THE ROLE OF RELATIVES IN PLATO'S PARTITION ARGUMENT, REPUBLIC 4, 436  9–439  9 MATTHEW DUNCOMBE O of Socrates' central contentions in Plato's Republic is that the soul has parts. One argument for this claim runs from    to   . Before arguing that the soul has exactly three parts, Socrates argues that it has more than one part. I call this the Partition Argument. Commentators often hold that this argument either under-generates or over-generates parts. On the one hand, if the argument does not involve a genuine conflict, necessary for generating parts, then the argument under-generates. On the other hand, if the key move of the argument can be reiterated indefinitely, the argument over-generates. The Partition Argument contains one of Plato's most important discussions of relatives at   – , although scholars rarely consider the significance of this for the argument. In this paper I show that once we see how Plato's © Matthew Duncombe  Nick Denyer and M. M. McCabe commented on this material in its earliest incarnation as the second chapter of my Ph.D. thesis. Audiences in Groningen, Edinburgh, Exeter, and Reading asked helpful questions on the paper in its second life as a talk. David Sedley, Tamer Nawar, and Mabel Wale gave me extensive written feedback when the paper was born again as continuous prose. The editor of this journal kindly suggested some final improvements. Many thanks to you all.  Socrates calls the elements in the soul 'εἴδη' at   ,   ,   , 'γένη' at   ,   , and 'μέρη' at    and   . These are cited by E. Brown, 'The Unity of the Soul in Plato's Republic' ['Unity'], in R. Barney, T. Brennan, and C. Brittain (eds.), Plato and the Divided Self (Cambridge, ), – at . Socrates' usual way of referring to a particular division is with a neuter noun, which could suggest a 'part' in Greek. There is some debate as to whether they are 'parts' in a literal sense or rather 'aspects'. I will not address this question here, since it is not central to the argument of the paper, but on this see R. C. Cross and A. D. Woozley, Plato's Republic: A Philosophical Commentary [Philosophical] (London, ), ; C. Shields, 'Plato's Divided Soul', in M. McPherran (ed.), Plato's Republic: A Critical Guide (Cambridge, ), –; and C. Shields, 'Simple Souls', in E. Wagner (ed.), Essays on Plato's Psychology (Lanham, Md., ), –.  On a terminological point, relatives are items in the world. Relative terms are the linguistic items which express relativity or refer to relatives. Although Aristotle Created on 12 February 2015 at 21.42 hours page 37  Matthew Duncombe wider view of relatives is involved in the Partition Argument, the argument avoids the two problems. I argue for the following three claims. First: both problems arise if desire and rejection can relate to different objects. If desire and rejection each relate exclusively to the same object, then the Partition Argument avoids both problems. Second: Plato thinks that desires, such as thirst, and rejections, such as dipsophobia, both relate to the same object and only that object. He thinks this because desires and rejections are relatives. Each relative relates exclusively to its correlative. In the case of relatives that are intentional mental states, the state correlates with its intentional object. Third: desire and rejection are opposite relatives. In general, opposite relatives need not relate to the same object. However, when Plato discusses how to qualify relatives in Republic , we discover that in the special case where (a) opposite relatives have sorts and (b) those sorts arise because the relatives are qualified in the same way, then the opposite relatives relate exclusively to the same object. Thirst and dipsophobia exemplify this special case. So thirst and dipsophobia are opposites that relate to the same object. In this way, Plato can avoid the two problems with the Partition Argument. Section  outlines the Partition Argument and the two problems. Section  discusses Plato's wider views of relatives and shows that a relative relates exclusively to its correlative. Section  shows why Plato's Partition Argument avoids the problems, as traditionally conceived. . The Partition Argument The Partition Argument has the following structure: coins the expression 'τὰ πρός τι' for relatives, we will see that Plato characterizes this class of entities and anticipates many of Aristotle's claims about it.  'Dipsophobia' names the sort of rejection that corresponds to the sort of desire called 'thirst'. I use 'rejection' to capture the opposite of 'desire'.  I use this expression as a convenient label for whatever an intentional mental state is directed towards, with two caveats. First, in modern discussions of intentionality the intentional object is often discussed as if it were always a single individual, as in 'Caesar loves Cleopatra', where Cleopatra is the intentional object. But in Plato's case, as will become clear, this object can also be general, as in 'Tantalus desires a drink'. Second, to avoid begging any questions, how an object is thought of is not automatically part of the intentional object. 'Tantalus desires a drink' does not in itself imply that Tantalus thinks of the drink in any particular way. Created on 12 February 2015 at 21.42 hours page 38 Relatives in Plato's Partition Argument  () Principle of opposites. If something is a single item, then it cannot act or be acted upon in opposite ways at the same time, in the same respect, and in relation to the same object (  – ) [Premiss]. () Desire and rejection are opposite ways of acting or being affected (  – ) [Premiss]. () Thirst is the desire for drink (  –  ; cf.   – ) [Premiss]. () Principle of qualification. (a) If a term that is 'of something' is qualified, then it is of a qualified something. (b) If a term that is 'of something' is unqualified, then it is of an unqualified something (  – ) [Premiss]. () Thirst unqualified is the desire for drink unqualified [Modus Ponens on (b) and ()]. () Someone, a, is thirsty and at the same time rejects drink (  –) [Premiss]. () a desires drink unqualified and a rejects drink unqualified [Instantiation of () with ()]. () a acts in opposite ways with respect to drink unqualified [Instantiation of () with ()]. () a is not a single item (  –; cf.   –) [Modus Tollens on () and ()]. Assuming that the soul is the locus of desire and rejection, the argument uses a simple mechanism to show that the soul has parts: the principle of opposites. For any X, the following conditions are individually necessary and jointly sufficient for X to have more than one part. Opposites hold of X: (a) at the same time, (b) in the same  This differs from our principle of non-contradiction: first Plato phrases the principle such that an item cannot have opposite properties, while the PNC (roughly) denies that a proposition and its negation can be true together. The second difference is that Plato's principle concerns opposites, whereas the PNC concerns negations: if X is opposite to Y, then X and Y are exclusive, but need not be exhaustive. But if X is the negation of Y, then X and Y are exclusive and exhaustive. See Brown, 'Unity'.  H. Lorenz, The Brute Within: Appetitive Desire in Plato and Aristotle [Brute] (Oxford, ), –, discusses this premiss in the most detail of any commentator. In my reconstruction, (a) does not play an explicit role in the statement of the argument. However, in sect. , where I give a slightly more rigorous statement of this principle, we will see that (a) is crucial to the validity of the argument.  