1 The Chestnut
My topic is that most chestnut-y of old chestnuts, Socrates’ distinction between knowledge and belief in the argument directed at the sight-lovers at the end of Republic 5 (476c7–480a13).Footnote 1 The chestnut itself might be stated like this:
In 477c–d, Socrates states identity conditions for powers (dunameis): the conditions under which two powers are the same power and the conditions under which two powers are distinct powers.
Shall we say that powersFootnote 2 are some kind of being, precisely the things by means of which both we – and whatever else may be capable – are capable of the things we are capable of. I mean, for example, that sight and hearing are among the powers, if you understand the type I wish to speak of.
I do understand, he said.
Then hear what seems to me the case about them. In the case of a power, I see neither any colour nor shape nor any of the other sorts of features such as many other things do have, paying attention to which I distinguish for myself regarding some things one group from another. In the case of a power I look only to that over which it is and what it effects; and I call each of them a power in this way: what has been put in position over the same thing and effected the same thing I call the same [power]; whereas what [has been put in position] over a different thing and effected a different thing [I call] another [power]. What about you? What do you do?
This.Footnote 3
At worst, Socrates here commits the fallacy of inferring from the claim that powers are the same when they both do and are set over the same things that two powers will differ only if they both do different things and are set over different things. At best, Socrates apparently arbitrarily stipulates identity and distinctness conditions for powers from which it follows that knowledge and belief cannot share the same objects.Footnote 4 But this seems puzzling. First, intuitively, it is possible for one person to have knowledge of the very same thing that another person believes; indeed, in modern epistemological discussions it is assumed that knowledge entails belief so that whatever a person knows that same person will also believe. Second, if Socrates’ position entails that a knower of the Form of Justice cannot bring that knowledge to bear in knowing, of some action, that it (the action in question) is just, it is hard to see how the philosophers’ hard won knowledge will bring them much success in ruling. But the argument in which this chestnut appears forms part of a sequence of arguments whose intended goal is to support the claim that philosophers should rule, in part by pointing to the fact that philosophers have knowledge.
In addressing this chestnut, I want to highlight and reject one central assumption on which such a reading of it depends. This is the assumption that when Socrates identifies a power as being set over some type of object, the relation of being set over entails that one can exercise that power only in relation to the relevant object type. Evidently, such an assumption is necessary to this reading of the chestnut. Absent this assumption, it would not follow from knowledge and belief being different powers and set over different objects that knowledge and belief could not also be exercised in relation to the same objects, so that the same things could be both known and believed.Footnote 5
I shall defend an alternative understanding of the ‘being set over’ relation, according to which a power being set over some type of object does not entail that the power can be exercised only in relation to that type of object. Rather, the relation of being set over indicates the kind of object to which a power is specially related, for which it is tasked, as it were.Footnote 6 It does not follow from this that the power cannot be exercised in relation to other types of object. At most it follows only that, if it is exercised in relation to other types of object, its special object has some role to play in the exercise. Even this does not follow exactly, though I will argue that something like it is part of the view.
The kind of position I have in mind can be illustrated using one of Socrates’ own examples: the power of seeing. Colour is the obvious candidate special object of the power that is seeing. But this does not mean that colours are the only things I can see: I can see people, places and things. Colours, however, do play a role in any exercise of seeing.Footnote 7 The fact that they do so might be said to ‘colour’ my seeing (pardon the pun): it affects what my seeing of other things is like – the aspect of things I have access to in seeing them, the character of that access, and so on. One might compare the Aristotelian picture according to which colours are the special objects of seeing, with no implication that colours are the only things I can see. (Indeed, the availability of the comparison may be indirectly supportive of my thesis.)
However, if the seeing example supports rejection of the restriction of the exercise of a power to its special domain, in conjunction with Socrates’ second example, hearing, it raises the spectre of a different problem. While there are objects that I can both see and hear, the objects for which seeing and hearing seem specially tasked, colours and sounds, exclude one another in the sense that, synaesthesia aside, one cannot see sounds or hear colours. If the objects for which the powers of knowledge and belief are tasked relate to each other in this way, the chestnut will still fruit. This exclusivity of special object, however, I take to be an inessential feature of Socrates’ choice of examples, as the background to the passage will show. The situation is (non-accidentally) comparable to the way in which, in Republic Book 1, Socrates illustrates his notion of the ergon (the work or function) of something (that which something does only or best with that thing, 352e3–4) by pointing to seeing, the ergon of eyes, an activity that only eyes can do.
