Conversely, in the state exporting bullion, its value would slowly rise. Eventually, it would no longer be cost-effective to export goods from the high-price country to the low-price country, and the balance of trade would reverse. Mercantilists fundamentally misunderstood this, long arguing that an increase in the money supply simply meant that everyone gets richer.