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What is reality, knowledge,[br]the meaning of life?

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Big topics you might tackle figuratively

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explainIing existence as a journey [br]down a road or across an ocean,

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a climb, a war, a book, a thread, a game,[br]a window of opportunity,

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or an all-too-short-lived [br]flicker of flame.

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2,400 years ago,

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

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forced to watch shadows [br]flitting across a stone wall.

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Pretty cheery, right?

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

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found in Book VII of "The Republic,"

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in which the Greek philosopher[br]envisioned the ideal society

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by examining concepts [br]like justice, truth and beauty.

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

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with their backs to the entrance,[br]unable to turn their heads,

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and with no knowledge [br]of the outside world.

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Occasionally, however, people [br]and other things pass by the cave opening,

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casting shadows and echos onto the wall[br]the captives face.

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The prisoners name [br]and classify these illusions,

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believing they're perceiving[br]actual entities.

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

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The light hurts his eyes and he finds[br]the new environment disorienting.

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When told that the things [br]around him are real,

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

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The shadows appeared much clearer to him.

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But gradually, his eyes adjust

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until he can look [br]at reflections in the water,

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at objects directly,

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and finally at the Sun,

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

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The prisoner returns to the cave[br]to share his discovery,

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but he is no longer used to the darkness,

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and has a hard time [br]seeing the shadows on the wall.

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

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and violently resist [br]any attempts to free them.

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Plato introduces this passage[br]as an analogy

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

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Most people are not just comfortable[br]in their ignorance

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but hostile to anyone who points it out.

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In fact, the real life Socrates[br]was sentenced to death

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by the Athenian government [br]for disrupting the social order,

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and his student Plato [br]spends much of "The Republic"

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disparaging Athenian democracy,

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while promoting rule by philosopher kings.

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With the cave parable,

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

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to govern themselves.

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But the allegory has captured[br]imaginations for 2,400 years

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because it can be read in far more ways.

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Importantly, the allegory is connected[br]to the theory of forms,

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developed in Plato's other dialogues,

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which holds that [br]like the shadows on the wall,

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

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such as roundness, or beauty.

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In this way, the cave leads to many[br]fundamental questions,

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including the origin of knowledge,

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the problem of representation,

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and the nature of reality itself.

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

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For philosophers of language[br]viewing the forms as linguistic concepts,

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the theory illustrates the problem[br]of grouping concrete things

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under abstract terms.

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And others still wonder whether[br]we can really know

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

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As we go about our lives,

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can we be confident [br]in what we think we know?

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Perhaps one day,

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

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Will you break free to struggle[br]towards the light,

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even if it costs you [br]your friends and family,

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or stick with comfortable[br]and familiar illusions?

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Truth or habit? Light or shadow?

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

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There are lots of us down here.