This is our next-to-last session on Plato's Theaetetus. We are reading through 196c today. Where are we? We nearly defeated relativism last time, and there were several interesting arguments against it.
The first was the self-refutation argument: if everybody is right, then the people who disagree with you are right, which means you are wrong. Perhaps a little cheap, but interesting. The second argument got to the point about time: what about predictions? Aren't some people better predictors than others, better prophets? Socrates himself, at the beginning of the dialogue, proves to be a good predictor of how someone will turn out. That cannot be a matter of private perception alone; some people simply understand what is going to happen better than others.
Then there was an indirect argument that went the long way around, via Heraclitus. Knowledge as perception supposedly implies Heracliteanism: everything is changing, everything is altering its qualities at every moment, and therefore you cannot say anything durable. All your statements will be disproved in the next moment, and the very statement that knowledge is perception will disprove itself. It is an interesting argument, though perhaps not definitive, given how indirect it is.
Finally, we looked at the digression in which Socrates describes the philosopher as opposed to the legal man. I think we concluded that the "philosopher" depicted there is a caricature, someone who has his head in the clouds and is a complete nerd, and not really a portrait of Socrates himself, who is rather savvy about people. It is more a portrait of Theodorus, who is satirized here quite strongly. He is the one who does not know that he does not know; he is the one who cannot recognize individual human beings. In fact, he cannot even recognize himself in the mirror when Socrates holds one up to him and says, "Look at this man." It is a pretty funny passage.
We now arrive at the final argument against the idea that knowledge is perception, which begins at 184b. Socrates asks: "With what does a man see white and black? With what does he hear high and low notes?" The expected answer is that he sees with his eyes and hears with his ears, but Socrates immediately corrects this: strictly speaking, you do not see colors with your eyes.
Audience: You see colors through your eyes, and there is some unifying thing that brings together all the sensory information through which you experience the world, the soul, I think he says, and it is with that soul that you truly experience.
Exactly. The point is that the various streams of sensory data are gathered and unified by the soul, which is the true subject of experience.
Plato uses the word psyche, traditionally translated as "soul," but he says, "Call it a psyche or whatever you want to call it." He is not dogmatic about this, and no religious doctrine is necessarily implied. You could call it the psyche, the mind, the consciousness, or even the brain if you want to be materialistic about it, the frontal cortex, your CPU. Whatever you take to be doing the central processing is actually you. That is your consciousness.
And this central you is going through your eyeball, for instance, to see colors. We might as well add the other organs: through your nose, your tongue, your ears, and through your skin, which is, of course, almost your whole body, as the organ of touch. The point is that there is a central psyche that is actually having these perceptions and integrating them.
Plato says it would be a strange thing if there were a number of senses sitting inside us as if we were wooden horses. The allusion, of course, is to the Trojan Horse. After ten years of war, the Greeks left a wooden horse in front of the gates of Troy, and the Trojans were foolish enough to think it was a gift. They brought it inside the city walls, not knowing it was a hollow shell filled with the best Greek warriors.
In that case, the horse has no consciousness and no real unity. It is just an empty shell for independent agents thrown together. Your senses are not like that. It is not as though your eyes and your ears are simply tossed into a box together; there is a you who unifies them. This is genuine progress in the argument, and it leads directly to another very important premise at 185a.
Aristotle's claim is that what you perceive through one sense power, you cannot perceive through another. You can't hear colors, for instance, or see sounds. Let me represent this schematically: each sense organ discloses a certain domain, the visible, the audible, the olfactory, the gustatory, the tangible, and there is no overlap between them. Each has its own entirely separate domain.
But is this actually true? Consider a straightforward example: if a firework goes off close enough to you, you don't just hear it, you feel it. In some sense, you are feeling the noise. One could argue that these are really distinct sensations that are merely coordinated in experience, which is why we associate them so strongly. That is an argument, though not necessarily a convincing one. In modern terms, we would say it is the same source, a wave form, perceived in two different ways.
Another challenge to this view concerns smell and taste. These two senses are tremendously related; taste is apparently ninety percent smell, or perhaps the other way around. We can posit that they are different senses, but there does seem to be genuine overlap between them. A further counterexample involves shape. Take a cube: I can feel that it is a cube, and I can see that it is a cube. Do the senses in fact cross over here, or should we say those are distinct, separable sensations of a single object?
Audience: I was thinking of synesthesia originally. As far as I understand, that is more of a psychological confusion of different sensory inputs. It happens in the psyche rather than involving, say, actually smelling color.
