What I got out of this was that two gentlemen were talking about prisoners in a cave only being able to see what shadows. Behind them there is a wall with some type of a window and behind that was a fire. People would walk in front of the fire and since the prisoners could not turn their heads, the only saw shadows. The two men talk about one of the prisoners being allowed to leave. Once he leaves, he turns his head to look at the light. Upon his first gaze, it hurts his eyes. Eventually he leaves and everything he sees hurts