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The cave
SOCRATES: Imagine this: People live under the earth in a cavelike dwelling. Stretching a long way
up toward the daylight is its entrance, toward which the entire cave is gathered. The people have been in
this dwelling since childhood, shackled by the legs and neck..Thus they stay in the same place so that there
is only one thing for them to look that: whatever they encounter in front of their faces. But because they are
shackled, they are unable to turn their heads around.
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SOCRATES: And if someone even forced him to look into the glare of the fire, would his eyes nothurt him, and would he not then turn away and flee [back] to that which he is capable of looking at? And would he not decide that [what he could see before without any help] was in fact clearer than what was nowbeing shown to him?
GLAUCON: Precisely.
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SOCRATES: And now, I responded, consider this: If this person who had gotten out of the cave were to go back down again and sit in the same place as before, would he not find in that case, coming suddenly out of the sunlight, that his eyes ere filled with darkness?"
GLAUCON: Yes, very much so.
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SOCRATES: Now if once again, along with those who had remained shackled there, the freed person had to engage in the business of asserting and maintaining opinions about the shadows -- while his eyes are still weak and before they have readjusted, an adjustment that would require quite a bit of time -- would he not then be exposed to ridicule down there? And would they not let him know that he had gone up but only in order to come back down into the cave with his eyes ruined -- and thus it certainly does not pay to go up.
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SOCRATES: And if they can get hold of this person who takes it in hand to free them from their chains and to lead them up, and if they could kill him, will they not actually kill him?
GLAUCON: They certainly will.