Plato's philosopher-king
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Among the greats of ancient Greece was Plato, and among the classics of philosophy is his Republic.

Plato, born in Athens around 427 B.C., began his career as a politician and, inspired by the controversial Socrates, ended as a philosopher. His Republic focused on defining justice; another prominent theme was the philosopher-king.

Plato describes the philosopher with the allegory of the Cave. He envisions humans as prisoners chained in a cave, forced to stare day after day at a wall. On a roadway behind the prisoners figures pass, casting shadows on the wall that the prisoners face by the firelight beyond them. By this lifetime experience the prisoners conclude that “truth is nothing other than the shadows of artificial things” (515c). One day, one of the prisoners is dragged out of the Cave and into the lighted world. After a moment, the freed prisoner’s eyes adjust to the light, and he realizes that the shadows he saw were only imitations of Forms.

Plato's cave
Image credit J. Legaers (?)

To understand Plato’s theory of Forms, or Ideas, consider a tree. How do we know a tree is a tree? Is it the leaves? the bark? the height? No two trees are alike; a pine tree is certainly not like a maple. How, then, does society even agree on what makes a tree, a tree? According to Plato, we know a tree to be a tree because we possess abstract conceptual knowledge of the ideal tree. We match what we see to an idealized representation – the Form – and if it matches, then it is a tree. (I discuss Forms a little more in this post on the definition of beauty.)

The theory of Forms embraces an essentialist view of reality, which believes that X is X because it has innate attributes that make it X. This contrasts nominalism, which supposes that objects have no objective reality and exist only because society identifies them by name. This view implies the absence of an actual tree and the presence of words alone.

The Cave allegory casts philosophers as the men freed from the Cave who have beholden the Forms and understands that what “common” men see are but imitations of them. He describes this revelation as the “soul’s journey up the intelligible place” (517b). Thus enlightened, the ex-prisoner rushes back to the Cave to tell his friends, but they do not believe him, having not seen the light themselves. Thus, the philosophers, if they cannot lead the men to the light, might at least lead them.

The School of Athens Raphael
The School of Athens, by Raphael (16th century)

Of course, not just any man can be a philosopher. Education, which turns the soul toward the light of learning, cultivates virtues of the soul that the state should begin developing in suitable candidates from childhood. Repeated exposure to or imitation of practice changes our characters, so Plato hypothesizes that if men are exposed or encouraged to imitate in youth the qualities and actions of an orderly and courageous man, then they will regard such conduct as normal and thus adopt it. Thereby the right and good becomes normal, which opinion prepares a man for philosopher-kingship.

Plato concluded his argument, “So our city will be governed by [philosophers] with waking minds, and not, as most cities now which are inhabited and ruled darkly as in a dream by men who fight one another for shadows and wrangle for office as it that were a great good, when the truth is that the city in which those who are to rule are least eager to hold office must needs be best administered and most free from dissension” (520c, d). Theoretically, the philosopher-king would best govern society because philosophers have all the wisdom to rule and none of the self-interested ambition that would corrupt them.

What do you think about the idea of a philosopher-king? Is it legitimate or, as the cartoon at the beginning suggests, impractical?

To read Plato’s full Allegory of the Cave, see here.