Lecture 07 Notes

Plato's Theory of Knowledge

I.    Knowledge in Citizens
II.   The Simile of the Divided Line
III.  The Simile of the Cave
IV.   Brief Summary

I.    Knowledge in Citizens

• The commercial class includes carpenters, merchants, sea captains, and so on.  Notice the following contrasts:

1. Knowing how to build vs. principles of carpentry
2. Knowing how to sell vs. principles of finance
3. Knowing how to sail vs. prniciples of navigation

• Questions: (i) What do carpenters, merchants sailors need to know? (ii) What do those who teach them need to know?

• The military class (the auxiliaries) include the soldiers.  Notice the following contrasts:

1. Knowing how to fight vs. principles of strategy
2. Knowing what to fear vs. principles of psychology

• Questions: (i) What do soldiers need to know? (ii) What do those who teach soldiers need to know?

• The governing class includes the rulers (the guardians).
• Question: What do they need to know?
• Answer: The most abstract principles and objects.
  

II.   The Simile of the Divided Line

 B.   These Spectra Correspond to Plato's Divided Line:

• Segment A represents pictures, shadows, reflections in the water, mirror.
• Segment B represents all material objects of which we’re aware by sensation.
• Segment C represents all ideals of which material objects are likenesses
• Segment D represents mathematical objects which describe ideal structures
• Segments A+B represent the visible realm, accessible to the faculty of sense, of which we have opinion.
• Segments C+D represent the intelligible realm, accessible to the faculty of reason, of which we have knowledge.
• Plato thinks that those who teach must know objects in segments C and D.

III.   The Simile of the Cave

• ...from what is most familiar and vivid, e.g., footballs
• ...to what is less vivid and more abstract: the Forms
• When learn to think abstractly, we think about the Forms.  This will sound foolish and confused to everyone else, just as a football commentator who talked about math will sound foolish and confused.

B.   Those Who Teach Must Know the Forms

• Given (A), we can see why the Cave is an apt simile for this education.

IV.   Brief Summary

A.   Those in the ruling class are society’s teachers

• They frame laws which teach rabble self-discipline.
• They frame laws which teach soldiers courage.
• In order to teach, they must think abstractly about the skills and virtues they impart.
• They must know objects at right end of the Divided Line.
• They must therefore know the Forms.

B.   Their education is allegorized by Simile of the Cave.

C.   The rationale for teaching as they do is partially communicable.