It is a constant because it is always valued by civilizations throughout history as representations of the sun, with silver representing the moon. You are talking about economic rules while I am talking about economic laws. The difference being that laws are historical agreement over many cultures that something has value to society. Rules, however, are fleeting changes at the whims of men over relatively short periods of time. Your own example of the Incas proves this out. BOTH civilizations, which were entirely unconnected, BOTH viewed gold and silver as having value. The theft of the metals by Spain triggered short term market distortions that eventually worked themselves out. Yet, gold is still valuable in Spain today. Is stolen Incan gold still screwing up the Spanish economy now? Only man's interventions in markets distort the value of gold and silver and always temporarily until it returns to its rightful place as valuable. Heck, even JP Morgan summed it up well when he said gold and silver are money. All else is credit. Why? Because gold and silver are the constants and that is law. Credit is man-made and is comprised of rules. Rules are what governs currencies, not laws. If you want to argue with him, go for it.