Lethe

In Greek mythology, Lethe /ˈliːθi/ (Greek: Λήθη, Lḗthē; Ancient Greek: [lɛ́:tʰɛː], Modern Greek: [ˈliθi]) was one of the five rivers of the underworld of Hades. Also known as the Ameles potamos (river of unmindfulness), the Lethe flowed around the cave of Hypnos and through the Underworld, where all those who drank from it experienced complete forgetfulness. Lethe was also the name of the Greek spirit of forgetfulness and oblivion, with whom the river was often identified.

In Classical Greek, the word literally means "oblivion", "forgetfulness", or "concealment". It is related to the Greek word for "truth", aletheia (), which through the privative alpha literally means "un-forgetfulness" or "un-concealment".

Lethe, the river of forgetfulness, was one of the five rivers of the Greek underworld, the other four being Styx, Acheron (the river of sorrow), Cocytus (the river of lamentation) and Phlegethon (the river of fire). According to Statius, it bordered Elysium, the final resting place of the virtuous. Ovid wrote that the river flowed through the cave of Hypnos, god of sleep, where its murmuring would induce drowsiness.

The shades of the dead were required to drink the waters of the Lethe in order to forget their earthly life. In the Aeneid, Virgil writes that it is only when the dead have had their memories erased by the Lethe that they may be reincarnated.

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