Ring of Gyges

The Ring of Gyges is a mythical magical artifact mentioned by the philosopher Plato in Book 2 of his Republic (2:359a–2:360d). It granted its owner the power to become invisible at will. Through the story of the ring, Republic considers whether an intelligent person would be moral if he did not have to fear being caught and punished for doing injustices.

Gyges of Lydia was a historical king, the founder of the Mermnad dynasty of Lydian kings. Various ancient works—the most well-known being The Histories of Herodotus—gave different accounts of the circumstances of his rise to power. All, however, agree in asserting that he was originally a subordinate of King Candaules of Lydia, that he killed Candaules and seized the throne, and that he had either seduced Candaules' Queen before killing him, married her afterwards, or both.

In Glaucon's recounting of the myth (which is clearly not based on historical fact), an unnamed ancestor of Gyges was a shepherd in the service of the ruler of Lydia. After an earthquake, a cave was revealed in a mountainside where he was feeding his flock. Entering the cave, he discovered that it was in fact a tomb with a bronze horse containing a corpse, larger than that of a man, who wore a golden ring, which he pocketed. He discovered that the ring gave him the power to become invisible by adjusting it. He then arranged to be chosen as one of the messengers who reported to the king as to the status of the flocks. Arriving at the palace, he used his new power of invisibility to seduce the queen, and with her help he murdered the king, and became king of Lydia himself.

In Republic, the tale of the ring of Gyges is described by the character of Glaucon who is the brother of Plato. Glaucon asks whether any man can be so virtuous that he could resist the temptation of being able to perform any act without being known or discovered. Glaucon suggests that morality is only a social construction, the source of which is the desire to maintain one's reputation for virtue and justice. Hence, if that sanction were removed, one's moral character would evaporate.

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