In Plato’s Republic, and his Phaedo, the Myth of Er is recounted to explain the immortality of the soul and the importance of keeping one’s soul morally pure. Myth in this story doesn’t mean the fable or legend of Er but the word or account of Er.

In the Myth of Er a soldier killed in battle is taken to the afterlife where souls are judged for their actions on Earth. Er, though, rather than be judged, is allowed to witness the fate of new souls’ arrival and report his sights and experiences back to the people of Earth.

The judges send the good souls upward through the celestial spheres, which Plato modeled as the Spindle of Necessity; to further cleanse their souls so they can be sent back to Earth to inhabit a new body, forgetful of their past life. The bad souls descend into the ground and return dirty and tired where they are required to pay a penalty before returning to a new life on Earth. The truly evil are forever confined to the underground to be tormented until the end of time.  

In the Myth of Er the three Fates are responsible for weaving the threads of man’s destiny, maintaining the cycle of birth, experience, and death symbolized by the Spindle of Necessity.

Source: Greek Mythology.com. Plato’s Phaedo. Plato’s Republic Book 10. Epoch Times. Graphic: The Three Fates, painting by Paul Thumann, c. 1800s. Public Domain.