The Good, the Line and the Cave

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The Good, the Line and the Cave
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The Philosopher rulers must know the Good

• The good is a motivator. Everyone pursues what
  they believe to be good.
• The philosopher kings will know what the good is.
  They will therefore pursue what really is good.

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• A doctor can know medicine, and yet still use
  that knowledge to poison people
• A Pilot can know the art of navigation, and use
  it to run the ship aground.
• Likewise, the mere knowledge of justice is not by
  itself going to motivate someone to be or produce
  justice.

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• You have to know not just what justice is, you
  need to know that justice is good.
• Knowledge of the good is distinctive because it
  motivates behavior.
• If I know justice is good, then I will want to
  produce just things (cities) and be a just person.

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But what is the form of the Good?

• The Good is to the intelligible world what the
  sun is to the visible world
• The sun causes visible things to come into
  existence (grow), and it also provides light so
  we can see them
• The good allows us to see , understand, the
  forms
• The good is also the cause of the existence of
  the forms

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• Because the form of justice derives from the
  Good, we know that justice is good.
• All the forms are derived from the good
• And since the forms cause the structure of the
  sensible world, the Good is the cause of
  everything.

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What about evil?

• If everything derives from the Good, then it
  seems everything should be GOOD
• But everything is not good.
• How can Plato account for the existence of
  bad/evil, given that everything derives from The
  Good.

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One possibility Evil is a privation

• Injustice may not be real property at all
• Just as being blind is the lack of sight, so
  being bad may be the lack of good.
• there is no form of injustice, but there are
  various ways in which a person or city can
  deviate from the form of justice, become less
  like the form.

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The Line

• The line illustrates the relationship between the
  intelligible and sensible worlds.
• In the sensible world, the are both things and
  images (objects of belief and objects of
  imagination
• The objects of imagination are images of the
  objects of belief (things)

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The sensible world is an image

• Likewise the sensible world, ordinary physical
  things, are images, imperfect copies of the ideal
  forms.

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The Cave!

• The cave also illustrates the sensible and
  intelligible world.
• We are all cave dwellers, who take the images of
  things to be reality

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Questions about the cave

• The cave dwellers treat shadows as reality
• Shadows correspond to imagination
• How does this correspond to ordinary life? In
  what way do we confuse imagination with physical
  reality (which itself is not really real)

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• We confuse image with reality when we take
  physical things to be what we perceive them to
  be, when we fail to distinguish our perspective
  on a thing, and the thing itself
• We confuse imagination for reality when we allow
  conventional wisdom, the media,
• To interpret reality for us.

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Why do the philosophers go back to the cave

• The cave, the city, needs rulers. The
  philosophers dont want to be in the cave (its
  more fun outside)
• But they go back because the ought to .
• This the one place in the Republic where someone
  clearly acts against their own self interest.

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The cave illustrates why philosophers make the
best rulers

• Because the philosophers dont want to rule, they
  will not compete to rule. Because they know the
  cave is just a cave, they will not be corrupted
  by the temptations of cave life (wealth etc)
• The philosophers have seen reality, they know the
  forms. So they are able to make the models in the
  cave more like the reality they imitate.