Montesquieu

When the orga­ni­zed poli­ties are mas­ters of the world, gold and sil­ver increase by the day, either because it is obtai­ned domes­ti­cally, or because it is fet­ched whe­re­ver it is. It decrea­ses, on the contrary, when bar­ba­ric nations pre­vail. We know how scarce these metals were when the Goths and Vandals on the one hand, and the Saracens and Tartars on the other, had inva­ded every land.