Plato: “Allegory of the Cave”

Explanation and Analysis of the Document

The allegory is reported in Plato's Republic as a conversation between Plato's teacher, Socrates, and Plato's elder brother, Glaucon. The conversation, however, is fictionalized. Plato's dialogues are generally more like philosophical theme plays than courtroom transcripts of actual conversations. Yet the conversations are realistic in that they are by and large faithful to what a given character would have said in a given situation. Although scholars debate the extent to which the Socrates of Plato's dialogues corresponds to the historical Socrates, in the allegory at least Socrates uses what was likely his typical real-life style of argumentation, known as the elenchus. Socrates' elenchus is a method of argumentation that progresses through questions, somewhat akin to a modern-day lawyer's cross-examination of a witness. As Socrates speaks in the allegory, it is rare that he does not conclude his remarks in the form of a question.

It is essential to understand the concepts presented in the books of The Republic leading up to Book VII in order to grasp completely the “Allegory of the Cave.” In The Republic's opening books, Socrates has formulated two definitions of justice that inform each other: one for justice as it operates in society and the other for justice as it operates in the individual. In both cases, Socrates argues that justice is a sort of threefold harmony, a mutually beneficial ordering. In society this consists of a harmony between rulers, guardians (a sort of auxiliary military class), and workers, where each class, in effect, “minds its own business,” performing the task it is most naturally suited for without meddling in the affairs of the others. In the individual there is a corresponding harmony between reason, emotion, and appetite, with reason ruling over the other elements of the mind.

Just prior to the “Allegory of the Cave,” Socrates is considering, in Book VI, how the rulers of the ideal city, who should be philosophers and kings alike, are to be trained. He argues that the most important part of their education is to understand the Form of the Good, that is to say, the idea of goodness as it exists purely in an abstract sense, not merely as a descriptive term or mental category. Socrates defines the Form of the Good as that which causes everything that partakes in it to be beneficial and useful; naturally, such a Form is important to consider for the ruler of a perfectly just society. What exactly Socrates means by “Form” is not entirely clear. Consider the example of the Form of Roundness. There are many things that are round: tires, pizzas, hula hoops, coins, and so on. While all these round things are distinct and numerous, there is one thing—the Form of Roundness—that unites them. Indeed, Socrates goes so far to argue that the Forms exist beyond their specific manifestations in such things as pizzas and hula hoops and, in fact, cause these things to be round in the first place. Moreover, as can be demonstrated easily, the existence of the Forms is not dependent on the individual objects that partake in them. Indeed, it is quite the opposite. A round pizza can be eaten, yet Roundness still exists in many other things. In short, then, the Forms are abstract entities, grasped only by the mind, which give rise to everything else in reality.

In order to explain more clearly the Form of the Good, Socrates discusses it by way of analogy, comparing the sun to the Good. He compares the way in which the eye perceives sensible reality—physical objects—to the way the mind perceives intelligible reality—the Forms, the very ideas of “good,” “just,” “round,” and so on. The analogy is fourfold: First, the eye can see physical objects because of the sun's light, just as Forms can be “seen” or are intelligible to the mind because of the “light” of the Good. Second, a physical object's qualities—for example, grass being the color green—cannot be perceived in the absence of the sun's light, just as the qualities that Forms have are unintelligible without the Good. Third, the sun is visible, just as the Good is intelligible. And, fourth, the sun causes physical objects to grow but does not grow itself, just as the Good generates the Forms but is itself not generated.

To further explain his analogy, Socrates proposes setting forth visible and intelligible reality on a “Divided Line.” Along the visible portion of the line are objects—things like trees and statues—as well as images, or copies of objects—things like reflections and shadows. Visible reality is illuminated by the sun and can give the observer only a limited understanding of full reality. The best that visible reality can offer someone is an opinion (perhaps faulty, as derived from perception), that is, something far short of actual knowledge as Plato defines it: an understanding not only that something is so but also why it is so. It is easy, after all, to mistake someone's face at a distance or to be fooled by an optical illusion. On the other hand, along the intelligible portion of the line, which is illuminated by the Good, actual knowledge is possible. In the intelligible realm reside things that the mind “sees” rather than things the body senses, objects of thought rather than physical objects. Here Plato locates concepts and the Forms themselves. Plato uses “concept” in a very limited sense to mean only mathematical and logical figures and ideas—things that help us gain access to and approximate the Forms themselves. An example would be the circle a student draws freehand in geometry class. He does not draw a perfect circle, of course, but by studying this circle, giving it abstract qualities that it does not possess (like perfect roundness) the student can gain insight into the nature of circles in general, that is, the Form of Circle. In this way, then, an analogy exists between the way in which we can learn about physical objects by seeing their shadows and reflections and the manner in which we can learn about the Forms by thinking about their “shadows and reflections,” or concepts.