For other reconstructions see R. F. Stalley, 'Persuasion and the Tripartite Soul in Plato's Republic', Oxford Studies in Ancient Philosophy,  (), – at ; Lorenz, Brute, ; and T. Irwin, Plato's Ethics [Ethics] (Oxford, ), . Created on 12 February 2015 at 21.42 hours page 39  Matthew Duncombe respect, and (c) in relation to the same object. The argument undergenerates parts if one of the conditions (a)–(c) is not met, while if all conditions (a)–(c) are repeatedly met, the argument over-generates parts. I will examine each possibility in Sections . and . respectively. .. Under-generation Let me stipulate that when an agent desires something, X, as good, (i) the agent desires X; (ii) the agent believes that X is good; and (iii) the agent desires X because she believes X is good. Plato's pre-Republic dialogues seem to articulate the 'Socratic' view that whenever an agent desires something, the agent desires it in a qualified way, namely as good. But scholars disagree over Plato's moral psychology in the Republic. Traditionalists think the dialogue rejects Socratic psychology, in favour of the view that some desires are good-indifferent. An agent has a 'good-indifferent' desire for X if (i) is satisfied while (ii) and (iii) are not. Such desires may help explain akrasia. If an agent desires X irrespective of whether the agent thinks X is good or bad, the agent may act to acquire X, even against what she takes to be her interests. Against this, revisionists  Prot.   . For the more general claim that what we desire we believe to be good see e.g. Meno   –  , Gorg.   – , and Prot.   – . The Protagoras also gives the famous formulation of the 'Socratic Paradox': 'Now, no one goes towards the bad, or what he believes to be the bad, willingly. Neither is it in human nature to want to go towards what one believes to be bad instead of the good' (  – ). Although finding a satisfying terminology is difficult, I will use 'Socratic' to refer to the moral psychology of the traditionally conceived preRepublic dialogues. This does not imply that the historical Socrates held this view. I use 'Platonic' to refer to the moral psychology of the Republic, whatever that may be, even though the character called 'Socrates' evinces it. We cannot be sure that Plato, in the Republic or elsewhere, holds the 'Platonic' view in propria persona.  R. Parry, Plato's Craft of Justice (New York, ), –, coins the expression 'good indifferent'. As well as Parry, we might give as 'traditionalists' the following scholars: C. D. C. Reeve, Philosopher-Kings: The Argument of Plato's Republic (Indianapolis, ), –; Irwin, Ethics, ; N. Smith and T. Brickhouse, Plato's Socrates (Oxford, ), –; T. Penner, 'Socrates and the Early Dialogues', in R. Kraut (ed.), The Cambridge Companion to Plato (Cambridge, ), – at ; G. Vlastos, 'Socrates', Proceedings of the British Academy,  (), – at  and ; C. C. W. Taylor, Protagoras (Cambridge, ), . These are cited in G. R. Carone, 'Akrasia in the Republic: Does Plato Change his Mind?' ['Akrasia'], Oxford Studies in Ancient Philosophy,  (), – at –. I would also include T. Penner, 'Thought and Desire in Plato' ['Thought'], in G. Vlastos (ed.), Plato  (Oxford, ), – at –; N. P. White, A Companion to Plato's Republic (Indianapolis, ), –; P. Hoffman, 'Plato on Appetitive Desires in the Republic' ['Appetitive'], Apeiron,  (), –; and Lorenz, Brute, . Created on 12 February 2015 at 21.42 hours page 40 Relatives in Plato's Partition Argument  defend the view that Plato still held, in the Republic, that there are no good-indifferent desires. The debate just sketched centres on this passage from Republic : [T] Thus, [Glaucon] said, each desire itself is only of that which it is of by nature, but the things (sc. desires) of a certain sort are due to that which has been added. So don't let someone, I said, disturb us when we are not paying attention, [saying] that no one desires drink, but good drink, and not food, but good food. For, [someone might say], all people desire good things, so, if thirst is a desire, then it would be for good drink, or of good whatever it is, and similarly with the other desires. (  –  ) Premisses () and () summarize the results of this passage. Socrates denies that thirst is a desire for good drink. Rather, thirst, like each desire, is for its natural object. In the case of thirst, drink is the natural object. So thirst, it appears, is good-indifferent. Traditionalists build their case that the Republic rejects the Socratic view of desire on this passage. While revisionists have independent evidence for their view (such as Rep.  – ; cf.  –;  –  ;  – ), they also try to reclaim [T]. One revisionist strategy for taming [T] distinguishes two readings of 'thirst is the desire for drink'. Carone writes: 'It is perfectly consistent to claim that thirst qua thirst is for drink while every time we wish to drink we desire drink as good.' That is, divide a conceptual reading from a psychological reading of 'thirst is the desire for drink'. Conceptually, thirst is, by definition, desire for drink,  Revisionists include: G. Lesses, 'Weakness, Reason and the Divided Soul in Plato's Republic', History of Philosophy Quarterly,  (), –; G. R. F. Ferrari, 'Akrasia as Neurosis in Plato's Protagoras', Proceedings of the Boston Area Colloquium in Ancient Philosophy,  (), –; Carone, 'Akrasia'; R. Weiss, The Socratic Paradox and its Enemies (Chicago, ), ch. ; J. Moss, 'Pleasure and Illusion in Plato' ['Pleasure'], Philosophy and Phenomenological Research,  (), – at –; and J. Moss, 'Appearances and Calculations: Plato's Division of the Soul' ['Calculations'], Oxford Studies in Ancient Philosophy,  (), – at –; possibly also A. W. Price, Mental Conflict [Conflict] (London, ), –. The 'revisionist' reading actually has some supporters who antedate the 'traditionalist' reading: P. Shorey, The Republic [Republic] (Cambridge, Mass., ), ad loc.; J. Adam, The Republic of Plato (Cambridge, ), ad loc.  My translation, following Shorey, Republic, ad loc.  Socrates repeats the same thought, in similar language, at   – .  Moss, 'Pleasure', , for example, calls the evidence provided by [T] 'at very best inconclusive'.  Carone, 'Akrasia', . Cf. Hoffman, 'Appetitive', ; Moss, 'Calculations', . Created on 12 February 2015 at 21.42 hours page 41  Matthew Duncombe so 'thirst is the desire for drink' is true by meaning alone. The psychological reading, on the other hand, could say that whenever some individual thirsts, they desire a drink. As a matter of contingent fact, thirsty individuals always desire a drink as good. But this is an empirical discovery about human psychology. There is no conflict, revisionists say, between the conceptual definition of thirst as the desire for drink and the contingent fact that every time some agent desires a drink, she desires it as a good. The strategy is then to say that (a) thirst, as defined above, is for drink and (b) in any given case of a thirsty person, Tantalus, say, that person desires drink as a good. But (a) is consistent with (b), while (b) is characteristic of Socratic moral psychology. Thus, [T] is consistent with Socratic moral psychology. [T] is an important step in the Partition Argument. This revisionist reading of [T] threatens the Partition Argument with under-generation. The principle of opposites asserts that conflict within the agent, under certain conditions, requires a division in the soul. Socrates pinpoints the conflict between being thirsty and rejecting some available drink. But once the revisionist distinguishes definitional and psychological readings of 'thirst is the desire for drink', that situation may not meet the conditions for generating a part. 