Plato doesn’t tell us how it happens, but one of the prisoners becomes unfettered. It’s curious how involuntary the process he describes is, especially in its beginning phase, as if someone on the road to knowledge resembles a resentful teenager being dragged on a family outing and determined not to enjoy himself.
When one of them was freed and suddenly compelled to stand up, turn his head, walk, and look up toward the light, he’d be pained and dazzled and unable to see the things whose shadows he’d seen before. What do you think he’d say, if we told him that what he’d seen before was inconsequential, but that now—because he is a bit closer to the things that are and is turned towards things that are more—he sees more correctly? Or, to put it another way, if we pointed to each of the things passing by, asked him what each of them is, and compelled him to answer, don’t you think he’d be at a loss and that he’d believe that the things he saw earlier were truer than the ones he was now being shown?
Much truer.
And if someone compelled him to look at the light itself, wouldn’t his eyes hurt, and wouldn’t he turn around and flee towards the things he’s able to see, believing that they’re really clearer than the ones he’s being shown?
He would.
And if someone dragged him away from there by force, up the rough, steep path, and didn’t let him go until he had dragged him into the sunlight, would he be pained and irritated at being treated that way? And when he came into the light, with the sun filling his eyes, wouldn’t he be unable to see a single one of the things now said to be true?
He would be unable to see them, at least at first. (515c–516a)
Glaucon’s “at least at first” is a necessary qualification, since gradually the escaped prisoner will be able to see extra-cavernously, but only slowly and by degrees. Recovery from ideology—deprogramming as we now call it—takes time. His eyes can’t take in everything at once, because they have to adjust to the light. First he will simply look at images and shadows and reflections in water. Next he will be able to look at “the things themselves” (516a). Gradually he raises his eyes upward, studying the nighttime sky. Finally, his eyes will have adjusted sufficiently for him to see “the sun itself, in its own place, and be able to study it.”
The various levels, both within the cave and without, represent levels of being in Plato’s metaphysics.14 These levels are ordered by the relations of explanation, of accounts, of logoi. One ascends to a higher level by explaining the level one has already secured. This is how the process of knowledge proceeds, by what philosophers call abduction, or inference to the best explanation. Grasping the best explanation is the job description of reality-discovering reason. It’s the way that ontology can be expanded. Whether it is employed in theoretical physics15 or in philosophical reasoning, it’s by means of abduction that one can come to know the reality that isn’t passively received, in either imagination or perception, whether that reality is of quantum fields or, as Plato would have it, a value-saturated reality, structured by the confluence of the True-the Beautiful-the Good. The expert knower, whether he’s a cosmologist or a metaphysician, is discovering objective reality by seeking the best explanation (and as Plato points out in the Timaeus [29c–d; 44d], this form of knowledge is probabilistic at best, always prepared to give way to a better explanation).
What compels us to ascend to another level are the questions posed at the level we are at. We only know where we have been after we have left it. It’s our pursuit of explanation that pushes us along. At the first level of the cave, we understand that we’ve been looking at shadows only when we see the shadow-making operation that’s going on inside the cave, the ways in which everything was elaborately rigged in there to create the illusions we took for real. One only understands that one has been living in a subterranean cave when one exits it, leaving behind the constructed values of a society imprisoned by its ideology with all its ruses designed to keep the prisoner from making contact with what is out there—in other words, reality. Climbing upward and exiting the cave is stepping outside ideology, terrifying and painful at first, but liberating and natural at the end, so that the thought of returning to the abandoned ideology becomes unthinkable. “I would suppose he would rather suffer anything than live like that” (516e). Exiting the ideological cave, where all our questions are answered and everyone we know agrees with us—“I say to you now, knowing full well that you will agree with me … only if you already agree with me”—is the hardest and most significant step we can take. But if we don’t take that step, then we will leave this life no closer to the truth than when we entered it. And that is exactly what it is to live a life not worth living, even if it proves to be the most pleasant sort of existence.
Still, there are many levels still to be achieved outside the cave. Plato enumerates the extra-cavernous levels: images and reflections, the things themselves, the sun. What do these signify? His Analogy of the Divided Line (509d–513e) is the key. The images and reflections correspond to mathematics, the various branches of which Plato has his guardians of the Republic spend several decades mastering. The things themselves are the forms, those abstract theoretical entities that Plato believes, at least at this stage of his philosophical thinking, are necessary to explain the identities of concrete particulars.
But the trail of explanations doesn’t hit a dead end, not even here, in this theorized domain of abstractions so far from common sense. Not even the intelligible forms are self-explanatory. There is a structure to this abstract domain—not all possible forms exist, some entail others, some exclude others. A complex structure is superimposed over this abstract domain. The abstract forms and their relationships with each other give reality the shape it has. But why is it this shape rather than another? Why is it anything at all?
