Plato’s Philosophy

4 Key IdeasVirtue is

Knowledge

The soul is immortal

Knowledge is remembering

The Forms

4 key Influences Socrates

Heraclitus

Pythagoras

Parmenides

Plato’s philosophy begins with a problem of knowledge.

What did Socrates know?

When one knows . . .

• What is it exactly that anyone knows (when they know it)?

• What qualities must any object of knowledge have?

• How can we distinguish true knowing from mere opinion?

• is certain, absolute & objective

• It is one and complete

• Its object is the form of a thing

• grasped by reason

• Is uncertain, relative, subjective

• It is many, diverse, incomplete

• Its object is some thing in a changing world

• grasped by senses

Knowledge Opinion

The Divided Line

A

B

C

D

E

Images, reflections

Sense objects

Objects of math

Forms

imagination

opinion

reasoning

understanding

Complete

Intelligible

Incomplete

Sensible

Eternal &

unchanging

Temporal& spatial

Changing

Plato’s Two-world theory:

Reality & Knowledge are DualThe Forms

Grasped by Reason

Physical World

Experienced through senses

• Question: How is it possible to achieve real knowledge, if our lives are embedded in sense experience?

• Answer: Our souls must have had a prior existence when they were in contact with the forms.

• Soul is the our conduit to knowledge.

All Knowledge is Remembering

• We once existed as pure forms living with the One, the True, the Good and the Beautiful

• We now exist in a world of change and sense and we have forgotten the Truth– distracted by our bodies, by

sensation.

“Know thy self”

The goal of life is to remember the Truth that we have always known and that we

now find reflected in the “form” of things.

Take care of your soul

A living model of the best sort of human life

Our soul’s fate depends on our choices.

EthicsAn explanation of “the good” for human beings

Self & societyAn explanation of how society should be organized & governed

EpistemologyAn explanation of humanknowledge

MetaphysicsAn explanation of reality

An integrated system of philosophy

“Follow the argument.”

No matter where it leads.

The unexamined life is not worth living.

FINI

What is, is what can be thought of

is uncreated

imperishable

entire

immovable

without end

all alike

indivisible

round, like a ball

What is, is. What is not, is not.

• Change & opposition characterize reality

• Underlying coherence of things is the logos