'Thirst is desire for drink', read as a definition, is consistent with the psychological truth that Tantalus, despite his unfortunate situation, rejects this drink. So there may not be a genuine conflict when Tantalus thirsts but rejects some actual drink: by definition Tantalus' thirst is thirst for drink, but Tantalus may still reject some particular drink in front of him. Such conflict is necessary to posit parts in the soul. So the Partition Argument undergenerates. .. Over-generation The under-generation problem parallels an over-generation  Carone, 'Akrasia', . This, I take it, is supposed to be a real, rather than nominal, definition.  In fact, Carone herself argues for something stronger: that in the Republic Socrates explicitly endorses the earlier Socratic position. See Carone, 'Akrasia', –.  R. W. Jordan, Plato's Argument for Forms, Cambridge Philological Society, suppl.  (Cambridge, ), –, and R. Robinson, 'Plato's Separation of Reason from Desire', Phronesis,  (), – at , raise the under-generation objection independently of revisionist considerations, although the problem is still based on the ambiguity of the claim 'thirst is the desire for drink'. Created on 12 February 2015 at 21.42 hours page 42 Relatives in Plato's Partition Argument  problem. Suppose that Tantalus' soul does have at least two parts, including an appetitive part. Suppose further that the appetitive part of Tantalus' soul desires to drink. It desires to drink a hot drink because of the presence of coldness. But it also rejects sweetness. So it desires a hot, non-sweet drink. If a hot, sweet drink is available, it seems that the appetitive part both desires and rejects the drink in question. Therefore, according to the principle of opposites, the appetitive part must have two, non-identical parts, one desiring and the other rejecting the drink in question. We could reiterate these moves again and again, to show that, given Plato's principles, the soul has indefinitely many parts. Some press the over-generation problem independently of wider interpretative concerns. But more often commentators use it to motivate the claim that Plato cannot think that just any kind of conflict results in a partition. Some wish to argue that only a specific sort of conflict generates a part in the soul. For example, some claim that only a conflict between a first-order desire and a second-order aversion to that desire generates a part, e.g. desiring to eat meat, say, but being disgusted by that desire. Others argue that the conflict needs to involve a conception of the good in an appropriate way: for example, conflict over what is good or best for the agent. Denying that just any sort of conflict generates a part is the first step towards making the case that the Partition Argument requires a special sort of conflict. Commentators give the over-generation problem as evidence that Plato cannot have inten-  See Penner, 'Thought', –; J. Annas, An Introduction to Plato's Republic [Introduction] (Oxford, ), ; and Reeve, Philosopher-Kings, –. Cross and Woozley, Philosophical, –, discuss and dismiss a similar objection.  At  – Socrates evinces his view that the addition of warmth to the desire for drink will produce the desire for cold drink.  e.g. Penner, 'Thought', –, and Annas, Introduction, .  Irwin, Ethics, –; Price, Conflict, –. This sort of approach is opposed by C. Bobonich, Plato's Utopia Recast [Utopia] (Oxford, ), –, and Lorenz, Brute, –.  T. Irwin, Plato's Moral Theory: The Early and Middle Dialogues (Oxford, ), ; J. M. Cooper, 'Plato's Theory of Human Motivation' ['Motivation'], History of Philosophy Quarterly,  (), –; Price, Conflict, –; Irwin, Ethics, –, takes a slightly different line from his earlier self.  Irwin, Ethics, ; cf. Bobonich, Utopia, . I will not argue against any reading that claims that some specific sort of conflict, e.g. first-order vs. second-order or some conflict involving the good, is needed for a partition. But I take it that the case for such a reading is undermined once we see that there is a satisfactory reading of conflict as between a first-order desire and a first-order aversion. Created on 12 February 2015 at 21.42 hours page 43  Matthew Duncombe ded just any conflict between desires to generate a part. If he had intended that any sort of conflict could generate a part, there would be too many parts in the soul. I have outlined two problems with the Partition Argument. On the one hand, it may under-generate parts; on the other hand, it may over-generate parts. But both problems emanate from the same fact: desires and rejections, e.g. thirst and dipsophobia, need not relate to the same object. We saw that the under-generation problem arises because a necessary condition is not met when applied to the soul. The revisionist reading suggests that thirst may relate to drink, while the corresponding rejection, dipsophobia, may relate, for example, to drink viewed by the agent as a harm. But here a necessary condition on partition is not met, because the opposites thirst and dipsophobia do not relate to the same object, drink: they relate respectively to drink and drink viewed as a harm. If, however, thirst and dipsophobia related exclusively to drink, the under-generation problem would not arise. Over-generation also arises because thirst and dipsophobia may not relate to one and the same object. In addition to relating to drink, each state may relate to sorts of drink, such as hot drink or sweet drink. If a part of the soul desires and rejects a hot, sweet drink, the sufficient conditions generating a partition within the desiring part are met. If the sufficient conditions on generating a part can be repeatedly met, the Partition Argument over-generates parts. But if drink and dipsophobia related only to drink, rather than also to sorts of drink, reiteration would be impossible. So the Partition Argument would not over-generate parts. In short, Plato could solve both problems if he had some principled reason to think that thirst and dipsophobia relate exclusively to the same object. I argue that he did have such a reason. For Plato  Cooper, 'Motivation', .  These are not the only difficulties with the Partition Argument. Some have pointed out that it is hard to see how the partitioned soul is in any sense a unity (e.g. Brown, 'Unity'; Lorenz, Brute, –; Bobonich, Utopia, –). There are also questions over whether the argument is compatible with the exact parts Socrates wants, i.e. reason, appetite, and spirit (see Cooper, 'Motivation', ). Note that, even if Whiting is correct that Plato holds in the Republic that different individuals can have different numbers of parts in their souls, the overand under-generation problems still loom (J. Whiting, 'Psychic Contingency in the Republic', in Barney et al. (eds.), Plato and the Divided Self , – at ). The problems with the argument apply as long as this is the argument that at least one soul has at least two parts. Created on 12 February 2015 at 21.42 hours page 44 Relatives in Plato's Partition Argument  relatives relate only to their objects, a property I call 'exclusivity'. Since thirst and dipsophobia are relatives, each relates exclusively to its object. However, as far as exclusivity shows, opposite relatives could relate to different objects. Mere exclusivity is not sufficient to