The myth speaks of how to keep guardians, especially those of the city, uncorrupt. It is suggested that they are not to have any material things of value and that they are never to even drink from gold or silver. When done reading this tale, I immediately thought that in order for a man to gain mettle, he must first give up all other metals (in other words money). Since, money was made out of metal. So, the basic outline of this myth is that in order to create uncorrupted men to guard the city they must live without materialistic goods/money. If this idea on how to create uncorrupted guardians were extended to cover the entire population then we would have the beginnings of communist like society. A society without rank and with everyone depending upon each other.

myth of metals

Plato's Republic Reflections