Currency is based on agreement, but gold and silver are inherently valuable. This is ingrained in human consciousness. Robert Kiyosaki called gold and silver "God's money." Mike Maloney always makes sure to differentiate between currency and money (dollars versus gold and silver). Civilizations may use whatever currency their governments create because it's what the legal system requires, but the universe has a law beyond the paper world that was created by man to take power over other men. In the paper world, man creates counterfeit "money" to cheat his brother. In the real world, gold and silver have always been money, and this is built into the constitution of the universe.