A further ascent is required, to the form of the good. In the Myth of the Cave, this last ascent is reached when the former prisoner, now enlightened, casts his eyes up to the heavens and beholds the source of light itself, the sun, and the language becomes appropriately heated. “In the knowable realm the form of the good is the last thing to be seen, and it is reached only with difficulty. Once one has seen it, however, one must conclude that it is the cause of all that is correct and beautiful in anything, that it produces both light and its source in the visible realm, and that in the intelligible realm it controls and provides truth and understanding, so that anyone who is to act sensibly in private or public must see it” (517b).
Plato, in the Republic, is firmly on the side of the Reasonables. Everything we need to know—intellectually and morally—is out there, and the way we come to see what is out there is no more private and unshareable than the reality itself is. One proceeds by way of reason, by offering the best explanations for the questions that each level presents. An anonymous, allegorical knower stands in for any of us, so allow me to change the gender of the pronoun. The knower doesn’t come with any special cognitive equipment of a kind to make her privy to special messages from outside the cave. It’s on the power of her own reason that she achieves the vision of the sun. Not only is this a path that is, in principle, open to anyone, but it is a path that requires collaborators, since judging what is the best explanation is an activity best done with others, as the man who founded the Academy, gathering the best thinkers of his day there to join him, must have believed. The prisoner was herself first freed and dragged forward on the first leg of her trip by someone else, and once she sees the sun she remembers the prisoners still fettered in the cave and pities them, returning to help them make the ascent that she has achieved. (It doesn’t necessarily end well. Prisoners of ideology don’t necessarily welcome liberation.)16
The form of the good, of agathon, is the place where all explanations stop. It is the level of the self-explanatory. There must be such a level of the self-explanatory, if reality is, as Plato has assumed it to be, thoroughly intelligible. There are no brute contingencies, facts which are facts for no other reason than that they are facts. E
xplanations must penetrate the whole of what is. It’s not turtles all the way down, but rather reasons, logoi, all the way down. This is the fundamental intuition of the rationalist; it was picked up again in the seventeenth century by such hard-core rationalists as Spinoza and Leibniz. Leibniz named it the Principle of Sufficient Reason.
Like them, Plato has demanded that reality thoroughly account for itself, every step of the way, and this entails that there must be a level of the self-explanatory. The way we ascended to each next level was to judge (as best we could) the best explanation. We’ve been led, every step of the way, by the intuition that the best explanation—the most beautiful, the most elegant—is the right explanation. The good is simply that intuition affirmed. Reality is what it is because it realizes the best of all possible explanations. This is the Sublime Braid—the True-the Beautiful-the Good. The structure of the world is shot through with a sublimity so sublime that it simply had to exist. Reality exists because it, too, is striving to achieve an existence worth the existing. The cosmos itself is a high achiever, and existence is the prize.
Plato has, in his explanatory ascent, implicitly posed the fundamental question of metaphysics: Why is there something rather than nothing? Leibniz is customarily credited with first explicitly formulating the question, and in those very terms, but, once again, Plato got there first (and Spinoza certainly beat Leibniz to it as well).17 Plato implicitly posed the question by explicitly proposing his answer. The good is what bestows existence, he tells us in the Republic. Agathon binds the structure of reality—whatever that reality might turn out ultimately to be. (In the Timaeus, he voices skepticism that we can ever know it in its entirety. Reality’s being intelligible doesn’t entail its being intelligible to us.) Plato is open to reality’s turning out to be quite different from the way we conceive it at any point in our joint adventure to figure it out. The self-questioning is of the essence of the rational process. But what he holds firm to is that whatever reality turns out to be like, it is like that because the best of reasons makes it so, and we are led to those best of reasons by our own sense of intelligibility-maximizing beauty: “Both knowledge and truth are beautiful things, but the good is other and more beautiful then they” (508e).
The Myth of the Cave consigns anything that cannot give an account of itself—including whispers in one’s own privileged ears from one’s own private oracle—to the interior of the sooty cave. It is, in the end, hostile to the Unreasonables, who have to be placed at the level of eikasia, prisoners of ideology, unable to give a logos. Inferences to the best explanation are put on the seminar table, there for all to evaluate—not just in philosophy but in all theoretical domains (except mathematics, where conclusive proofs are possible). Inference to the best explanation captures what it is to theorize.
The word “best” is overtly evaluative. There is no escaping evaluation, no more in deciding what is rational to believe than in deciding what is ethical to do. The fact that evaluation is involved—different people may disagree on what constitutes the best of the available explanations—makes it all the more imperative to expose one’s reasoning to a multiplicity of perspectives. When I had Plato say to Roy McCoy that he would rather be refuted than to refute, I was quoting him verbatim.
