 Hi, I'm Peter Adamson and you're listening to the History of Philosophy Podcast, brought to you with the support of the Philosophy Department at King's College London and the LMU in Munich. Online at www.historyoffilosophy.net. Today's episode, One of a Kind, Gilbert of Poitiers on Individuation. Faithful listeners know a lot about me by now. My love of giraffes in classic film, my baldness, my support for Arsenal Football Club. You may also have noticed that I'm rather keen on the history of philosophy. But here's something that I haven't mentioned yet. I'm an identical twin. Unlike my sister, my twin brother is very much existent. In fact, he runs a museum in Manhattan, the Museum of Art and Design on Columbus Circle. Please drop by if you're in the neighborhood. And it doesn't get much more existent than that. Perhaps it's because I grew up as a twin that I've always been fascinated by the philosophical problem of individuation. What makes two things of the same type different from one another? As children, my brother and I were constantly confronted with adults who seemed to have difficulty with this concept. I hated being called the twins, as if the two of us were entirely interchangeable. And I still bear a grudge against a teacher who was going through an attendance list one morning and called out the Adamsons, apparently unaware that one of us might be present without the other. But you don't have to be a twin to be concerned with the problem of individuation. Consider another set of siblings who were considerably more famous, despite their lack of podcasting and museum directing exploits, the Marx Brothers. It was usually quite easy to tell the Marx Brothers apart, except when Groucho and Harper were performing the wonderful mirror scene in Duck Soup. Do yourself a favor and Google it. But what exactly made them four distinct individuals? This is the flip side of the problem of the universals, where the challenge was accounting for the humanity that belongs to Groucho, Harper, Chico, and Zeppo. Now we're asking not how it is that they all belong to the same species, but how it is that they come to be four separate members of that species. We can also pose the question in this way. How, or why, is humanity divided into Groucho, Harper, me, and my brother, the way that the genus Animal is divided into many species, like human, giraffe, and elephant? Ancient and medieval philosophers did pose the question like that, and added that particulars cannot be further divided in the same way. This is why the particular members of a species are called individuals, and why the difficulty of accounting for the whole phenomenon is called the problem of individuation. You might think that giving a solution is easy. All we need to do is find any feature that belongs to Groucho and doesn't belong to Harper. This feature will distinguish Groucho from Harper, and hence individuate him. For instance, Groucho wears a grease paint mustache, and Harper doesn't. This may be a promising first step, but it's no more than that, because we are not just asking why or how Groucho is distinct from Harper. We want to know how it is that Groucho is distinct from all other humans, what makes him the individual that he is and no other. And as even the merest acquaintance with silent film will tell you, there have been more than a few humans apart from Groucho who wore grease paint mustaches. The same applies to other properties that could help us pick Groucho out from the crowd or from his brothers. Groucho was brilliant at wisecracking, but so was W.C. Fields. He smoked a cigar, but so did Fidel Castro. He later hosted a game show on American television, but so did Wink Martindale. Just as with the problem of universals, late ancient and medieval philosophers thought about individuation within the framework of Aristotelian logic. But which instrument from Aristotle's conceptual toolkit can unlock this particular difficulty? We can immediately rule out the genus and species as candidates for individuating factors. It obviously is not by being an animal or a human that Groucho becomes distinct from all other things, because there are plenty of other animals and humans. For that matter, suppose Groucho were in fact the only existing human, like Adam just after having been created and before a bit of gentle ribbing from God yielded Eve, or perhaps as the only survivor of a disease that strikes down everyone in its path apart from wisecracking game show hosts who smoke cigars and wear grease paint. If Groucho were the only human in existence, then humanity might seem sufficient to individuate him. But even then there would be problems. We really want Groucho to be individuated, not just from all the other things that exist presently, but from all the other things that ever have or will exist. So even if he were the first human, like Adam, or the last one, like the sole survivor of an apocalypse, we would need to say more to explain what makes him unique. In fact, we might even want to guarantee that he is distinct even from other possible humans, like my non-existent sister. This line of thought may push us in the direction of solutions suggested, though not fully worked out, by Porphyry and Boethius. These were the two ancient authors who exerted the most