 Hi, I'm Peter Adamson and you're listening to the History of Philosophy podcast, brought to you with the support of King's College London and the Leverhulme Trust, online at www.historyofphilosophy.net. Today's episode, Second Thoughts, Plato's Parmenides and the Forms. Back in episode 18, when I talked about Plato's life and writings, I mentioned that one of the more contentious issues regarding the Platonic dialogues is their chronology. Most scholars accept a broad division of the dialogues into three periods, early, middle, and late, with the so-called Socratic dialogues falling into the early period, the great masterpiece that is the Republic dominating the middle period, and more technical works emerging in the late period, including the one I'm going to be talking about in this episode, the Parmenides. But scholars disagree about the exact order of the dialogues, and about more fundamental issues. How much did Plato's philosophical views change during his career? If his views did change, then in what direction, and on what topics? It's no easy matter to answer these questions. Some think that Plato pretty much never changed his mind or developed new ideas, but was rather setting out a systematic body of doctrines throughout his career, revealing them bit by bit or examining them from different angles in different dialogues. This is how Plato's corpus was seen by most ancient Platonists, but I find this implausible, and would be rather disappointed if it were true. I don't claim to know how geniuses like Plato think, but I'm guessing that they reconsider and develop their ideas quite a lot. In any case, the dialogues themselves provide ample evidence that Plato did reconsider his ideas with a critical eye. This was no simple process, where he set out a doctrine in one dialogue, and then rejected it in a later dialogue. Rather, he refined his ideas and subjected himself to the kind of searching criticism Socrates would mete out to his fellow Athenians in the marketplace. There's no better example than the beginning of Plato's Parmenides. In this dialogue, we see an aged Parmenides, yes, that Parmenides, at the height of his powers, visiting Athens in the company of his friend Zeno. How they managed to travel from Elea to Athens in defiance of Zeno's paradoxes of motion is not recorded. I guess they just went halfway, and then the rest of the way. At any rate, when the dialogue's action begins, Zeno has just finished reading from his book containing those paradoxes. His audience includes a youthful Socrates. As I mentioned in an earlier episode, this juxtaposition of an aged Parmenides, a younger Zeno, and a much younger Socrates helps us establish the relative chronology of the three philosophers, even if we shouldn't take too seriously the idea that the three of them actually met in Athens. Socrates talks to Zeno about the purpose of his paradoxical arguments, which is, of course, to defend Parmenides' claim that all things are in fact one, by showing that if things in the world are many, then they are riven by contradiction. For instance, Zeno tries to show that they would be both similar to each other and dissimilar to each other. Socrates says that this isn't particularly surprising. Of course the things around us are similar in some respects and dissimilar in others. What would be really surprising would be if similarity itself were dissimilar, or if dissimilarity itself were similar. Socrates dismisses the idea that things are one and not many, as Parmenides and Zeno want us to believe. Instead, we should admit that they are both one and many, but we should also hold on to the idea that there is oneness itself and manyness itself. As we saw in Plato's Phaedo, these separate absolute forms would exclude their opposites so that oneness itself could never be many, nor could manyness itself ever be one. As I put it in that earlier episode, forms are immune to the compresence of opposites. But a particular object like a man can partake of opposites at the same time. He is, for instance, both one and many, one man with many body parts. Far from being offended at this demolition of his theory, Parmenides is impressed by the young Socrates, and presses him to say more about these absolute entities like oneness itself and similarity itself. Socrates elaborates, and in so doing produces one of the very few clear explanations of the theory of forms in Plato's dialogues. He posits forms because they are immune from the compresence of opposites, like I just said, but also because the one form can explain why many things share in some character. For example, giraffes, elephants, and skyscrapers will all be large by sharing in a form, namely largeness itself. The forms are separate from the things that partake of them, yet they somehow explain the presence of shared characters in the things that participate in them. So the form of largeness somehow explains or causes the giraffes being large, the elephants being large, and so on. As I say, this is an unusually clear account of the forms. Still, it's basically the theory as we know it from works like The Phaedo and The Republic. In fact, Socrates even mentions the example of sticks and stones, which ensures that we think of The Phaedo. Since we tend to think of this as Plato's signature doctrine, what happens next is a bit of a surprise. Plato allows the more experienced Parmenides to pose a series of problems for the theory of forms, which the inexperienced Socrates is unable to solve. Not only is the theory of forms coming in for some rough treatment here, but we're seeing Parmenides do to Socrates exactly what Socrates usually does to other people, refuting him by asking him questions. At the end of this episode, I'll come back to the question of why Plato might do this, but first let's look at the problems, which come thick and fast in just a few pages of text. Parmenides' first series of questions is a kind of warm-up to the main event. He asks Socrates, basically, which things have forms. Socrates is eager to posit forms like similarity itself and oneness itself and also forms for justice, beauty, and goodness. But what about, say, man or fire? Is there a form of man, a form of fire? Socrates isn't too sure