PHL220: Plato's Allegory of the Cave
Plato's Allegory of the Cave
Epistemology is concerned with 3 primary questions:
- What is knowledge?
- How do we get knowledge?
- What justifies a belief and makes it knowledge?
Some background on Socrates
- ~470 - 399 BC
- Trial recounted by Plato in the Apology. Accused of "not
worshipping the gods whom the State worships and of corrupting
- Events of his execution in Plato's Crito and
Some Background on Plato
- 428-348 BC
- Relatively wealthy student of Socrates
- Was present at the trial of Socrates
- Founded the Academy
- Opposed, as did Socrates, the Sophists.
- Most notable student was Aristotle
- His school, and his dialogues, demonstrate the dialectic.
This dialetical method reveals the sense of Plato that
knowledge is socially found and communicated.
The Allegory of the Cave and it's place in the Republic
- In the Republic, the (character of) Socrates is
trying to answer the question, "what is justice?"
- Socrates concludes that we can discover this by looking
at a just state, and he develops a utopian perfect state
- Socrates argues that only in a just state can virtue
- The allegory of the cave arises in part because Socrates
is trying to explain our discomfort with, and resistance to,
the conclusions of philosophy
Some observations about the allegory
- The cave is itself the condition of the person who does not
love and seek and find wisdom. This ignorant person views changing
shadows and insists dogmatically they are the most real things. He
is angry at the wise for disagreeing with him. He does not believe
- Plato introduced the concept of the Forms (the Ideas, Eidos).
These are unchanging objects that are the most real things; the
world we perceive is a dim shadow of Forms.
- The best examples of Forms are found in mathematics.
- Forms are grasped by reason.
- Plato is thus both a
Rationalist: he believes we primarily acquire knowledge
through reason (as opposed to through the senses).
(Ontological) Idealist: he believes the most real or
the only real things are ideas, the kinds of things grasped by
- In the allegory, the sun is the Form of the Good, and is
the source of all wisdom.
The Forms and Idealism
- Roughly, a Form (eidos) is that which is shared by any
things of one kind (although it is not clear whether Plato
thought every thing had a Form).
- For example, what all triangles share is the Form of
triangularity. Triangularity is the essence of what it is to
be a triangle.
- Plato appears to offer this as a theory of what it is for
things to be of a kind: for any two things to be of kind K
they must share a Form K-ness.
- Aristotle rightly pointed out that this is too strong
with his "third man" argument: if we can only say two things
are share some properties when they share some Form, then how
will we explain that a thing shares it's Form? It would seem
we need yet another Form, ad infinitum.
- Thus, the doctrine of Forms cannot be defined as
explaining all kinds of sharing of properties. But it
could explain some, and it could be a viable form of a theory
of knowledge. Today, it is still popular as a theory of
- Idealism is the view that reality is composed (in some
sense) of ideas.
- Idealism solves one outstanding problem in the theory of
knowledge: if there is a difference between appearance and
reality, how can we ever come to know anything? Here is one
answer: If the grasping of knowledge is the grasping of ideas
(for Plato, of Forms), and if in turn the world is made of
ideas, then there is no gap to be explained or filled in -
knowledge is a kind of direct apprehension of reality.
- Keep both Plato's idealism and rationalism in mind when
we read Berkeley. Berkeley is an idealist who is an
empiricist and who believes the world as perceived is
(largely) the world as it is (his appearance-reality distinction
is much weaker than Plato's).