influence on medieval discussions of the problem. Both of them hinted at what we might call an accidentalist theory of individuation. By this I mean the idea that the accidental features of a thing make it the individual that it is. The idea of an accident is standard Aristotelian fare. It just means any feature that belongs to a thing, but not in virtue of the thing's species membership, so that it can survive as the kind of thing it is, even if the feature is lost. For example, Groucho's cigar smoking is accidental to him because he remains a human even when he's not smoking a cigar and even if he quits smoking cigars entirely. By contrast, his being alive is essential, not accidental, since he can no longer exist as a human without being alive. Now we've already seen that an accident like cigar smoking is not up to the job of individuating, since other humans also smoke cigars. But what if we took all the accidental features together? There may be other cigar smokers and other game show hosts, but there aren't likely to be any other cigar smoking game show hosts who are named Marx, wear round glasses, and get mentioned posthumously in philosophy podcasts. Indeed, it seems quite plausible to think that no individual possibly could share all the features of another individual. This is what Porphyry must have been thinking when he remarked, "...things are called individuals because each of them consists of characteristics, the collection of which can never be the same for anything else." Boethius knew this passage well. He commented on Porphyry's introductory illogical work twice, and sometimes spoke as if he agreed with the idea. On the other hand, it may seem superfluous to appeal to all the properties of something if we could just point to one property that nothing else shares or could share. Boethius made a couple of suggestions in this direction too. What if we just referred to the place occupied by something at a given time? That would pick out Groucho very nicely, since nothing else can be exactly where Groucho is when he is there. Alternatively, and rather more mysteriously, Boethius alludes to a special kind of property which belongs to only one person. Using the example of Plato, he says this property would be called platonity. It would be a quality that relates to Plato the way that humanity relates to human. This quality, he says, belongs only to one man and not just to any man, but only to Plato. The idea does have its appeal, not least because, applied to our favorite example, it would give the world the new and delightful word grouchosity. Also, it is clear that, to the extent that we can make sense of a property like this, the property of being Groucho or Plato, it is a property that can be possessed by only one thing. But this will need to be filled in with a lot more detail if it is to provide a truly illuminating account of individuation. Step forward, Gilbert of Poitiers. Distinguished from most of his peers, if not actually individuated, by his unusually sharp intellect and skill in dialectic, Gilbert was a student of Bernard of Chartres and held the office of Chancellor at Chartres in the 1130s, in addition to teaching in Paris. So, Gilbert is yet another representative of the group we have been with some trepidation calling the School of Chartres. His solution to the problem of individuation departs from the accidentalist strategy that had been sketched in Porphyry and Boethius and then adopted by many medieval Rauptu and during the time of Gilbert, including Thierry of Chartres, another student of Bernard, and Thierry's own student, Clarenbold of Arras. Despite the popularity of the accidentalist theory in the early medieval period, and the weight of authority that supported it, Gilbert had good reasons to be skeptical. Just to restate the basic idea, the accidentalist realizes that nothing can be individuated by essential features, since these are shared by all other members of the same species. Groucho is rational, but so are Harpo, my brother, and every other human that ever has or will exist. Instead, we should look to accidental features. While Groucho does have accidents also found in other humans, it could never happen that some other human has all the same accidents. Alternatively, we can point to an accident of Groucho's that nothing else could have, such as his place. Sounds good, right? So what's the problem? Actually, there are several. One might not bother us so much today, but would be seen as deeply troubling in a medieval context. Incorporeal things like God and angels have no place. Indeed, God has no accidents at all. Yet, incorporeal things can be individuals. So the accidentalist account is at best incomplete. We'll have to come up with a separate way to individuate immaterial beings. Another difficulty is that accidents are usually held only temporarily. Indeed, we said that accidental features are precisely the features that a thing can lose, while surviving as the thing it is. How can Groucho be the individual that he is, because of his place, if he can move around? Or how can he be individuated by a whole set of features that include cigar smoking and wisecracking, when he can give up cigars and imitate Harpo's vow of silence? If you think about this, or for that matter if you read