about this. So it looks like the jury is still very much out on the form of giraffe, for those of you who are following this series of podcasts, mostly to find out about the metaphysics of giraffes. And Socrates is downright reluctant to admit forms for things like hair and dirt, maybe because they are too degraded to have forms or because they are mere parts or byproducts of other things. Here Parmenides has touched on a fundamental question about the forms, if not exactly a challenge to the theory as a whole. Suppose there are forms. Well, then how do we find out which things have forms? An obvious question that arises here, though it is not mentioned in the Parmenides, is whether man-made things have forms. Is there a form for chairs, for cars, or space shuttles? Well, maybe not for space shuttles, but in the dialogue Cratylus, which we'll be looking at soon, Socrates seems to talk about a form for the kind of shuttle that is used in weaving. And the Republic speaks about a form of bed. So Plato was certainly open to the idea that there could be forms for man-made things. Here though, Socrates is treating even natural things like man and fire as doubtful cases. So presumably man-made artifacts would be still more doubtful. But as I say, this is just a prelude to more trenchant criticisms. Parmenides chastises Socrates for being particularly worried about cases like hair and dirt, suggesting that this is just a sign of youthful embarrassment. Then he throws down his first fundamental challenge to the theory as a whole. Socrates has talked about things sharing in or partaking in the forms. But how should we understand this? Would each large thing have a piece of the large itself, so that the large itself is split up into many pieces, giving us a bunch of larges, which, paradoxically, would each be small compared to the large itself? Or would the large itself be in each large thing as a whole and thus be separate from itself, because the large that is in the giraffe is not in the same place as the large that is in the skyscraper? Socrates makes a nifty suggestion, which is that the form could be present in its participants the way that the same day is present in many places at the same time. Cheating slightly, Parmenides changes the example. Would it be like a sail, spread out over many people? But in that case, only one part of the sail would be over each person, so we're back to the same problem. Socrates is stumped, but his puzzlement is just beginning. Parmenides next raises the most famous objection in this part of the Parmenides, which Aristotle calls the third man argument. Here in Plato, the example is not man, but largeness again. Here's how it goes. Socrates says we should posit a form every time we see many things which share the same character. So, for instance, we posit the form of largeness to explain the largeness of all the large things. But hang on a minute, isn't the form of largeness itself large? If so, there's another, slightly more extensive group of large things, namely the large things that partake in the form plus the form of largeness itself. So we should posit another, second form of largeness to explain the fact that these things, the large items plus the first form of largeness, are all large. And we can keep going, because there's yet another distinct set of large things, consisting of the large items, the first form of largeness, and the second form of largeness. This means we'll need yet another form of largeness, and so on. We will need an infinite number of forms of largeness, not just one, and the same argument will go for any form we choose. This is the most famous criticism Plato poses to his own theory, but it's not immediately clear why it is so damaging. What if Socrates just said, okay, fine with me, there are an infinite number of forms of largeness. It's not like we'll run out of places to put them, given that, large or not, they are immaterial. The problem, I think, is that Socrates has placed so much emphasis on the idea that each form is one. The whole point was to posit one thing, which explains the common character shared by many things, the one largeness which is set over all the other large things. If there turned out to be indefinitely many forms of largeness, then that would be the exact opposite of what Socrates set out to accomplish. Far from being one, the forms of largeness would be at least as many, if not more so, than their participants. So Socrates needs to answer the criticism. How could he do so? Well, I know what you're thinking. It looks like the damage is done because Socrates admits that the form of largeness is itself large. If he just denied this, then he'd be fine. He doesn't need a second form of largeness to explain why both the large things and the first form are large if the first form of largeness isn't large after all. But it is awkward for him to deny that the form of largeness is large. He's made a really big deal about the fact that the form of largeness is not small, whereas its participants are both large and small. It would be rather surprising to find out that, oh, by the way, the form of largeness is not large, either. Worse, he is inclined to think that the things that partake of a form somehow resemble or imitate that form. If the form of largeness isn't large, then in what sense do other large things resemble it? On the other hand, even without Parmenides' criticism, we might have good reasons for rejecting the idea that the form of largeness is large. Forms are, as I just mentioned, immaterial, so how could a form be large? But if Socrates is tempted to deny that the form of largeness is large, he doesn't do so explicitly. Instead, he changes tack and proposes a surprising interpretation of his own theory. What if forms were not separately existing items in their own right, but just thoughts? He doesn't explain how exactly this would solve the regress problem Parmenides has posed, but maybe it's a way for him to do what I just suggested, to deny that the form of largeness is large. The form would just be a thought in my mind, and obviously a thought can't be large, so no infinite series would be generated. Unfortunately for Socrates, Parmenides makes short work of the