Several important conclusions can be drawn regarding how Plato's ideas about the nature of reality and knowledge, as represented in the Divided Line, inform the “Allegory of the Cave.” First, the ways people interact with the visible and intelligible worlds are analogous but essentially different. Second, people “see” with both the eyes and the mind, but the clarity of the mind's eye is far greater than that of the physical eyes; the eyes can give perceptions of things, which yield opinions, but only the mind can give knowledge, which results when opinion can be rationally defended. Third, the visible world is one of becoming, subject to generation and corruption, but Forms simply always exist: They do not change, they do not come to be, and they cannot be destroyed.

The Prisoners of the Cave

To begin the “Allegory of the Cave,” Socrates asks Glaucon to imagine the state of people who are not educated, describing them as if they were chained in a dim, firelit cave in such a way that their eyes would be able to look only at the caves' walls. Onto these walls are cast images of imitations of actual things—statues of men and horses and the like—that have been paraded before the fire behind them.

Socrates seems to be drawing directly from the idea of the Divided Line. These prisoners have access only to the lowest part of the Divided Line: the images of imitations of actual things. Thus, the fire acts like the sun, illuminating objects—here, the statues—such that shadows are cast on the wall as images. The implication is that uneducated people have no ability to access ultimate intelligible reality and therefore cannot attain any real knowledge. Through their perception, they gain only vague impressions of things that are, in fact, false. Thus, with no knowledge of actual reality, including the Good (the sun), they are doomed to make poor decisions and pursue things that are ultimately neither useful nor beneficial.

Cave Ascent—Enlightenment

Socrates explains that since the inhabitants of the cave do not converse with one another and have such limited perception, they would naturally assume that the shadows before them are true reality. Socrates asks Glaucon to consider, then, what would happen if one of the prisoners were released from his bonds and compelled to stand up and look behind him. Socrates says that such a man would find this movement painful and would have difficulty seeing, owing to the brightness of the firelight before him. Although he would now have access to a truer version of reality, he would cling to what was familiar and would be extremely distressed and annoyed by such repositioning.

Socrates is commenting on the nature of perception and reality and the difficulty of education. People cling to that which is familiar to them. If they think they have already reached the truth, they are naturally prejudiced against new ideas, against any alternate versions of reality. While education is a means of teaching people how to see the world more clearly, the brilliance of the truth is such that it is not easy for the mind's eye to adjust. Education is uncomfortable; it is difficult. The way out of the cave is described by Socrates as “rugged” and “steep.”

Socrates next describes the prisoner as confronted with the light of the sun. Here he is blinded further and so chooses to look toward that which is familiar. For example, instead of looking at the trees themselves, he gazes at their shadows. Finally, he is able to consider the sun itself in its “own proper place” and deduce it to be the reason why he can perceive everything in the first place. Thus, in terms of the Divided Line, the former prisoner is moving from the perceptible world to the intelligible world. The sun seen by the prisoner corresponds to the Good of the Divided Line, while the tree and its shadow correspond to the Form and concept, respectively.

Cave Descent—The Paradox of Leadership

In his newly enlightened state, the former prisoner would consider himself happy but would feel pity for those still inhabiting the cave. He would even possess a certain contempt for them and would have no interest in participating in their false reality. Socrates introduces a paradox of leadership, claiming that although someone who is enlightened would have no interest in ruling, such a person must do so, as he is the most fit for such service. Socrates draws an implicit analogy between ascending from and descending into the cave. Just as it is difficult and unpleasant to leave the cave to be educated, it is equally difficult and unpleasant to return again as an educator or ruler. Nonetheless, the prisoner has a duty to improve himself, while the philosopher has a duty to improve others. In this section, Plato's Socrates perfectly meshes the two overriding concerns of The Republic, those of creating the ideally ordered—that is, wholly just—individual and society. The key is education. Education orders the mind properly, making reason the ruler of the individual; in turn, educated individuals ought to serve as rulers of society as a whole. In the analogy between the just harmony of society and the just harmony of mind, the ruler corresponds to reason, which rules the mind, while the guardian and worker correspond to emotion and appetite, respectively.