My son has synesthesia, and especially had it when he was very young. He would say things like, "The number four is so shrill, and it tastes really sour, and it's all yellow." Exactly how that is happening is unclear, but there is clearly a great deal going on in that psyche. According to Aristotle's theory, one would still be taking distinct inputs, to use the language of computing, and combining them, so that they feel as though they are one and the same thing, even though they can be analytically separated out.
In normal life, we use all the senses available to us simultaneously; they are synchronized and coordinated, and we rarely need to distinguish what we are receiving from smell versus taste versus touch. But perhaps by paying careful attention, we can make those distinctions. Another illuminating case involves people who have been blind from birth and, as adults, undergo an operation that grants them sight for the first time. If you show such a newly-sighted person a cube and ask them what it is, they have no idea. They need to learn what a cube looks like. If you let them hold it, they will immediately say, "Of course, a cube." In fact, it is often easier for them to navigate by closing their eyes and using their cane, because processing visual imagery gives them a terrible headache.
The things that come so naturally to those of us with sight from birth are things we learned in infancy. We learned to coordinate all these sensory inputs, and they were not simply handed to us pre-integrated. If we grant, then, for the sake of argument, that what you receive through one sense you cannot receive through another, a great deal will hinge on that claim, and it is worth examining carefully.
What are we going to do about what Socrates calls the things that are common to more than one sensory domain? Consider the number two, which he mentions at 185B. You can see two hash marks, and you can hear two sounds, but can you see or hear the number two itself? One might say, "Sure, here's the number two right there." But that is not the number two; that is the numeral two, the Arabic numeral two. The argument is that you don't see the concept of two, and you cannot acquire that concept through perception.
This follows from the specialization of the senses: the senses are specialized and do not overlap. If the number two were something visible, it would never apply to sounds, since it would be valid only within the visual domain. Anything that can be applied to both the visible and the audible must therefore come from neither sight nor hearing.
Audience: Isn't this a distinction between a thing and a concept? I can say there are one or two glasses of water, but there is a concept of two that can be applied to a variety of different settings and doesn't require the senses.
That is very much in line with what Socrates is arguing. Theaetetus himself says he supposes the psyche must be working on its own, and this is the moment in the dialogue when Socrates apparently sincerely says, "I love you, you're beautiful, that's what I believe." He never forgets that Theodorus had called Theaetetus ugly; that keeps coming back.
The question then becomes: where do we get these concepts? They are easy to acquire, of course. A small child can normally learn to count one, two, three, four, and we teach this by means of sensory examples, such as two cherries or three cherries. Still, the number three is not a piece of fruit. Philosophy of mathematics can go in various directions: you are either discovering something in the intelligible realm, or perhaps you are simply carrying out a mental procedure. But in either case, the concept is not something handed to you by sensation.
Audience: Is the separability of these concepts from perception essential to the theory, or is it merely an entrée into a broader discussion?
I think it is essential, and we will see why when Socrates applies this to the concept of being, which is the key move. A true empiricist, someone who bases all knowledge on experience, would say that even if you do not directly perceive the number two, it arises through various sensory inputs that are combined or processed in some way. On this view, the concept ultimately comes from perception, and without perception the mind would be a blank slate.
Audience: But wouldn't that require multiple senses? Could I grasp the concept of two if it were coming from only one sense?
We do not have an explicitly empiricist theory of knowledge in this dialogue, so I would have to reconstruct one on the spot. An empiricist might argue that if you receive enough sensations from different sources, perhaps combined with action in the world, these concepts spontaneously arise, but they remain grounded in experience. A rationalist, to use a modern label, would say the opposite: these concepts do not fundamentally come from experience at all. They come from something mental, something that occurs within the psyche. On this view, we are actively contributing these concepts to experience and thereby shaping it.
Audience: That all makes sense, but I still do not understand why the separation of the senses was so essential to this argument.
Consider this: suppose the visual and the auditory overlapped significantly, so that you could hear colors and see sounds. Then any concept that applies to both colors and sounds could in principle have come from either your eyes or your ears, and you would have an empirical concept derived from experience through one of those two senses. If all the senses overlapped completely, if you could use any organ to pick up any perception, then you would not need the psyche at all to account for common concepts like number, because those concepts could simply enter through smell and apply to touch, or any such combination.
Audience: Is this essentially a conversation that takes place in the moment? Is that why it is so essential?
