Plato’s Allegory of the Cave - Alex Gendler

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Twenty four hundred years ago, Plato, one of history’s most famous thinkers, said life is like being chained up in a cave forced to watch shadows flitting across a stone wall. Beyond sounding quite morbid, what exactly did he mean? Alex Gendler unravels Plato's Allegory of the Cave, found in Book VII of "The Republic."

Lesson by Alex Gendler, animation by Stretch Films, Inc.

What is reality, knowledge,
the meaning of life?

Big topics you might tackle figuratively

explaining existence as a journey
down a road or across an ocean,

a climb, a war, a book, a thread, a game,
a window of opportunity,

or an all-too-short-lived
flicker of flame.

2,400 years ago,

one of history's famous thinkers said
life is like being chained up in a cave,

forced to watch shadows
flitting across a stone wall.

Pretty cheery, right?

That's actually what Plato suggested
in his Allegory of the Cave,

found in Book VII of "The Republic,"

in which the Greek philosopher
envisioned the ideal society

by examining concepts
like justice, truth and beauty.

In the allegory, a group of prisoners
have been confined in a cavern since birth,

with no knowledge of the outside world.

They are chained, facing a wall,
unable to turn their heads,

while a fire behind them
gives off a faint light.

Occasionally, people pass by the fire,

carrying figures of animals and other objects
that cast shadows on the wall.

The prisoners name
and classify these illusions,

believing they're perceiving
actual entities.

Suddenly, one prisoner is freed
and brought outside for the first time.

The sunlight hurts his eyes and he finds
the new environment disorienting.

When told that the things
around him are real,`

while the shadows were mere reflections,
he cannot believe it.

The shadows appeared much clearer to him.

But gradually, his eyes adjust

until he can look
at reflections in the water,

at objects directly,

and finally at the Sun,

whose light is the ultimate source
of everything he has seen.

The prisoner returns to the cave
to share his discovery,

but he is no longer used to the darkness,

and has a hard time
seeing the shadows on the wall.

The other prisoners think the journey
has made him stupid and blind,

and violently resist
any attempts to free them.

Plato introduces this passage
as an analogy

of what it's like to be a philosopher
trying to educate the public.

Most people are not just comfortable
in their ignorance

but hostile to anyone who points it out.

In fact, the real life Socrates
was sentenced to death

by the Athenian government
for disrupting the social order,

and his student Plato
spends much of "The Republic"

disparaging Athenian democracy,

while promoting rule by philosopher kings.

With the cave parable,

Plato may be arguing that the masses
are too stubborn and ignorant

to govern themselves.

But the allegory has captured
imaginations for 2,400 years

because it can be read in far more ways.

Importantly, the allegory is connected
to the theory of forms,

developed in Plato's other dialogues,

which holds that
like the shadows on the wall,

things in the physical world are flawed
reflections of ideal forms,

such as roundness, or beauty.

In this way, the cave leads to many
fundamental questions,

including the origin of knowledge,

the problem of representation,

and the nature of reality itself.

For theologians, the ideal forms
exist in the mind of a creator.

For philosophers of language
viewing the forms as linguistic concepts,

the theory illustrates the problem
of grouping concrete things

under abstract terms.

And others still wonder whether
we can really know

that the things outside the cave
are any more real than the shadows.

As we go about our lives,

can we be confident
in what we think we know?

Perhaps one day,

a glimmer of light may punch a hole
in your most basic assumptions.

Will you break free to struggle
towards the light,

even if it costs you
your friends and family,

or stick with comfortable
and familiar illusions?

Truth or habit? Light or shadow?

Hard choices, but if it's any consolation,
you're not alone.

There are lots of us down here.