ensure that thirst and dipsophobia relate to the same object. So I need to attribute a further claim to Plato: in some cases opposite relatives relate exclusively to the same object. Opposites sometimes obey exclusivity. I argue below that Plato's general view of relatives includes a commitment to exclusivity. It turns out that Plato would also accept that opposites sometimes obey exclusivity because of how he thinks relatives are divided into sorts. Given these assumptions by Plato, we can see that for Plato thirst and dipsophobia relate exclusively to the same object and so neither over-generation nor under-generation would trouble him. . Relatives in Plato In this section I argue that Plato endorsed exclusivity and that thirst and dipsophobia must relate to one and the same object. In Section . I will argue that he held exclusivity. Then, in Section ., I show that desire and rejection are relatives. All relatives exhibit exclusivity; desires and rejections are relatives; so, those mental states exhibit exclusivity. In Section . I examine Plato's discussion of qualified relatives. This investigation shows that thirst and dipsophobia relate exclusively to one and the same object. .. Relatives and exclusivity Plato discusses relatives in a range of passages. He often returns to the example of larger and smaller: the larger relates to the smaller. This correspondence tells us that relatives, for Plato, are not single. Each relative has a correlative partner. Nothing could be larger if it were the only item that existed. If something is larger, then there is something in relation to which it is larger, i.e. the smaller. Nonrelative items, on the other hand, can be single. An item can be a human, for example, even if that item is the only thing there is. Plato's examples reflect the natural thought that relatives come in  e.g. Charm.  – ; Parm.  – ; Rep.  –; Sym.  – ; Theaet. –. Cf. Arist. Cat. a–b. Created on 12 February 2015 at 21.42 hours page 45  Matthew Duncombe pairs: the larger is relative to the smaller and the heavier is relative to the lighter. Relatives relate to a correlative. Since desire relates to the desirable and the desirable relates to desire, the two form a relative–correlative pair. But desire is not just a relative. It is also an intentional mental state. In the special case of relatives that are intentional mental states, the correlative is the intentional object of the state. In the Charmides Socrates discusses the claim that 'knowledge is of nothing but itself and other sorts of knowledge' (  –). First, in language reminiscent of Rep.   – , Socrates says that knowledge 'is of something' (τινὸς εἶναι). He asserts that knowledge and its object are like other relative– correlative pairs, giving the examples of larger–smaller, double– half, more–less, heavier–lighter, and older–younger (  – ). Like these relatives, knowledge relates to its correlative (  – ). But the correlative of knowledge is the intentional object of knowledge, learnings. To confirm this point, Socratesmentions two other intentionalmental states, hearing and sight (  – ). Socrates calls the correlative of hearing 'sound' and the correlative of sight 'colour'. Again, each of these is relative, and it relates to its correlative. If the same thought is in the background of Republic , this suggests that the intentional mental states in the Partition Argument relate to their correlative, which is just the intentional object of that state. The intentional states mentioned are relatives and relate to their intentional objects. But do such states relate only to their object? They do because all relatives relate only to their correlative. I argue that Plato endorses this principle: (Exclusivity) IfX andY are a relative and correlative pair, then X relates only to Y. Thus stated, the exclusivity principle appears too strong to be plausible. Suppose we replace 'X' and 'Y' in the above schema with 'father' and 'son'. Father and son appear to be a relative–correlative pair, but father does not only relate to son. Fathers can also be fathers of daughters. To rule out such counter-examples, Plato, like Aristotle (Cat. b–b), stipulates that when both relative and  There is no evidence that Plato explicitly considered, for example, three-place relations, such as 'x is between y and z'.  This principle cannot be expressed in first-order logic because 'X' and 'Y' range over types, as well as individuals. I use italic capitals to indicate this. Created on 12 February 2015 at 21.42 hours page 46 Relatives in Plato's Partition Argument  correlative are properly specified, exclusivity holds of each pair. In the above example, father relates exclusively to its correlative if, and only if, that correlative is given as 'offspring' i.e. 'son or daughter'. The counter-example gets its force because the following statement is ambiguous: (a) a father is relative to this-and-such. The subject, 'a father', could be understood to indicate fathers as such or some particular father. The former would entail (a′) 'For any father, that father is relative to this-and-such'. The latter gives (a′′) 'For some father, that father is relative to this-and-such'. If we replace 'this-and-such' in (a′) with 'son', the result is that (a′) is false. Whether (a′′) is true under the same substitution depends on who that father is. One way to block such counter-examples would be to specify that we are not thinking about any particular father when we make the statement (a), but rather fathers as such. That would be to disambiguate in favour of (a′). Then it is obvious that the correlative is not son, but offspring, because as fathers, fathers relate to offspring, not just sons or just daughters. In short, when the relative is specified as the relative it is, then it relates only to its correlative, which is also properly specified. Plato has this sort of move available to ensure exclusivity because he introduces terminology to identify how and when a relative and correlative are specified. In the Symposium Socrates mentions the case of brother, another relative, and says: 'Is brother, the very thing that it is [αὐτὸ τοῦθ   ὅπερ ἔστιν], brother of something or not?' (  –). From this context it is clear that Socrates intends the expression 'the very thing that it is' at   – to rule out all improper ways of using 'brother': he means to specify brother as such. Just a few lines above, at   –, Socrates headed off confusion over the proper correlative of love. Socrates is interested in the relative love as such, not in some particular variety of love, such as love of a father or mother. The relative, love as such, always relates exclusively to its correlative. Socrates clarifies by drawing an analogy with the term 'father' and asks Agathon to imagine he had asked what the correlative of 'father itself ' (αὐτὸ τοῦτο πατέρα) is (  ). He receives the answer  This way of thinking about relatives is foreign to treatments of relatives descended from Frege and Russell, who give an account in extensional terms. But some modern work on propositional attitudes would find these ideas familiar. See W. V. O. Quine, 'Quantifiers and Propositional Attitudes', Journal of Philosophy,  (), –. Created on 12 February 2015 at 21.42 hours page 47  Matthew Duncombe 'son or daughter' (ὑέος γε ἢ θυγατρός), which, although a disjunctive expression, picks out an exclusive correlative for father (  ). Father relates to nothing other than a son or a daughter. So the relative, father, under the description 