Imagine a number of people living in an underground cave, which has an entrance that opens towards the daylight. The people have been in this dwelling since childhood, shackled by the legs and neck, such that they cannot move nor turn their heads to look around. There is a fire behind them, and between these prisoners and the fire, there is a low wall. Rather like a shadow puppet play, objects are carried before the fire, from behind the low wall, casting shadows on the wall of the cave for the prisoners to see. Those carrying the objects may be talking, or making noises, or they may be silent. What might the prisoners make of these shadows, of the noises, when they can never turn their heads to see the objects or what is behind them? (c) Plato’s "Republic"