suggestion, by pointing out that a thought has to be a thought about something. It will be a thought about the single character that is shared by all the things that are, say, large. This single character, not our thought about it, will be the form, largeness itself, and this must be outside our minds. Socrates agrees and quickly gives up his proposal. He really wants to say that forms are, as he puts it, paradigms that exist in nature, while other things resemble them and are likenesses of them. Oh dear, we're back to the same conception of forms which triggered the third man argument, where we say that they are independent of our minds, separate from the things that partake of them, and somehow similar to the things that partake of them. So Socrates has it coming to him, when Parmenides produces another argument to show that we'll wind up with an infinite regress of forms. This new version has a clever and important twist. Parmenides focuses on Socrates' claim that the form will be similar to the things that partake in it. For instance, large things are like the form of largeness. Doesn't this mean that we need to invoke a second form, the form of similarity, to explain the fact that large things are similar to the form of largeness? Well that seems harmless enough. But now a new regress is looming. We're admitting that each form has its own character. For instance, the form of largeness is large, and the form of similarity is similar. But then, if the large things and the form of largeness are all similar to one another, and if the form of similarity is also similar, then all these items, the large things, the form of largeness, and the form of similarity, share in being similar. Of course, we will need a second form of similarity to explain this, and so on. This time, we get an infinite series of forms, but this time the forms are forms of similarity, rather than of largeness. This is a devilishly clever argument and really gets down to brass tacks by focusing on Socrates' failure to explain in any detail how the form is related to the things that partake of it. But if that's the frying pan, here comes the fire. Parmenides next poses what he describes as the greatest difficulty for the theory of forms. In this final objection, he points out that if the forms are separate, then although they might relate to one another, they won't relate to us, or to the things around us. Parmenides' example is that a human master is the master of a human slave, not of the form of slavery. And the form of mastery itself is not master of some particular slave. If it has mastery over anything, it must be mastery over another form, the form of slavery. So we have two completely disconnected realms, the forms and the things that we're supposed to participate in them. The consequences are disastrous, as Parmenides points out. Socrates wanted the forms to be objects of our knowledge, but knowledge is a connection or a relation, just like mastery or slavery. So if nothing in our world can relate to the world of the forms, then we can't have knowledge of the forms. This greatest difficulty ends the battery of objections against the theory of forms. Socrates is unable to fend them off, which might make us think that Plato sees the objections as unbeatable and is giving up on his theory of forms. But think again, because Parmenides immediately tells Socrates that these objections must be overcome. We need somehow to explain how things can share features like largeness. If we don't, it will be impossible even to carry on talking to one another, presumably because we won't be able to say things like, the giraffe and the elephant are both large. On our next trip to the zoo, we will all be reduced to awkward silence. Now of course, the fact that Plato thinks these objections must be answerable doesn't mean he already has figured out the answers. A famous scholar of Plato's dialogues, Gregory Vlastos, called this part of the Parmenides a, record of honest perplexity. But there are, I think, signs that Plato is optimistic that the objections can be defeated, and perhaps even that sufficiently careful readers can manage this by themselves. Parmenides suggests several times that a more experienced defender of the theory than the youthful Socrates could, with difficulty, answer the objections. And there are a few fairly obvious missteps by Socrates, for instance when he allows Parmenides to cheat by substituting the unfavourable example of a sale for the more illuminating example of the day. Notice also how the series of objections seems to be carefully structured. Parmenides starts by asking what sorts of forms exist, and then moves on to progressively more crucial issues. The first and second objections focus on how a form can be one, the third on its real separate existence outside our minds, the fourth and fifth on the question of how the forms relate to their participants. So the objections form an implicit roadmap, laying out the requirements for a successful theory of forms. Each form must be one, it must be independent of our minds, it must be enough unlike its participants that it is separate, but not so unlike them that the forms become another world unconnected to ours. All of this suggests that Plato is not rejecting the theory of forms, but inviting the reader to consider how it might be refined. In other dialogues, which were probably written in this same later period, he suggests refinements in a more explicit way. One of the questions which has been raised in this first part of the Parmenides is how the forms relate to one another, as well as to their participants. Socrates remarks early on that one goal for his theory would be to explain how things like similarity and dissimilarity, motion and rest, manyness and oneness could be interrelated and distinguished. Precisely this task is tackled in another formidable late work of Plato's, the Sophist. It's a difficult enough dialogue that I hesitate to delve into it on my own. Instead, I'm going to call on the help of an expert on the Sophist who just happens to work right here in London. So join me for a conversation with Fiona Lee about Plato's evolving metaphysics and the Sophist next week on The History of Philosophy Without Any Gaps.