'father', will relate exclusively to its correlative, in this case labelled 'son or daughter'. The 'itself ' (αὐτό) and 'the very thing that it is' (αὐτὸ τοῦθ   ὅπερ ἔστιν, transliterated as auto touth' hoper estin) vocabulary, applied in the context of relatives, specifies that we should look at the relative under a certain description, that is, as such. In this case we should look at father as a father rather than, say, as a man or a brother or even a father of sons (cf. Cat. , a–b). When we look at the father in the right way, father relates exclusively to its proper correlative. What that correlative is will be obvious if we read the relative in the general sense. When properly specified, relative–correlative pairs obey the exclusivity principle. This point can also be seen in our Republic  passage. The tell-tale use of hoper estin crops up at the Partition Argument. At    Socrates uses a different grammatical form of hoper estin to refer to the object of knowledge, the knowable, with the periphrasis 'the thing which knowledge is of' (αὐτοῦ οὗπερ ἐπιστήμη ἐστίν). Socrates argues that we could specify knowledge in a certain way. For example, medicine is the specific sort of knowledge that deals with health. However, taken independently of further specification, knowledge is knowledge of the knowable. Moreover, to anticipate my discussion in Section ., Plato confirms that desire, in so far as it is a relative, relates only to its object. Socrates mentions the exclusive object of desire periphrastically at   – , as 'that thing which he desires' (  –), then as 'whatever thing he wants' (  ). These expressions designate a correlative to which desire exclusively relates. In the Partition Argument desire relates only to its correlative. All this suggests that, in general and in the Partition Argument,  Socrates uses this vocabulary of 'itself ', 'the very thing that it is', in his crucial moves in the Partition Argument (see sect. ., [T]).  For further evidence of this use of ὅπερ ἔστιν see my article 'The Greatest Difficulty at Parmenides  –  and Plato's Relative Terms' ['Greatest'], Oxford Studies in Ancient Philosophy,  (), – at –, which discusses an occurrence at Parm.   . Although controversial, I think that the same idea can be found at Soph.  –. I discuss this in detail in 'Plato's Absolute and Relative Categories at Soph.   ' ['Categories'], Ancient Philosophy,  (), –. A more straightforward example of this use of the ὅπερ ἔστιν terminology is found at Theaet.   . Created on 12 February 2015 at 21.42 hours page 48 Relatives in Plato's Partition Argument  Plato conceives of each relative as having a correlative, to which it relates exclusively. The technical terminology of hoper estin and the concept of exclusivity bound up with it are found across Plato's discussions of relatives and relative terms, including at a crucial point in the Partition Argument. When the relative (and correlative) are properly specified, there will be an exclusive relationship between them. .. Desire and rejection as relatives in Republic  The underand over-generation problems arose because desires and rejections need not relate only to their correlative objects. If desires and rejections were relatives, they would each relate to their proper object because of the exclusivity principle. Then the problems would not arise. I argue below that Plato thinks the mental states in question are relatives, with the attendant formal properties. The evidence suggests that Plato thinks of desire as a relative in the Partition Argument. There is no doubt that relatives are under discussion in   – . Plato's Socrates designates the class as 'a kind such as to be of something' (ὅσα γ   ἐστὶ τοιαῦτα οἷα εἶναί του) in language which adumbrates Aristotle's definition of relatives as 'all the things which are said to be just what they are of other things' (ὅσα αὐτὰ ἅπερ ἐστὶν ἑτέρων εἶναι λέγεται) at Cat. , a. Plato tends to identify relatives as a class using similar expressions elsewhere, such as Sym.   –. Moreover, the examples of relative– correlative pairs at Rep. ,   – , track examples of relatives given elsewhere by Plato and, indeed, Aristotle. Finally, in [T] Socrates raised the topic of desire and claimed that desire is only for its natural object. In the exchange that follows Socrates wards off Glaucon's worry that desire may only be for the good, rather than the natural object of desire. Socrates does this by appealing to  Shorey, Republic, ad loc., and Carone, 'Akrasia', , make this point.  Although I cannot argue for the point here, I think that there are important conceptual similarities between the way Plato treats relatives and the way Aristotle does in Cat. , as well as some key differences. Nothing I say will turn on the relationship between Plato's and Aristotle's views. In this paper I do not use Aristotle's explicit statements as evidence for Plato's views, although I do sometimes draw illustrative comparisons with Cat. .  For larger and smaller seeCharm.   – andCat. , a–b; for double and half see Charm.   – and Cat. , a–; for heavier and lighter see Charm.   –; for desire see Sym.    and Charm.   –; for knowledge see Charm.   –, Cat. , a–b, b–, b ff., and Parm.   – . Created on 12 February 2015 at 21.42 hours page 49  Matthew Duncombe the formal properties of relatives at   – . Such a move would make sense only if desire were a relative. As well as this circumstantial evidence, we have direct evidence from the Partition Argument that sorts of desire are relatives. At   – Socrates says that thirst falls into the class of relatives that he has characterized between    and   . Finally, textual parallels tell in favour of my reading, since desire features as a relative in the Symposium (  ) and Charmides (  –). If desire is a relative, then it has the formal, logically relevant, characteristics of that class, in particular, exclusivity. But is the opposite of desire, rejection, also a relative, with all the relevant characteristics? Plato does not say so in so many words, but the context posits a strict parallelism between opposites such as assent and dissent (  –). Desires are in the former class, and rejection is explicitly put in the latter class (  –). Since desires are relatives, it is reasonable to hold that their opposites are as well. Moreover, a necessary condition given for partition is that opposites must relate to the same object (  – ); desire and rejection are the pair of opposites in question, so must relate to the same object. But to relate to any object, both desire and rejection must be relatives. As relatives, desires and rejections, in particular, relate exclusively to their correlatives. .. (Some) opposites relate to the same object So far I have argued that relatives for Plato relate exclusively to their correlatives and Plato considers desires and rejections to be relatives. However, nothing I have yet said shows that opposite relatives always relate exclusively to one and the same object. To see that Plato's Partition Argument does not face the overand undergeneration problems, I must show that he would hold that a particular pair of opposite relatives, in this case thirst and dipsophobia, each relates exclusively to one and the same object, namely, drink. Opposite relatives sometimes relate to the same object, but sometimes do not. Take knowledge, which is a common example of a relative, for both Plato and Aristotle. Knowledge relates to the knowable (to epistēton). The opposite of knowledge is ignorance  Aristotle points out that relatives have opposites (Cat. , b–).  