There are chained slaves in an underground cave, which has an open end towards the light that reaches all along the cave. Theses people have been here from their childhood, unable to move or to see beyond, being prevented by chains that keep them from turning their heads around. Behind and above them, at a distance, there is fire but between the fire and the people there is a low wall, necessary to foster the illusion for a puppet show. These prisoners in this cave only see their own shadow or the shadows of one another, thrown on the opposite wall of the cave by the fire. To them the truth would literally be nothing but the shadows of the images, and they cannot distinguish the voices of one another from the echoes emanating from the surrounding darkness (Raghavan). .
Given this situation, we might come to the conclusion that if the prisoners were released from their chains they would discontinue to mistake shadows for realities and would be released from their former errors. This is not the case; the allegory states that no such simple deliverance from illusion is possible (Kreis). When any of the prisoners would be freed and urged to stand up and turn his head around and walk toward the light, sharp pains would be experienced. The glare will impair him and he will not be able to see the realities he identified with shadows. If the prisoner is now told that what he is about to see is real and not just a mere shadow he will be confused. He will continue to think that the shadows he saw for that long time in the cave were truer than the real objects that are shown to him. Looking straight into the light will bring pain to his eyes and will make him turn away and take refuge in the objects of vision that have acquired a false but greater reality than the actual things that are being shown to him. If the prisoner is then taken out of the cave into the presence of the sun, his eyes will be blinded and he will not be able to see anything.
