Allegory of the cave
| Thinking hard|
or hardly thinking?
|Major trains of thought|
|The good, the bad|
and the brain fart
|Come to think of it|
Plato recounts the allegory of the cave in The Republic to illustrate his conception of the nature of truth. In the allegory, Plato describes a group of prisoners who have spent their entire lives in a darkened cave. The prisoners can see the wall of the cave which has shadows intentionally cast on it by puppeteers. The prisoners' knowledge of the world is limited to these shadows on the wall. One of their number escapes and sees the sun in the outside world for the first time, which nearly blinds him. Plato supposes that, should the freed prisoner return to his fellow captives and attempt to describe the outside world, the disability that he has sustained in discovering it would cause them to react to his new "reality" unfavourably and with suspicion.
The allegory describes Plato's conception of reality. Humans appreciate everyday objects through their senses; however, those objects are only "shadows" of the true "forms", a concept Plato develops throughout his writings. Knowledge of the forms is the equivalent in the allegory of being released from the cave and seeing the world itself rather than mere shadows of the world.
Plato essentially believed that there are four "levels" of knowledge. Speaking allegorically, the first one is the shadows of the objects the prisoners see; the second is the objects themselves seen in the dim light of the cave; the third is the objects seen in clear daylight; and the fourth is an up close examination of the objects. The former two stages are considered 'below the line' and the latter are 'above the line'
Plato believed that each of these stages is directly analogous to a state of knowledge of anything in the real world. Take the concept of a circle for instance, a primitive understanding involves a crude and rough outline of a shape similar to a circle. At this level, The next understanding would involve an ability to draw the circle with a compass. The first stage above the line involves knowledge of all the formulae involved with the circle and pi and trigonometry etc. The last stage is the form of a circle, from which all other understandings derive. As humans, Plato assumed we are not capable of reaching this level of understanding.
Plato applies his own allegory
Now all of this is only moderately interesting until we examine the book we find the allegory in - The Republic. The Republic is actually a work that analyzes a subject, namely justice, through these four levels of knowledge and provides an analysis at all stages.
In the opening stages of The Republic, Socrates (Speaking for Plato) asks what the definition of justice is. Cephalus gives a rather basic answer - "speaking the truth and repaying debts". Socrates is able to demolish this argument as extremely inadequate through the use of counterexamples. Polemarchus improves the argument somewhat, but the argument is clearly inadequate due to its reliance on fixed and definite rules. This is the primitive notion of justice, simple and sufficient for simple societies, but as a society develops, more is required.
Next, Thrasymachus enters the discussion and gives an essentially Nietzschean argument that "Justice is nothing other than the will of the stronger". Well, agrees Socrates, the argument is certainly better and achieves a certain level of sophistication more appropriate for a more advanced society.