I haven’t come across any other reviews or analyses that have mentioned this connection, but I will be bold and say that Robert A. Heinlein’s Orphans of the Sky is a literary cousin to Plato’s Allegory of the Cave.
Orphans, the first part of which is included in Heinlein’s Future History timeline. Takes the reader aboard a generational spacecraft on course to a distant star system from earth. When the reader comes into the narrative, the journey is well underway, but a mutiny during the ship’s early history has resulted in the killing off of her captain and crew. Over time, the ship’s population, which has seen generations come and go, has forgotten the true purpose of the Trip, as well as the true nature of the ship as a vessel. Now, the Vanguard, as the ship is christened, has become for those who still survive, the totality of the known universe. The Ship does not move. The Ship just Is. It is all that exists for its passengers.
It is in this collective belief that the reader familiar with Plato’s Allegory, as told in his Republic, will draw the parallel. In his Allegory, Plato’s surrogate voice, Socrates, describes a small society of individuals who have lived out their lives in a cave. They are chained to the wall at the back of the cave. They are only able to watch the wall. Behind them, a fire burns, casting shadows of objects passing before it upon the wall. The chained give names to these shadows. This is their reality. This is all they know.
Within the Ship, a class structure has evolved as people have gradually drifted into sub-societal bands based on labor responsibilities. The Scientists hold a high rank within this banded society. But as the Ship has moved further away in time and memory of the mutiny, a new class has arisen in the low-gravity levels of the vessel. This class is known as the muties, both because among them are descendants of the original mutineers and those among them have suffered physiological mutations that have made them outsiders, even enemies, of the rest of the Ship’s passengers.
However, Heinlein gives these outcasts, these lowest of the low, the muties, knowledge of the greatest truth. The muties, chief among them the two-headed Joe-Jim, are like the philosophers who have escaped Plato’s cave. They have seen the stars and know that the Ship is not the whole of existence. When a passenger ventures into the domain of the muties and establishes a tenuous truce, he discovers what is already known to Joe-Jim and attempts, like Prometheus, to bring that knowledge back to the other passengers.
What Heinlein has done with this story is to explore how ready some may be to receive and accept existential knowledge. He also examines how it can be that such knowledge can become lost and forgotten. This novel is tremendously poignant today as, globally, we are experiencing a vast dying out or assimilation of cultures whose heritage and continued existence are crucial to weaving in the whole of humankind’s story.