what relation does it have to plato?
The scholar of humanities Frederick A. de Armas notes parallels between Plato's and Tolkien's rings.
One Ring
The scholar of humanities Frederick A. de Armas notes parallels between Plato's and Tolkien's rings, and suggests that both Bilbo and Gyges, going into deep dark places to find hidden treasure, may have "undergone a Catabasis", a psychological journey to the Underworld.

lord of the rings what does the ring represent Ring of Power what is its purpose? It was forged by the Dark Lord Sauron during the Second Age to gain dominion over the free peoples of Middle-earth. where is this place located? It is the fictional setting, describing the human-inhabited world, that is, the central continent of the Earth. what are the names of the people from the place you just mentioned? Elves, Men, Dwarves, Hobbits, Ents, Orcs and Trolls, as well as various spirits, the Valar and Maiar. is the ring real? No, it is a central plot element in J. R. R. Tolkien's "The Lord of the Rings". who created it? Dark Lord Sauron when? During the Second Age how does it look? It was made simply of gold, it could change size, and perhaps its weight. does it have any special powers? Yes, its primary power was control of the other Rings of Power and domination of the wills of their users. what are people who carry the ring called? Ring-bearers what are their names? Bilbo, Frodo, and Sam what happens to them when they put it on? It offers power to its wearer, and progressively corrupts the wearer's mind to evil; the effect is strongly addictive. is the ring addictive? The power of the ring is addictive. what relation does it have to nibelung? Parallels have been drawn between the literary device of Tolkien's Ring and the titular ring in Richard Wagner's "Der Ring des Nibelungen". does the ring have any hidden meaning? UNANSWERABLE has it been adapted into anything? A tabletop roleplaying game set in Middle-earth and called "The One Ring" was manufactured by Cubicle 7; a new edition is planned by a partnership of Sophisticated Games and Free League Publishing from 2020.
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One Ring [SEP] Parallels with Plato's "Republic"
In Katz's view, Tolkien's story "demonstrate[s] various responses to the question posed by Plato: would a just person be corrupted by the possibility of almost unlimited power?" The question is answered in different ways: Gollum is weak, quickly corrupted, and finally destroyed; Boromir begins virtuous but like Plato's Gyges is corrupted "by the temptation of power" from the Ring, even if he wants to use it for good, but redeems himself by defending the hobbits to his own death; the "strong and virtuous" Galadriel, who sees clearly what she would become if she accepted the ring, and rejects it; the immortal Tom Bombadil, exempt from the Ring's corrupting power and from its gift of invisibility; Sam who in a moment of need faithfully uses the ring, but is not seduced by its vision of "Samwise the Strong, Hero of the Age"; and finally Frodo who is gradually corrupted, but is saved by his earlier mercy to Gollum, and Gollum's desperation for the Ring.