Plato - Republic

Knowledge & Truth Book V

"Who are the true philosophers?"

“Lovers of the vision of truth" But what does this mean? How do we know truth? 1st step: distinguish sense from

intellect.

Ideas and Things Intellect Beauty is opposite

of ugliness, just of unjust, good of evil, and so on.

Each of these is one thing.

This is not the same as enjoying beautiful things.

Sense Such sense

knowledge is like dreaming.

Beauty, goodness the just seem to change.

The problem: "the beautiful will in some point of view be found ugly."

Ideas and things ~ cont’d Likewise with

other opposites. A large dog is

smaller than a small elephant!

Ideas and Things ~ cont’d

If everything is true ‘in some point of view,’ then those same things are false 'in some point of view.'

That is to say... Nothing is absolutely true. Knowledge is relative.

Plato's answer Things we sense, which can be

beautiful, large, or just 'in a point of view,' are halfway between being and non-being.

Those who know these things without knowing absolute ideas have opinion rather than knowledge.

They are lovers of opinion, not philosophers.

Plato - Republic

Image and Reality Book VI

Absolute ideas and things

What does - say - a lovely rose have to do with absolute beauty?

Socrates begins by distinguishing the visible and the intelligible.

The “Divided Line”

Ascent from images through perceptions through hypotheses to first principles (ideas).

Four Conditions in the soul:• Understanding• Thought (mathematical hypothesis)• Belief or opinion• Imaging (picture-thinking)

Human knowledge moves from pictures, images and analogies to perfect understanding, but how?

The “Divided Line” 1st section - images,

shadows, reflections 2nd section - animals,

things Things in the 1st section

copy those in the 2nd. 3rd section - figures

from the visible realm: mathematics.

4th section - no images but ideas themselves

Visible

Intelligible

Republic – Book VII

The Cave

The Cave

The Cave and the Line

Imagination Belief

Thought

Understanding

The shadows The objects on

the wall Reflections and

shadows Objects outside

the cave

Line Cave

The Interpretation (517b-c)

• The cave itself is a metaphor for knowledge of the sensible world. • The entire realm of sense is only

apparent knowledge.

• The fire – source of light within the Cave – represents the sun. • This corresponds to the lower two

sections of the Line.

The Interpretation (cont’d) The world outside the Cave is the realm

of intelligence. 1st – discursive thought about mathematical

entities. 2nd – understanding of the Forms themselves.

The source of all these is the Good. The Good is “the cause of all that is

correct and beautiful in anything.” (517c)

Application to Education

Education: not putting knowledge into ignorant souls but turning them towards the brightest region of being (518c).

The art of conversion of souls (518d).