For Aristotle, see Cat. b. For Plato, cf. Parm.   – ; Theaet.   –; Rep.   – and   .  At least, this is Aristotle's stable terminology. Plato seems to be feeling his way Created on 12 February 2015 at 21.42 hours page 50 Relatives in Plato's Partition Argument  (Cat. b–). Ignorance also relates to the knowable: one sense of 'ignorance' is 'not knowing something which one could know'. So in this case both opposite relatives relate to the same object, the knowable. Unfortunately for my argument, not all pairs of opposite relatives are like this. Large and small do not have one and the same correlative. The correlative of large is the small, while the correlative of small is the large, but large and small cannot be the same, since they are opposites. I need to show that Plato thinks that the specific opposite relatives in question, thirst and dipsophobia, relate only to one and the same object. Plato's discussion of qualified relatives helps me to show this. Plato's Socrates introduces and explains the principle of qualification for relatives at   – . Since the Partition Argument deals with sorts of relatives, including the much-larger and the going-to-be-larger, Socrates says something about how such qualified relatives behave. Socrates introduces the principle of qualification thus: [T] But surely of all the things which are of such a kind as to be of something [ὅσα γ   ἐστὶ τοιαῦτα οἷα εἶναί του], those that are qualified are of something qualified, so it seems to me, while those that are unqualified are only of things unqualified. (  – ) In my reconstruction of the Partition Argument in Section , I glossed [T] as two conditionals. I can now formulate the conditionals more precisely, using X′ to indicate a sort of X: (A) If (X and Y are a relative–correlative pair) then (X′ is a qualified relative iff Y′ is appropriately qualified). (B) If (X and Y are a relative–correlative pair) then (X is an unqualified relative iff Y is unqualified). somewhat and avoids coining τὸ ἐπιστητόν as the object of knowledge.The expression Plato uses to refer to the proper correlative of 'knowledge' varies between dialogues. At Parm.    the partner is ἀλήθεια; at Charm.  – the partner for knowledge is τὰ μαθήματα, as in Rep. . In Aristotle the partner is ἐπιστητόν (Cat. b). For further discussion see Duncombe, 'Categories', –.  Althoughmost of his examples concern qualifying the correlative, Socrates does also maintain that when the relative is qualified in a certain way, so is the correlative. When discussing thirst as a relative at   – , Socrates makes the point that qualifying by addition can also sometimes qualify the correlative. Qualifying thirst with heat leads someone to thirst for cool drink: qualifying thirst with much leads to the desire for much drink. This is why each of (A) and (B) has a biconditional embedded in the consequent. Created on 12 February 2015 at 21.42 hours page 51  Matthew Duncombe Socrates illustrates the principle of qualification with the example of knowledge and its sorts: [T] But what about knowledges [περὶ τὰς ἐπιστήμας]? Isn't it the same way? Knowledge itself is knowledge of learning itself (or whatever one ought to posit knowledge is of). I mean this sort of thing: did not knowledge of making houses come about when it was divided from other knowledges so as to be called house-building? Absolutely. Was this not because it is of a certain kind, which is some different kind from the others? Yes. Therefore, when it came to be of a certain sort, it became itself a certain sort [of knowledge]? And the same is true of the other crafts and knowledges. That's right. (  – ) For now, I focus on the mechanism for qualifying the relative, in this case knowledge. Knowledge itself is the unqualified relative; learning itself is the corresponding unqualified correlative. Here the expression 'itself ' serves to contrast the relative with its sorts, which are qualified somehow or other. The expression could be rendered 'knowledge unqualified'. One sort of knowledge is the (qualified) relative house-building. According to [T], this 'qualification' came about by a specific mechanism. Knowledge came to relate to a sort of learning, making houses. The sort of knowledge, house-building, resulted from this relationship. This is precisely what (A) leads us to expect. Knowledge and learning constitute a relative and correlative pair: when the latter is qualified, as house-making, so too the former is appropriately qualified, as house-building. So much for how to identify sorts of relatives. For his argument,  Plato uses two expressions for the object of knowledge in  , which I take to be equivalent: the first is 'learning' at    and the second is 'whatever we ought to say knowledge is of' (ἐπιστήμη μὲν αὐτὴ μαθήματος αὐτοῦ ἐπιστήμη ἐστὶν ἢ ὅτου δὴ δεῖ θεῖναι τὴν ἐπιστήμην) at   –. Plato uses 'knowledge itself ' to contrast with some given sort of knowledge. Compare this use with the use we find above where I mentioned that Plato uses the expressions 'itself ' (αὐτό) or 'the very thing that it is' (αὐτὸ τοῦθ   ὅπερ ἔστιν) to specify a relative in such a way as to make its correlative exclusive.  The principle of qualification is not true in an unrestricted form. Take master and slave. When we qualify the correlative as a 'good slave', how should we qualify the master? Clearly, not with 'good': a bad or indifferent master might have good slaves. So with what could we qualify the relative? I can think of nothing plausible. So there may be counter-examples to the unrestricted version of the principle, Created on 12 February 2015 at 21.42 hours page 52 Relatives in Plato's Partition Argument  Socrates also needs to establish that the sorts of relatives relate only to their correlatives. This is straightforward. Take a relative and correlative pair, X and Y. Let X′ be a sort of X. By (A), X′ is itself relative. X′ relates to a sort of the correlative Y, namely, Y′. But by the principle of exclusivity, if X′ relates to Y′, then X′ relates exclusively to Y′. For example, knowledge relates to learning. Knowledge ofmaking houses is itself relative, because it relates to learning about house-building. But, by exclusivity, knowledge of makinghouses relates only to house-building. So sorts of relatives relate only to the relevant sorts of correlative. We can specify a relative as qualified or as unqualified. The same applies to the corresponding correlatives. We have just seen how qualified knowledge, house-making, relates to qualified learning, house-building. In one respect house-making is a sort of knowledge, but in another respect house-making is also a relative in its own right. We could call this unqualified house-making. We can infer by (B) that unqualified house-making is relative to unqualified house-building. Indeed, we may wish to contrast unqualified house-making with some sort of house-making. The sort of housemaking that deals with walls is walling and the corresponding sort of house-building is building walls. Walling relates only to building walls; exclusivity applies to relative and correlative pairs whether they are sorts of some other relative–correlative pair or not. Indeed, this point will become crucial below. A key move in diffusing the overand under-generation problems comes when we see that Socrates takes thirst, which is a sort of desire, as unqualified thirst. When so taken, thirst, now unqualified, will relate only to unqualified drink (  –). So far I have argued that sorts of relatives relate only to sorts of although I know of no discussion of them in Plato. For an importantly different view of how relatives are qualified, see Cat. a–.  