Aristotle, you begin to suspect that the accidentalist strategy gets things backwards. Substances like humans, giraffes, trees, and rocks do not depend on their accidents in order to be the substances that they are. To the contrary, Groucho's accident of cigar smoking can only exist thanks to Groucho, because this accident is, as Aristotelians would say, predicated of him. This is just as true of place as it is true of any other accident. For Aristotle and his followers, something's place is, strictly speaking, the boundary of whatever is containing it. For instance, the inner boundary of the air in contact with me right now. If place is determined by the thing placed inside it, how can place do the job of individuating that thing? The problem here is that Groucho's place is defined, indeed individuated, with reference to Groucho, not the other way around. The same applies to other accidents. As Boethius pointed out in his commentaries, Aristotelian logic recognizes not just individual substances like Groucho, but also individual accidents, like the cigar smoking that belongs to him and no one else. It seems that Groucho's cigar smoking is individual because it belongs to him, and that Groucho's place is defined as a limit that surrounds his body. But in that case, the accidentalist story is circular. Groucho is supposedly individuated by his accidents, but his accidents only get to be individual because they belong to him and no one else. At the root of all these difficulties is a fundamental confusion. The accidentalist account is plausible because we do in fact use accidents to tell things apart. We really do tell Groucho from Harpo by noticing that he is, for example, the one with the cigar, and not the one with the blonde wig. But that doesn't mean that accidents really account for the distinctness between things. How could they, if accidents depend on those very things? This would be like saying that the Marx Brothers movies are funny because people laugh at them. It's true that these two things go together, funny movies do provoke laughter, and we can tell that a movie is funny from the fact that people laugh at it. But it's because the movies are funny that people laugh, not the other way around. In the same way, it may be true that we only find particular accidents and unique collections of accidents in individual substances. This is why we can use accidents to tell substances apart, but that has to do with epistemology, not with metaphysics. In other words, accidents show us that things are individual, but they don't explain why things are individual. Gilbert of Poitiers' novel approach to the issue is going to avoid all these problems. How does he manage it? Well, he's a scholastic philosopher, so of course he proceeds by making some careful distinctions. These are often expressed with innovative technical terminology, which does not necessarily make his views easier to follow. He contrasts what something is, id quod est, with that by which it is what it is, id quo est. Groucho is a human, but is what he is through humanity. The same distinction can be made for accidental features. A cigar smoker is what he is by virtue of cigar smoking. Effectively, this just boils down to the distinction between a thing and the features that characterize it. Next, Gilbert says that only a substance and not its characterizing features can be individual. Groucho is an individual, but his humanity, his cigar smoking, and his wisecracking are not. Instead, they are what Gilbert calls dividuals. By this he means that these features can be found elsewhere too. Cigar smoking is divided among Groucho, Fidel Castro, and all the other cigar smokers. Now here comes the clever part. As Boethius taught us, Groucho's cigar smoking is not to be confused with Fidel Castro's. Nor do Groucho and Harpo have the same humanity. Rather, humanity appears twice in them, and four times if you add Chico and Zeppo too. In each of the Marx brothers, in each of the Adamson brothers, in every human, there is a humanity which belongs only to that individual human, while also being similar, or conforming, to other instances of humanity. It is the fact that humanity can be exemplified over and over like this that leads Gilbert to deny that one single instance of humanity can be called an individual. An individual is, as we would expect, something non-repeatable. Nonetheless, the humanity in Groucho is singular, as Gilbert puts it, because it is his humanity and no one else's. These points put Gilbert in a position to make sense of Boethius' suggestion about grouchosity. Grouchosity will be the entire collection, or as Gilbert says, the total form, of Groucho's features. Together, the singular features coalesce, or cohere, into an individual. Though each member of the total form is a divigial, in that a similar property may be found elsewhere, you are never going to find all the properties exemplified anywhere else. While this may sound reminiscent of the accidentalist view, it is really very different. Gilbert actually treats the essential and accidental features of a thing as being on a par, at least as far as individuation goes. All of them are possessed as singular features and serve as parts of the total form that guarantees individuality. Also, unlike his predecessors