That is worth thinking about carefully. Socrates does go on to refer to time at 186C, where he notes that calculations regarding being and goodness "come when they do only as the result of a long and arduous development involving a good deal of trouble and education." So the theme of temporal extension does become explicit. The argument, I think, is about what can happen in an instant, and if something cannot happen in an instant, then it must occur not only within the psyche itself but over some extended period of development.
Audience: When Socrates makes that move into the psyche, it didn't seem to me that separating the senses was essential to get there. He makes a big deal of it, as though you cannot proceed without it, but I still don't quite understand why that separation is necessary.
Let's look at 185B. Socrates has mentioned several common concepts: being (both sound and color both are, or exist), difference, sameness, the numbers one and two, and the concepts of like and unlike. He then asks, "Now what is it through which you think all these things about them? It is not possible, you see, to grasp what is common to both, either through sight or through hearing." Why is it not possible? Because sight and hearing are distinct and do not overlap.
Audience: I feel like the separation of the senses might be a setup for the psyche, so that we can then arrive at the idea that there are concepts separate from the world. It feels like a stepping stone in the argument rather than something theoretically necessary in its own right, the psyche is so much larger that it overshadows all of this preliminary work.
There is a huge question lurking here: what exactly is this psyche? In a real sense, the entire subsequent history of philosophy is a footnote not just to Plato in general, but to these very pages. What is the complete list of these basic common concepts? Some philosophers call them categories. Can we compile a complete list? Is there a system to them? Where do they come from? Perhaps they do come from perception after all, in which case this argument fails. If they do not come from perception, how do we develop them, and by what right do we apply them?
That last question is Kant's central concern in the Critique of Pure Reason. Take causality as another major example: one thing causes another. Where does that concept come from? Do we have the right to assert that everything must be the result of some causal law? These are questions philosophers have struggled with ever since. Since this is meant to be an introduction to philosophy, I will leave it there for now, though we can certainly dig deeper if you wish.
The biggest question, the biggest topic, the biggest category that the argument hinges on is being, which seems to be something very simple. We say all the time, "Here's a book." How do you know? Well, I see it. But strictly, according to this argument, you do not see the being of the book. You see colors, shapes, and so on. Being is one of those concepts that you can apply to smells, sounds, textures, whatever. It must therefore be something that the psyche is developing on its own, which you then apply to your sensations in order to make a judgment: this exists, some object exists here.
This has become so natural and easy for us that we do it without ever reflecting on it. But Socrates is getting us to think about where we get this concept of being and what it even means. I quoted the passage where he says it takes a great deal of education, reflection, and perhaps a bit of luck to arrive at a good conception of being. The concept has also come up earlier in the dialogue, where Socrates, playing the role of Protagoras, argued that we must get rid of this very idea, because being suggests some sort of endurance and independent existence.
I think the point is broader than that, though. Whether or not you want to read those particular implications into being, we have some sense of what it means for things to exist, to be something rather than nothing. Whatever you mean by that, it must be something for which the psyche and judgment are responsible. Now, if knowledge has to be true, and that is assumed throughout this dialogue, since there is no such thing as false knowledge, then knowledge has to get to being. To reach the truth is to grasp how things are and that they are, and for that you need the psyche, because the concept of being is something the senses alone cannot possibly provide.
Socrates seems to genuinely believe this; he grows very enthusiastic about it. I suspect Plato believes it as well, and personally I find it convincing. If you are convinced too, then it seems we have finally defeated the idea that knowledge is perception, at least if by perception we mean sense perception.
The conclusion at 186e, at least in this translation, seems to go a little too far. Socrates says, "Perception has no share in the grasping of truth since it has none in the grasping of being." I checked the Greek, and I think this could be softened somewhat. One could say that it does not belong to perception, on its own and by itself, to get hold of truth. That formulation is perhaps a little safer.
To say that we have no need of perception at all seems rather absurd. Consider someone born with no sensations: such a person would never acquire any knowledge; they would simply be, as it were, a blob. That is a very different claim from the one Socrates is making. Many of these statements are open to a range of readings, but this particular one, as translated here, that perception has no share in truth, goes too far, in my view.
We can now make a distinction between perception and judgment. Previously, the dialogue used "perception" to cover both cases: seeing red, for instance, and also holding an opinion such as believing oneself to be wise. But the latter is not a perception. It necessarily involves the psyche, actively forming a thought rather than passively receiving sensations. So can we say that knowledge is judgment?
