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The Allegory of the Cave (circa 380 BCE)
Human beings spend all their lives in an underground cave with its mouth open towards the light. They have their legs and necks shackled so that they can only see in front of them, towards the back of the cave. Behind the prisoners, a fire is blazing, and between them and the fire there is a low wall behind which men carry diverse statues above their heads, such that the fire casts the shadows of the statues onto the back of the cave. Because these shadows all the prisoners ever see, they suppose that the shadows are the objects themselves.
If a prisoner is unshackled and turned towards the light, his eyes suffer sharp pains, but in time they grow accustomed to the light and he begins to discern the statues. He is then dragged out of the cave, where the light is so bright that he is only able to look, first at the shadows, and then at the reflections, of the actual objects. At last, he is able to gaze upon the objects themselves, of which the statues were but pale imitations. In time, he looks up at the sun, and understands that the sun is the cause of everything that he sees around him, of light, and sight, and the objects of sight.
The true purpose of education is to drag the prisoner as far out of the cave as possible; not merely to instil knowledge into his soul, but to turn his whole soul towards the sun, which is the Form of the Good. Once freed, the prisoner is reluctant to go back down into the cave and involve himself in the menial matters of men. When eventually he does, his vision is no longer accustomed to the dark, and he seems ridiculous to other men. Nonetheless, he must be made to return into the cave and partake of human labours and honours, because the State aims at the happiness not of a single person or class but of all its citizens. Moreover, he has a duty to give service to the State, since it was by the State that he was educated to see the light of the sun.
Quoting from Book VII of the Republic:
The State in which the rulers are most reluctant to govern is always the best and most quietly governed, and the State in which they are most eager, the worst ... You must contrive for your future rulers another and a better life than that of a ruler, and then you may have a well ordered State; for only in the State which offers this, will they rule who are truly rich, not in silver and gold, but in virtue and wisdom, which are the true blessings of life ... And the only life which looks down upon the life of political ambition is that of true philosophy. Do you know of any other?
Discussion
What if we are being radically deceived? What if I am no more than a brain kept alive in a vat and fed with stimuli by a mad scientist? What if my life is nothing but a dream or computer simulation? Like the prisoners in Plato’s cave, I would be experiencing not reality itself, but a mere facsimile or simulacrum of reality. I could not be said to know anything at all, not even that I was being deceived.
Which would you prefer: a life of limitless pleasure as a brain in a vat, or a genuine, human life along with all its struggle and suffering? Most people actually opt for the latter, suggesting that we value truth and authenticity and, by extension, that we value knowledge for its own sake, as well as for its instrumentality.
But even if we are not being radically deceived, it is not at all clear that we can have any knowledge of the world. Much of our everyday knowledge comes from the use of our senses, especially sight. "Seeing is believing," as the saying goes. But appearances, as we all know, can be deceptive: A stick held under water appears to bend; and hot tarmac, when viewed from a distance, looks like sparkling water. Our senses are subject to manipulation, as, for example, when a garden designer uses focal points or clever planting to create an illusion of space. My mind interprets a certain wavelength as the color red, but another animal or even another person may interpret it as something entirely other, or perhaps not perceive it at all. A bat or a salmon experiences the world very differently to me. And what about you? How do I know that what I experience as pain is also what you experience as pain? You may react as I do, but that need not mean that you are minded like I am, or even that you are minded at all. All I might know is how the world appears to me, not how the world actually is.
But according to Plato, if we care enough about the truth, or are made to care, we may be able to apprehend the true nature of reality, by the use, not of our circumscribed, earth-bound senses, but of our free-ranging reason and intellect. This eagle-eyed perspective qualifies us to rule, but is so captivating, so bright and blissful, that we are reluctant to do so—preferring instead to hide out in our ageless gardens and libraries.
And yet we must stoop down and expose ourselves to the public glare, because, as Plato says, the penalty for refusing to rule is to be ruled by someone worse than yourself.
Read more in The Gang of Three: Socrates, Plato, Aristotle.
References
Plato, Republic, Bk VII, 514a–520a. Translated by Benjamin Jowett.
