The Allegory of the Cave
A group of people have lived in a deep cave since birth, chained and having never seen the light of day. They are bound so that they cannot look to the side or behind them, only straight ahead. Behind them is a fire, and behind the fire is a partial wall. On top of the wall are various statues, which are manipulated by another group of people, lying out of sight behind the partial wall. Because of the fire, the statues cast shadows across the walls the prisoners are facing. The prisoners watch the shadows act out stories. However, because they have seen nothing else but these shadows, they take them for reality. This is a reference back to the allegory of the line: the prisoners are on the lowest stage, imagination.
A prisoner is freed from his bonds, looks back, and sees the fire and the manipulated statues. He begins to understand that the statues are the reality. This refers to the belief stage in the line allegory: he takes the statues and fire as the most real things because they are they only things he sees. However, when he is dragged out of the cave, he realizes the world has greater realities than statues.
The light dazzles his eyes, and at first he can only see shadows. As they adjust, he can see reflections and then the objects themselves. This is the thought stage in the line allegory: he can see the real objects in their Forms.
When his eyes adjust further, he can look up at the sky toward the sun to see that the Sun is the cause of the existence of everything around him. Based on the Sun Allegory, the sun is the Form of Good, and, based on the line allegory the former has reached the final stage: understanding.
Because the goal of education is to spread it to others, the man tries to drag his friends out of the cave. Instead, they call him a fool and eventually stone him.
Socrates’ overall point is that educating people with the right natures is the priority of the city. Otherwise, people who are sharp and clever, could become wicked men instead of philosophers if they turn their talents toward something evil. Therefore, education is not putting knowledge into the soul, but steering the soul toward right desires.
What distinguishes the philosopher-king from everyone else is this: He knows the Form of Good and understands everything.
In order to supplement the general education, Socrates feels that in order to produce a philosopher king, educators must teach him mathematics and philosophical dialectic, because these two subjects draw the soul from the “cave.”
In order to choose philosopher-kings, you must find the children with the right natures (stable, courageous, grace, quick-learners, good memory, hard-working, and virtuous). These children will be cultivated and nurtured by being taught through play. Those who love mathematical study should be allowed to display enjoyment so they will apply themselves. This study will continue for five years. Then they will go and hold offices “back in the cave” and be tested in loyalty and steadfastness. After 15 years, at age 50, the best person will grasp the Form of Good and become the philosopher-king. He is charged with the task of educating the next generation.