Socrates imagines what would happen to the unbound prisoner should he return to the cave. As his eyes would not be adjusted to the dim light, he would have trouble seeing the images cast on the cave wall as clearly as the current prisoners could. He would therefore become a laughingstock; the inhabitants of the cave would ridicule him, saying that his eyes had been corrupted by leaving the cave. They would mock the very idea of leaving the cave and would even threaten violence against anyone who would compel them to leave. Socrates reiterates how appealing it would be for an enlightened human being to spend all of his time in the world above and how absurd things like common law courts would seem to such a man, as they are controlled by those who have seen only false representations of the just, never the Form of justice itself.

In having Socrates discuss how violent the unenlightened masses' reaction would be to an enlightened man, Plato is likely alluding to Socrates' trial and death in 399 BCE. In his dialogues with other Athenians, Socrates roused their anger because he revealed the full depth of their ignorance, their pretenses to actual knowledge. While the men Socrates questioned would assume they had some definite knowledge, in testing their opinions Socrates would always find them to be contradictory or in some way incomplete, certainly far short of actual knowledge of the truth. Just as with the prisoners in the “Allegory of the Cave,” many Athenians were unwilling to be disturbed from their mental slumber by Socrates, the self-described gadfly of Athens, and thus reacted violently to his attempts to enlighten them.

The Nature of Knowledge and Education

Socrates reminds his listeners that with respect to darkness and light there are two kinds of blindness: that of moving from dark to light, such as in coming out of a windowless room at midday, and that of moving from light to dark, such as in going into a dark closet from a well-lit room. He argues, based on the natures of blindness, that the process of education must be considered in a novel way. Education has traditionally been understood as a process of putting knowledge into someone's mind, just as if someone could put sight into blind eyes. Socrates argues instead that education ought to be understood as a sort of conversion or turning. Just as sight is restored by turning toward the light, intelligence comes about by turning the mind toward a contemplation of the Good. Sight is a power that inherently exists in the eye; it simply must be directed away from shadows and toward the physical objects that are illuminated by the sun's light. In the same way, intelligence inherently exists in the mind; it only has to be directed away from mere perception and toward that which is illuminated by the Good (the Forms). Thus, just as an eye turned away from light is equivalent to blindness, a mind turned away from the Good is equivalent to ignorance. And just as clear sight is a result of the eye's being turned toward light, knowledge is a result of the mind's being turned toward the Good.

According to the “Allegory of the Cave,” knowledge is not something that is added to the mind but something that the mind turns toward. By its very nature, the mind has the potential to seek true knowledge; the mind actualizes that potential in being directed toward its proper object, the Good, the source of all that is useful and beneficial. Men are trained to have sharp perception to satisfy desires that serve the body, for example, food and sex. Socrates argues, however, that through education, ideally in earliest childhood, people can learn to direct their will toward things that satisfy the mind instead, for instance, truth and knowledge.

The Duty of Philosopher-Kings

Socrates next reiterates his argument that only those who have gazed upon the truth and the Good are fit to be rulers. Being unwilling to take on this duty, however, these men must be persuaded to go down again among the prisoners of the cave to share in their labors and honors. Society, Socrates argues, does not exist to serve any one person. Ideally, society operates as a harmonious or just whole in the best interest of all its members. Once one has struck a harmonious union in his own mind, with reason as ruler over the emotions and the appetite, it is that person's duty to descend once again into the cave, as painful as that may be, in order to benefit the rest of society. Socrates imagines how he could persuade those who are enlightened to fulfill their duty as rulers. He warns of the destructive nature of politics as it is practiced now, saying that if lovers of honor continue to act as rulers, no harmony or justice is possible.

It is interesting to note that history has no record that Plato himself took an active role in Athenian politics. Naturally, one could argue that he chose to fulfill his own duty to society by writing dialogues like The Republic. Perhaps Plato also feared that his life would be in danger if he participated in Athenian politics, especially given the trial and death of his mentor, Socrates. At any rate, in Plato's defense it is important to recognize his attempt at educating an actual philosopher-king in the person of Dionysius II, tyrant of Syracuse. The extreme instability of the Athenian political system during Plato's lifetime, not to mention its democratic structure, likely made the hope of a similar attempt in Athens impossible and unrealistic. Plato himself discusses his disillusionment with Athenian politics in The Seventh Letter.