Imagine prisoners, who have been chained since their childhood deep inside a cave: not only are their limbs immobilized by the chains; their heads are chained in one direction as well, so that their gaze is fixed on a wall.
Behind the prisoners is an enormous fire, and between the fire and the prisoners is a raised walkway, along which statues of various animals, plants, and other things are carried by people. The statues cast shadows on the wall, and the prisoners watch these shadows. When one of the statue-carriers speaks, an echo against the wall causes the prisoners to believe that the words come from the shadows.
拙訳。
囚人たちを想像してみよう。幼い頃から洞窟の奥深くに鎖で繋がれた囚人たちのことを。彼らは体を動かすことはもとより、頭も一方向にしか向けられないように繋がれているので、壁しか見ることができない。囚人たちの背後には巨大なかがり火があって、その間の歩道をさまざまな動物、植物などの彫像が運ばれていく。それらの像は壁に影を投げる。囚人たちはその影を見る。彫像を運ぶ誰かが話せば、その声は壁に谺して、囚人たちはその言葉が影から発せられたと信じるようになるだろう。