Plato's idea that there are different ways of specifying a relative, as qualified or as unqualifed, is analogous to Aristotle's thought in Phys. . , a–b, that a cause can be given in different ways. Aristotle invokes the example of the cause of a sculpture. We can specify the cause as 'a sculptor', 'Polyclitus', or indeed 'a man' or 'an animal'. We can pick out the cause in a range of ways. One way of specifying the cause, 'a sculptor', is privileged, because we are trying to explain how a sculpture came about. At Cat. , a–b, Aristotle applies this thinking to relatives. A master of a slave can be specified in various ways: ideally as 'a master', but also as 'a man' or as 'a biped'. Plato's idea here is similar. A relative is only relative to its proper correlative. But what counts as a proper correlative depends on how the relative is specified, either as qualified in some way or as unqualifed. Created on 12 February 2015 at 21.42 hours page 53  Matthew Duncombe correlatives. But to solve the overand under-generation problems, I need to show that sorts of opposite relatives relate exclusively to one and the same correlative. For example, large and small are a relative–correlative pair. But large and small are also opposites. By (A) both large and small have sorts. Call tallness the sort of largeness related to height and shortness the sort of smallness related to height. Now, in general, sorts of opposites are opposite to each other. Pain opposes pleasure, so physical pain and physical pleasure oppose each other. This is true of opposite relatives: tallness and shortness are opposites, in virtue of being sorts of the opposites large and small. Tallness and shortness are also relatives, in virtue of each having a correlative, namely, height. But, because of the principle of exclusivity, both tallness and shortness relate only to height. So tallness and shortness are opposite relatives, but each is relative to the same thing. Opposite relatives can have the same correlative object. To put the above argument in its general form, X and its opposite, un-X, are both relatives. According to (A) both can be divided into sorts by specifying a term they relate to, Y. Sorts of opposites are themselves opposites, so X′ and un-X′ are opposites. The sorts X′ and un-X′ each have the same correlative, Y. X′ and un-X′ relate exclusively to Y, but Y can be, and in this case is, one and the same correlative for both X′ and un-X′. In this case, X′ and un-X′ are opposite relatives but relate to the same thing, Y. The text of the PartitionArgument supports this treatment of opposite relatives. At   –  Socrates discusses opposing drives relevant to the Partition Argument. At   –  he offers an analogy with archery. The archer both pushes and pulls the bow, at the same time. For Socrates' remarks to make sense, both the push and the pull must be relative to the same object, the bow. But this can only be secured with the considerations given above. Pushing is opposite to pulling. I call the sort of pushing relative to a bow 'bowpushing'. Bow-pushing opposes the sort of pulling that relates to  It may seem odd that height, not shortness, is the correlative of tallness. But this is what the principle of qualification dictates: when we identify the sorts of a relative, e.g. large, the sorts are relatives and relate to the sorting concept, in this case height. As I mentioned above, whether we take relatives as qualified or unqualified matters. If we took tall and short as unqualified relatives, rather than as sorts of large and small, presumably tall and short would be a relative–correlative pair.  The action being referred to is obvious to anyone who has seen archery but hard to describe succinctly. When an archer takes aim, she pushes the bow towards Created on 12 February 2015 at 21.42 hours page 54 Relatives in Plato's Partition Argument  the bow, known as 'drawing'. Both bow-pushing and drawing are relatives and so relate only to their object. But in both cases that object is the bow. So there is direct evidence to show that opposite relatives sometimes relate exclusively to the same object in the Partition Argument. We are now in a position to understand how Socrates applies these general considerations of exclusivity and qualification to desire and thirst and, by extension, rejection and dipsophobia, all of which are key to the Partition Argument. Just after his discussion of the principle of qualification, Socrates continues: [T] [i] To return to thirst, then, do you not place it among those things that are such as to be of something and say that it is what it is [τοῦτο ὅπερ ἐστίν] of something? I presume it is thirst . . .? Yes I do, [it is thirst] for drink. [ii] Therefore, thirst of a certain sort is for drink of a certain sort. [iii] But thirst itself is neither of much nor of little nor of good nor her target with one hand and pulls the bowstring towards herself with the other. Both pushing and pulling are done with respect to the bow, not the target. While there is a common term in English for this pulling, namely, 'drawing', there is no common term for the corresponding pushing, so I simply coin 'bow-pushing'.  In discussion,David Sedley pressed the following point about Plato's treatment of qualified opposite relatives. I have defended elsewhere the view that for Plato, like Aristotle, every correlative is also a relative (Duncombe, 'Categories'; Duncombe 'Greatest'; cf. Cat. b–). Just as knowledge relates to the knowable, so the knowable relates to knowledge. I call this reciprocity. Sedley's worry is that exclusivity, reciprocity, and Plato's ideas about opposite relatives are inconsistent. According to Plato, knowledge and ignorance both relate to the knowable. By reciprocity, the knowable relates to knowledge and the knowable relates to ignorance. But, by exclusivity, the knowable can relate to at most one of these. So exclusivity, reciprocity, and Plato's ideas about qualified opposite relatives lead to a contradiction. As far as I can discern, Plato never recognizes this problem. Aristotle, however, rejects Plato's ideas about qualification of relatives (Cat. a–), so may offer a solution. A full discussion of these interesting issues would take us too far from the argument of this paper, but I will briefly note that, in my reconstruction, the Partition Argument does not rely on reciprocity, so, as far as this argument goes, Plato is consistent.  