But what criteria are to be used in evaluating which are the best explanations? Here, too, disagreements erupt. We might ask: Is an explanation that increases the sense of mystery in the world to be valued over one that decreases the mysterious, or is it the other way round? There are excellent reasons, well argued and generally accepted, for embracing the latter alternative. In fact, precisely because the explanation that decreases mystery is judged the better explanation, Plato’s own explanation of universals in terms of the abstract forms has been dropped in favor of other explanations. His so-called Theory of Forms created more mysteries than it solved. There’s evidence that he himself drew the same conclusion as a result of the battery of criticisms he lodged at the theory in the Parmenides. In the Timaeus and the Laws, the most intelligible—and therefore beautiful—of the forms are conceived of in terms of mathematical structures, other forms dropping away.
The demiurge of the creation myth presented in the Timaeus created the physical universe as a living organism, imparting a soul to it and infusing it with as much eternity as it is possible for a time-dwelling entity to enjoy. The infusion comes about by making time itself an image of eternity. Unlike the truly eternal, the universe is in motion, but its motion is subtended by the law of number, which means it partakes, as best it can, of eternity. It’s the mathematical motions within the cosmos that itself generate time, the image of eternity.18
So, as the model was itself an everlasting Living Thing, he set himself to bringing this universe to completion in such a way that it, too, would have that character to the extent that was possible. Now it was the Living Thing’s nature to be eternal, but it isn’t possible to bestow eternity fully upon anything that is begotten. And so he began to think of making a moving image of eternity: at the same time as he brought order to the universe, he would make an eternal image, moving according to number, of eternity remaining in unity. This number, of course, is what we now call “time.” For before the heavens came to be, there were no days or nights, no months or years.… These all are parts of time, and was and will be are forms of time that have come to be. Such notions we unthinkingly but incorrectly apply to everlasting being. For we say that it was and is and will be, but according to the true account only is is appropriately said of it.… And all in all, none of the characteristics that becoming has bestowed upon the things that are borne about in the realm of perception are appropriate to it. These, rather, are the forms of time that have come to be—time that imitates eternity and circles according to number. (37c–38b)
The mathematics inscribed in the heavens’ motions, giving us time, also, in the Timaeus, generate the structure of matter. Reason saturates the cosmos in the form of mathematics, which not only allows the world of was and is and will be to partake in the everlasting is, but also renders the cosmos accessible to our mathematical reason. Our saving virtue is that our human reason can penetrate the cosmic reason:
And when reason which works with equal truth whether she be in the circle of the diverse or of the same—in voiceless silence holding her onward course in the sphere of the self-moved—when reason, I say, is hovering around the sensible world and when the circle of the diverse also moving truly imparts the intimations of sense to the whole soul, then arise opinions and beliefs sure and certain. But when reason is concerned with the rational, and the circle of the same moving smoothly declares it, then intelligence and knowledge are necessarily achieved. (Timaeus 37b–c, translation by Benjamin Jowet)
It’s no wonder that Galileo and Kepler were passionate Platonists. Since the time of Thomas Aquinas, the Church had favored Aristotle. And whom the Church favors it becomes heresy to challenge. But it is Plato, particularly the Plato of the Timaeus, who is made to carry the spirit of rebellion that rose up in the sixteenth and seventeenth centuries against the dogmatized Aristotelian teleology. Finding their way back to Plato, the new physicists seize on mathematics as the very soul of explanation—and the more beautiful the mathematics, the more explanatory value it is judged to have. If the Aristotelian/Ptolemaic geocentric system is rejected, it isn’t on the basis of observation alone—the epicycles can accommodate all the observed motions of the planets—but because the epicycles are mathematically hideous. Make the sun the point of origin around which the earth and planets revolve and the mathematics becomes beautiful. Plato’s aesthetic realism profoundly affected the men who created modern physics, and both Galileo and Kepler often mention the “divine Plato,” using Plato’s criteria for judging the best of explanations as their own.
Inference to the best explanation is inescapably value-laden, but then so, too, in Plato’s scheme of things, is reality. The positioning of agathon at the apex of the prisoner’s vision means that there is som
ething inherently superior about reality as it is that dictates that this is the reality that had to be. Agathon entails that reality can ultimately give an account of itself, which doesn’t mean that we, mere humans, will ever be able to arrive at that ultimate accounting. But by Plato’s lights, we can trust that the accounting exists. Trusting that it exists can be regarded as a part of the metaphysics of physics, on the basis of which enormous expansions of ontology have been argued, among which none could be more expansive—could it?—than the controversial notion of the multiverse. The physicist Brian Greene wrote an article in The Daily Beast, explaining the current thinking (of which he’s a fan) according to which our universe is only one of a vast number of universes, which are composed of different particles and governed by different forces. How vastly many? According to string theory, “the tally of possible universes stands at the almost incomprehensible 10500, a number so large it defies analogy.”19 Allowing mathematical elegance to carry us along has gotten us far beyond the cave. Who knows? Perhaps we’ll someday be able to answer why our universe—whether a multiverse or not—had to be exactly as it is. And if we do, it will be because of Plato’s intuition that, when it comes to the universe, it’s reasons all the way down, and that’s what’s so good about it. That’s why agathon is sovereign.
Plato at the Googleplex Page 49