and contemporaries, Gilbert does not confuse the question of what makes something individual with the question of how we know something is individual. He sees clearly that accidents merely show us that one individual is distinct from another without making it be distinct. We can also see how well he grasps this point from the fact that he includes not only the present features of a thing in the total form, but also all the things past and future properties. Obviously, we currently have no access to future properties, so they can play no practical role in helping us distinguish one individual from another. Imagine how useless it would have been if, when people couldn't tell me and my brother apart as children, my mother had said, oh well the one on the left is the one who will be a philosopher and the one on the right is the future museum director. Metaphysically though, future properties are important, because they enter into the totality of singular characteristics which collectively guarantee the thing's individuality. This also solves the problem about things changing over time. According to Gilbert, it is the total form that individuates, and this includes all the properties the thing has over its whole existence. As an added bonus, Gilbert has a nice story to tell about that other, more celebrated difficulty, the problem of universals. We arrive at a universal by noticing the similarity between singular characteristics, for instance the four instances of humanity in the four Marx Brothers. But, Gilbert insists, everything that really exists is singular. Universal humanity, freed from connection to any individual human, is only a conceptual construct. Yet it does guide our thought in a useful and accurate way, since all humans do really each possess their own singular humanity. On this score, Gilbert is fairly close to Abelard's nominalism. We can also guess what he might say to the obvious complaint that he is just helping himself to the idea that Groucho's humanity, cigar smoking and so on, are singular. Is he assuming too much here? After all, what we wanted to do is explain, in the first place, how it comes to be that there are single things in the world, and not just universal things. To this, Gilbert can reply that there are no universal things, nothing can exist without being singular. If Groucho is a cigar-smoking human, then his cigar-smoking and his humanity must be real, so they must be singular. Gilbert of Poitiers' subtle account of individuality is quite an achievement, and one that shows how much good philosophy could be done within the apparently unpromising context of commentary upon centuries-old logical works. One should not be misled by that context though. Gilbert's aim was not just to explain authoritative works of logic, or even to devise a powerful and original account of individuality. The whole time, he had his eye on related theological issues. For instance, his theory enables him to say very clearly what it means for God to be simple. Whereas all other individuals have total forms, made up of many characterizing features, God is what He is through a single, simple form called divinity. This is one of the doctrines for which Gilbert, like Peter Abelard, was attacked by Bernard of Clairvaux and his allies. When he was put on trial in 1147, with the Pope himself being asked to judge on the question of Gilbert's heresy, the very first accusation was that he taught that God is distinct from the form or nature of divinity. Gilbert came out of his ordeal better than Abelard did, since he was cleared of the charges after a confession of faith was drawn up, which was acceptable both to him and to his critics. He later had a small measure of revenge upon Bernard of Clairvaux. When the great man held out an olive branch by suggesting a meeting to read through some theological texts together, Gilbert suggested that Bernard would be better served by learning some beginner's level material from the school curriculum. With Gilbert of Poitiers, we've almost finished with the scholars connected to the so-called School of Chartres. But there's one important member of this group who remains to be considered, John of Salisbury. He briefly studied with Gilbert in Paris and is among our most important sources of information on philosophy in the 12th century. Not only that, but John was one of the first medieval thinkers to write a treatise dedicated specifically to political philosophy. To understand it, we'll have to look at the historical political context, and especially the famous investiture controversy, which pitted secular authority against the church. That will be our topic two weeks from now. But first we'll be investing a little more time in metaphysics. We've just seen that individuals were often understood as parts or divisions of universals. But what about the parts of the individuals themselves? Things like my brother's hands, or his hair, if that is, he had any hair. Like I said, we're identical. Medieval thinkers had a lot to say about this too, as we'll be discovering next time in an interview with Andrew Arlig, an expert on medieval myriology, the study of parts and wholes. And the best part is, you only have to wait a mere seven days, until the next episode of The History of Philosophy, without any gaps.