A distinction is drawn at this point: knowledge must be true judgment. That claim, knowledge equals true judgment, is held in place for a while, and then Socrates goes off on one of his tangents, asking how false judgment is even possible. That turns out to be a more interesting question than whether true judgment is knowledge, because true judgment is not knowledge, and a little reflection will show why.
What would be an example of a judgment, or opinion, or belief (the Greek word is doxa) that is correct or true, yet clearly not knowledge? Consider a scenario where one stumbles into the truth by chance. Suppose I have a broken clock, unaware that it is broken. I glance at it at 2:30 and form the judgment that it is 2:30. That judgment is true, because it really is 2:30, but did I actually know it was 2:30 simply because I looked at a broken clock? No.
In fact, we get lucky in our judgments far more often than we might think. As I walk down the street, do I absolutely know that the pavement is not some kind of hologram, that I am not about to fall into the sewer? I am taking it on faith. 99.99% of the time I will be right, but it remains a true judgment, not knowledge. In The Republic, Socrates compares true judgment without knowledge to a blind man stumbling down the right road: he is on the correct path, but he has no idea what is going on.
Audience: Like a multiple-choice test where you guess and happen to get it right — you didn't actually know the answer.
Exactly. That happens all the time, and it will in fact prove quite easy for Socrates to refute the claim that true judgment constitutes knowledge.
Being the wise midwife that he is, Socrates delays. He doesn't abort the baby right away — he lets it sit for a while and goes off on this tangent. Let's look at how Theaetetus introduces his second definition. This is 187B: "I rule out judgment in general because there is also false judgment, but true judgment may well be knowledge, so let that be my answer. If the same thing happens again, and we find as we go on that it turns out not to be so, we'll try something else." That seems very reasonable.
But notice that in saying this, Theaetetus has already provided a counter-example to the very thing he is claiming. He is essentially saying, "I don't know if I'm right, but this is my judgment, and I might have a true judgment — though I don't know." His judgment is that true judgment is knowledge. Yet in offering it this way, he has given us an example of what might be a lucky guess without knowledge, and in doing so he disproves himself.
The same thing happens — and I only noticed this on perhaps the seventeenth reading of this dialogue — when Theaetetus introduces knowledge as perception. He says, "The way it appears to me now, at any rate, is that knowledge is perception, but I don't know." In both cases, he is not quite clear on what it is that he is actually claiming, and each time he unwittingly undermines his own definition at the very moment he proposes it.
What else is needed? Let us anticipate the last part of the dialogue for a moment. If true judgment is not enough — because it could be a lucky guess, a blind man stumbling down the right road — what else do you need in order to have knowledge?
Audience: I think you need some kind of rationale. In the sidewalk example, you would need to know that it is really concrete, that you know the properties of concrete, and that you are not going to fall through it. But then it seems you already need knowledge to build upon.
That sounds right — some form of investigation, rationale, or justification. That is, in fact, where the dialogue is headed. The final section will argue that knowledge is true judgment plus a logos, translated as account, though it can equally be rendered as justification, explanation, or reason.
Audience: It almost feels experimental — as though the logos is the endpoint, and that the stumbling along the way, the testing of one hypothesis after another, is part of the process.
I like that framing. The whole dialogue is itself an example of at least trying to give an account, and of trying to reach knowledge about the very nature of knowledge. I am fairly confident that something like that is going on — a kind of self-exemplification of the problem at hand. With that in mind, they now go off on a tangent about false judgment.
There are several arguments that would seem to suggest that false judgment is impossible. These are all bad arguments — all sophistical arguments — but the challenge is to explain exactly why they are sophistical and to break through them to understand the real nature of error.
The first apparent problem is that either you know something or you don't — it is a binary state. So what is going on in false judgment? If you know something, you are not going to confuse it with something you don't know, and if you don't know it, you are not going to confuse it with something you do know. A terrible argument, but initially puzzling.
The second argument is framed in terms of being, and here there are shades of Parmenides, who said that there can be no non-being — that non-being is unthinkable and incomprehensible. One might try to describe false judgment as judging something that doesn't exist, as a judgment about non-being, about nothing. The problem is that if your judgment is about nothing, that sounds like not judging at all. Doesn't all judgment have to be about something, and therefore about being, and therefore true? It is worth noting that there is a sequel to the Theaetetus called the Sophist, where Plato takes up the question of non-being more deeply.