The text here is corrupt. S. R. Slings (ed.), Platonis Respublica (Oxford, ), prints: Τὸ δὲ δὴ δίψος, ἦν δ   ἐγώ, οὐ τούτων θήσεις τῶν †τινὸς εἶναι τοῦτο ὅπερ ἐστίν†; ἔστι δὲ δήπου δίψος (  –). There are two problems with the text as it stands: the first sentence is ungrammatical, and the second sentence is incomplete. My suggestion is that we understand Glaucon's response as having two parts: the ἔγωγε as responding affirmatively to Socrates' first sentence and the πώματος as Glaucon completing the second sentence in the run of the conversation. This seems to reflect a natural enough conversational rhythm, even if not strictly grammatical. That said, the presence of two textual difficulties in as many lines suggests broader difficulties within the text, and so nothing I say hangs on any specific construal of the syntax here. Created on 12 February 2015 at 21.42 hours page 55  Matthew Duncombe of bad, nor, in a word, of any particular sort, but [iv] thirst itself by nature is only of drink itself. (  –) In this passage the principles of exclusivity and qualification work in tandem to make Socrates' argument. In [i] Socrates uses the expression touto hoper estin to suggest that a relative as such relates only to its object. He applies this general thought to the relative thirst. When specified properly, thirst relates only to drink. We might say that thirst as such relates exclusively to drink as such. The principle of exclusivity tells us this about thirst, because thirst is a relative. Next, Socrates invokes the principle of qualification, in [ii] and [iii]. [ii] says that qualified thirst relates to qualified drink, while [iii] says that unqualified thirst relates only to unqualified drink. This rules out that unqualified thirst relates to drink of a certain sort, for example, good drink. Socrates concludes, at [iv], that thirst as such relates only to drink as such, not to thirst qualified somehow. The move to this conclusion relies on both principles. Qualified correlatives are not properly specified correlatives, for the purposes of the principle of exclusivity. So thirst as such relates only to drink as such, not drink qualified in some way. At first, this may seem a little strange. Is thirst not already a sort of desire? If so, how can thirst, a sort of desire, be thirst as such? But we saw above that sorts of relatives can be viewed simply as relatives tout court. Thirst as such is both a sort of desire and relative only to drink. In fact, Socrates applies the hoper estin expression to thirst in order to emphasize that, even though it is a sort of desire, we can still view thirst as such. When we do so, we will see that the principle of exclusivity applies to thirst and that thirst is relative only to drink. I argued in Section . that relatives have an exclusive correlative, and sorts of relatives relate only to an appropriate sort of their correlative. Section . showed that desire and rejection are relatives. Finally, we saw in Section . that opposite relatives can relate to the same object, and indeed must when they are divided into sorts by relating to the same object. We saw that this applies also in the case of thirst. With these resources, we can now see that the Partition Argument, as Plato understood it, neither over-generates nor under-generates parts. Created on 12 February 2015 at 21.42 hours page 56 Relatives in Plato's Partition Argument  . Solving the problems I will first outline my construal of the argument, then show how the argument faces neither problem. I pointed out in Section  that the principle of opposites specifies three individually necessary and jointly sufficient conditions on anything, X, having parts: X bears opposite relations (a) to the same thing, (b) at the same time, and (c) in the same respect. The Partition Argument assumes that the locus of drives is the soul, and applies these conditions to the soul of an individual, Tantalus, in my example. We make the plausible assumption that Tantalus sometimes thirsts for drink and is dipsophobic for drink, at the same time. When construed my way, Tantalus' soul meets condition (a) since, when specified as thirst, Tantalus' thirst relates to drink. Drink is the object of thirst because thirst is a sort of desire, identified as desire for drink. We saw in Sections . and . that sorts of relatives, including desires, are identified by the correlative to which they exclusively relate. In the case of mental states such as desires, those correlatives are the intentional object. For similar reasons, Tantalus' dipsophobia relates to drink. So Tantalus' soul has opposite relations to the same object. Condition (b) is met by stipulation: we assumed that Tantalus thirsts and is dipsophobic at the same time. Since the soul is the locus of thirst and dipsophobia, Tantalus' soul does both. It is also easy to see how condition (c) is met on my reading. For (c) to hold of Tantalus' soul, it must thirst for and reject drink in the same respect. Section . showed that sorts of relatives, such as thirst and dipsophobia, when specified as such, relate to their object specified as such. Tantalus' thirst is for drink as such and Tantalus' dipsophobia is for drink as such. In both cases Tantalus' attitude is towards drink as such. Hence, there is no room for Tantalus, or his soul, to thirst for drink in one respect and reject it in another. All the individually necessary and jointly sufficient conditions on there being more than one part in Tantalus' soul are met. Construed this way, the argument does not face the overand under-generation problems. To save the Partition Argument from under-generation, Socrates would have to ensure that the same object, under the same aspect, is both desired and rejected, at the same time. Desire and rejection are opposite relatives. We saw in Created on 12 February 2015 at 21.42 hours page 57  Matthew Duncombe Section . that opposite relatives are divided into sorts according to their object. Desire for drink is thirst; rejection of drink is dipsophobia. In virtue of being sorts of opposites, thirst and dipsophobia are opposites. But the principle of exclusivity ensures that thirst and dipsophobia each relate only to drink. The fact that the object of thirst as such and dipsophobia as such is drink as such rules out the possibility that it is desired and rejected under different aspects or at different times. But thirst and dipsophobia are opposite attitudes towards the same object. So there is guaranteed to be a genuine violation of the principle of opposites, which is sufficient to generate a part in the soul. My reading also avoids over-generation. If all conflict in the soul generated a part, then conflict within a part may be sufficient for a partition within that part. Specifically, many readers hold that a thirst for drink and the rejection of some particular drink on offer- say, a hot, sweet drink-would suffice to generate a part within the appetitive part. But now it is easy to see that Plato's Socrates is not committed to anything that would lead to unrestrained over-generation of parts. Thirst as such relates to drink as such. Dipsophobia as such relates to drink as such. An agent cannot have thirst and dipsophobia without psychic conflict. But an agent can thirst and reject a warm drink without conflict. Thirst is relative to drink as such, while the rejection is for warm drink. But drink as such and warm drink are not the same object, so there is not a conflict sufficient to generate a part. . Conclusion The aim of this paper was to show that two principal problems raised against the PartitionArgument can be solved, oncewe understand the notion of relatives at play in the argument. The overand under-generation problems threaten because thirst and dipsophobia may relate to different objects. Plato's conception of relatives blocks this possibility. For Plato, a relative relates to, and only to, its proper correlative. I showed that Plato considers the mental states at stake in the Partition Argument-desire, rejection, thirst, and dipsophobia-to be relatives. 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Whiting, J., 'Psychic Contingency in the Republic', in Barney et al. (eds.), Plato and the Divided Self , –. Created on 12 February 2015 at 21.42 hours page 60 OXFORD STUDIES IN ANCIENT PHILOSOPHY EDITOR: BRAD INWOOD VOLUME XLVIII   3 Created on 12 February 2015 at 21.09 hours page iii