The Ring of Gyges

In Book 2 of Plato's Republic, the young Glaucon challenges Socrates with a story. A shepherd named Gyges, who works for the king of Lydia, sees the ground split open after an earthquake and finds inside a hollow bronze horse a corpse wearing a gold ring. He discovers that when he turns the ring's setting toward his palm he becomes invisible. He uses this power to seduce the queen, kill the king with her help and seize the throne. Glaucon then asks Socrates to imagine two such rings, one worn by a just man and one by an unjust man. He says no one would have the iron will to stay honest with the power to steal, kill and break any law unseen. People are just only out of fear of punishment or loss of reputation, not because justice is good in itself.¹

Plato wrote the Republic around 375 BCE in Athens, in the years after Socrates' execution and while he was running his Academy. The challenge forces Socrates to defend justice without relying on its rewards, so the rest of the book answers it. His reply is that justice is a kind of health of the soul, in which reason rules the appetites and spirit, and that the unjust person is internally divided and unhappy even if rich and powerful. Plato probably took the Gyges story from a different tale in Herodotus' Histories, where Gyges also takes the Lydian throne, though without any ring.¹²⁴

The ring has become the standard test of moral character. Philosophers use it to ask whether morality depends on being observed, and psychologists and ethicists use the same question when studying anonymity, accountability and cheating. Stories of invisibility rings and cloaks, from folklore to modern fantasy, retell it, though whether any particular author was influenced by Plato is often debated.⁴