The third suggestion is that in false judgment you are taking two things that really exist — two beings — and swapping one for the other. Suppose you are mistaking a cow for a horse: both are real. But the problem is that judgment is, in a way, talking to yourself, telling yourself something — and you never tell yourself "a cow is a horse." Who would think such a thing? Or "justice is injustice" — nobody is ever going to think that. And so we find ourselves caught up in these sophistical arguments.
At 191A, Socrates says that if they find what they are after and become free men, they will turn around and discuss how these confusions happen to others, having secured their own persons against ridicule. But if they cannot find any way of extricating themselves, they will be laid low like seasick passengers and give themselves into the hands of the argument, letting it trample all over them and do what it likes with them. This is an interesting counterpoint to what Theodorus said in the digression — that arguments are our slaves and we can make them do whatever we want. Here Socrates is saying that sometimes the logic of an argument steps on you and enslaves you instead. What might get us out of these problems is yet to be seen.
Let's say that in our souls we have a chunk of wax. When you perceive something — or even when you think something — it can leave a mark in the wax. That is what memory is. Of course, Plato doesn't mean this literally; the only wax in your head is in your ear canal. But we still talk this way: we say that something "made a big impression" on us, or that a person is very impressionable. It does seem that there must be something in our brains that is wax-like — something capable of receiving the stamp of things.
What gets stamped is not the matter of the thing. If you remember what a building looks like, that doesn't mean a bunch of bricks got into your head; what gets in is the form of it. This is precisely why we speak of information: we receive information from things, and that information forms something in our neurons — our wax, whatever we want to call it — and leaves that mark, that impression, within us. It is a useful model.
In the ancient world, there would have been a couple of familiar reference points for this idea. If you look at ancient artworks, you will sometimes see Greeks and Romans working on what looks like a laptop — but it is actually a hinged wax tablet. Each surface was coated with wax; papyrus and ink were expensive, so instead you would use a small stylus to scratch your temporary notes into the wax, then wipe it clean when you wanted a fresh surface. Another common object would be sealing wax for a letter: you would press a signet ring bearing your unique pattern into the wax to show that you were the sender and that the letter had not been opened. These were everyday things.
Audience: So the ancient version of an Etch A Sketch?
Easier to use, though. The model seems fairly plausible so far. There are several features of wax that map neatly onto features of memory. Some people simply don't have much wax — they cannot retain very much. Others have extraordinary amounts; there are people with hypermemories who can recall without effort what they had for breakfast fourteen years ago. Sometimes the wax is too soft, and impressions don't last long. Other times it is very hard, making it difficult for anything to leave a mark — but when something does, it stays for life.
Audience: Do you know whether this wax metaphor had been used before Plato?
I am not enough of a philologist to say with certainty whether anyone before Plato introduced it, but Plato certainly develops it quite far. I also love the passage where he speaks of impurities in the wax and how they prevent complete impressions from forming. Some people have dirty wax, as it were, and they don't remember very well.
How is the wax block going to help us address the question of false judgment? Using this diagram — which I am borrowing from Seth Benedetti, whose translation and commentary on the Theaetetus is often quite intricate but is very straightforward on this point — we can map out the possibilities. This first case could represent a true judgment: you are seeing a triangle, you correctly fit it into the existing slot, and that is a correct judgment. In the second case, there is no judgment, true or false — you simply have a memory and are not perceiving anything to fit into that slot. In the third case, you are seeing a circle but you are not making a mistake; you are not leaping to the conclusion that it is a triangle, which is why there is no arrow.
Socrates works through a long list of situations where false judgment is impossible — this is Theaetetus 192A through C — and the passage is perhaps deliberately abstruse and confusing. Theaetetus very honestly says he has no idea what Socrates is talking about. But the basic point is not hard: when is false judgment actually possible?
One possibility is that you have never seen a circle before and you say, "That's a triangle," and you actually make that judgment — there is your falsehood. Another possibility is that you do know what a circle is and you know what a triangle is, yet you look at a circle and say, "That's a triangle." The object is not unfamiliar, but somehow you place it into the wrong slot. This may seem like a silly mistake, but consider a more realistic case: you have two friends, and you see one of them at a distance and get confused about which one it is, especially if they resemble each other. Socrates introduces one more scenario involving these two friends — call them Mr. Triangle and Mr. Circle — seen at a distance, so that you swap them. He compares it to putting your shoes on the wrong feet.
What do all of these cases have in common? They all involve both perception and memory, and they are all cases of misidentifying what you are currently perceiving. In this sense, it is possible not to know what you know, which sounded impossible according to the first sophistical argument. I know my friend Mr. Circle in the sense that I am familiar with him and have had an impression of him, but I do not know him in the sense of recognizing him correctly — I think someone else is him and he is someone else.
Audience: None of these require shortcomings of the wax, do they? It could just be a difficult perceptual situation.
Yes — you can have all these kinds of misjudgments without any defect in the impression left on the wax. Though if your wax were defective in some way, you would presumably be more liable to this kind of error.
Audience: Is it possible to make a false judgment when there is no impression at all? If you are told that in a room there is a man named Tom and a man named Frank, and you walk in with zero prior impression of either of them, and you address them by the wrong names, that still seems like a false judgment.
That is a good objection. It is a misidentification, but not one of fitting a perception into a previous memory, since you have no previous memory of these people. One could argue, technically, that you do have the memory of being told their names, which might count as a kind of impression — but that is a stretch, and it is an interesting case that had not occurred to me. In any event, the problem Socrates raises next is that we sometimes make false judgments that do not involve perception at all.
Consider the example of mental arithmetic: seven plus five equals eleven. That is perhaps too simple to trip anyone up, but it serves as Socrates' illustration. With more complicated calculations done in your head, you could easily make a mistake — you know the numbers, but you pull out the wrong one. The wax block model does not seem to account for this very well.
Recall that the wax block can take impressions of thoughts and concepts as well as perceptions. So perhaps this is your impression of the number eleven, and this is your impression of the number twelve. How would you ever get them mixed up? There they are — two distinct marks in your wax block, and there is nothing you are misidentifying in perception. How could you ever be mistaken? And yet, often you are.
Our model of memory, then, however plausible and useful it seems, must be inadequate. Error has to be possible not only in matching something you perceive to something you remember, but in the act of recollection itself — in some interior operation of the mind, the psyche, the soul. This is not a matter of misapprehending external reality; it is happening somewhere else entirely.
The psyche, therefore, must have levels. It must have depth. The wax block does not offer much depth — deeper imprints, perhaps, but not genuine levels. Memory must have strata that are difficult to access; one must sometimes struggle to reach in and retrieve the right piece of knowledge. That is what Socrates will attempt to model with his next analogy.
The new model must also be more dynamic, because knowledge can elude you — it can slip away. With that, we have reached the conclusion of this section of the dialogue.
Audience: One thing that's bothering me — and maybe it will come up in the final part — is that Socrates seems to be assuming that truth is a unified thing. I wonder whether he's going to arrive anywhere with that, or whether we're going to have to accept that truth is merely apparent.
I'm sure, being a fan of Socrates, that he would welcome your question. I agree, though, that he hasn't said much about it other than that in order to get truth, you have to get to being. Of course, the meaning of being is itself a rather large question.
One traditional understanding of truth is that it is a correspondence — a correspondence between your judgment and the way things are, the being of things. But what does that mean exactly? A mental event and, say, a building made of bricks are very different sorts of things. How do they correspond? What do they share? Or perhaps it is not your mental state but your statement itself — a sentence or a proposition — that somehow matches the way things are. Again, what does that mean?
Heidegger tries to say that a deeper concept of truth is the revelation, the showing of things. Truth occurs only when showing happens through your assertion or your judgment. He points to the Greek word for truth, aletheia, which literally means unconcealment — non-concealment, non-lethe.
Audience: Is that the word used here — aletheia — the one that's translated?
Yes, aletheia. It is a very common, everyday Greek word, but interestingly, the Greek philosophers themselves never point out that it means non-concealment. There is one passage in Plato's Cratylus — a dialogue entirely about language and etymology — where Socrates discusses the etymology of aletheia, but he is simply having fun there. He invents a playful, phony etymology, claiming it means theia ale, "divine wandering," and toys with Heracliteanism by suggesting that Heraclitus had it right all along and that everything is about flux. Etymologically and philologically, however, it is quite clear that the word means non-concealment, and Heidegger, of course, made a great deal of that.
Do any of you think they are going to answer the question of what knowledge is successfully? I think it is unlikely. We will find out tomorrow.
As a general preview, the dialogue will be working with the idea that knowledge is true judgment plus an account — that is, a true belief together with an explanation. The difficulty, of course, will be determining how one gives an account of an account, and what counts as a genuine account. There will be some very abstract arguments along those lines, and we will see whether any of them work out.