2 Evidence for My View
The resolution of the chestnut is itself part of the evidence I would offer for my view. But this evidence would not be complete without a fuller defence of the chestnut’s needing to be resolved. Some think the distinction of objects for knowledge and for belief in such a way that nothing can be both known and believed is not a bug, but a feature of Plato’s epistemology.Footnote 8 Nor could the evidence provided by resolution of the chestnut be complete without a full statement of the corresponding reading of the argument in which the chestnut appears, defended against alternatives. That is a task beyond the scope of the present chapter. For now, my evidence will be finer-grained: attention to the language in which Socrates expresses his criteria for the individuation of powers, especially in light of a passage with comparable language in Republic Book 1.
Others have noted that Socrates’ epistemology centrally involves the view that knowledge is a dunamis or power, and, more generally, Socrates’ notion of a power has been a focus of study.Footnote 9 The material from Republic 1 that I shall consider has been included in such study. But discussions of this feature of Socrates’ epistemology and of his conception of power have not been brought to bear on the talk of knowledge and belief as powers in Republic 5 and the literatures on each have not typically been brought into conversation with one another.Footnote 10 There is, therefore, independent value in connecting the material on which I shall draw in Book 1 with the discussion of powers in Book 5.
2.1 Epi with Dative
Start with Socrates’ language, in 477d1–5, when he states his identity conditions for powers:
δυνάμεως δ’ εἰς ἐκεῖνο μόνον βλέπω ἐφ’ ᾧ τε ἔστι καὶ ὃ ἀπεργάζεται, καὶ ταύτῃ ἑκάστην αὐτῶν δύναμιν ἐκάλεσα, καὶ τὴν μὲν ἐπὶ τῷ αὐτῷ τεταγμένην καὶ τὸ αὐτὸ ἀπεργαζομένην τὴν αὐτὴν καλῶ, τὴν δὲ ἐπὶ ἑτέρῳ καὶ ἕτερον ἀπεργαζομένην ἄλλην.
In the case of a power I look only to that over which (epi) it is and what it effects (apergazetai); and I call each of them a power in this way: what has been put in position over the same thing and effected the same thing I call the same [power]; whereas what [has been put in position] over a different thing and effected a different thing [I call] another [power].Footnote 11
What should be understood by Socrates’ use here and elsewhere in the passage of the preposition ‘epi’ with dative? He uses it in combination with the verb ‘to be’ (einai), with ‘pephuken’ (to be of a nature to), but also, and most illuminatingly, with the verb ‘tassō’ (to marshal or put in position) (for example, at 477b8 and 477d4). This latter is a military verb with normative connotations.Footnote 12 It suggests that powers stand in relation to (epi) things to which they have been assigned, stationed or positioned, which are, as it were, their post.Footnote 13 Especially in the context of this military verb, ‘epi’ with dative seems most appropriately understood in context as indicating a domain of normative assignment for powers.Footnote 14
Domains of normative assignment are not obviously distinguished in any of the ways that spell trouble for Socrates. The military context provides examples of domains of normative assignment that cooperate on shared tasks, domains that overlap and that may stand in various subordination relations.
Consider first how a squadron of soldiers may cooperate in an assault on a military target in such a way that specialized soldiers fulfil specialized tasks towards the goal: one sets charges, another stands lookout, for example. In this example, there are particular tasks for which particular specialized soldiers are tasked and which, in the normal run of things, only those specialized soldiers will fulfil. But there will be other tasks, such as firing at the enemy or defending each other, for which all are tasked; and there is one task, the assault as a whole, which all share together.
Consider a second military example: In the US military, a squadron, made up of individual soldiers, is led by a sergeant; and a platoon, made up of a number of squadrons, is led by a lieutenant. The domains of command of lieutenant and sergeant overlap; the command of the sergeant is subordinated to that of the lieutenant; and the soldiers in the domain are not exclusively responsive to sergeant or lieutenant. This is an example in which the overlapping tasks are both similar and subordinated – command; think of this as a vertical relation between tasks. As we saw in the first example, a domain may also form the arena of operation of tasks that are not similar; think of this as a horizontal relation between tasks, as obtains in respect of a single company of soldiers between the tasks of quartermaster and commander, for example.
Consider a third military example: A domain of normative assignment need not exhaust the possible sphere of operation of the person or power whose task is specially related to the domain. At least in certain circumstances, the sergeant of one squadron may command an individual soldier outside of his or her squadron and being in command of certain soldiers presumably does not exhaust the military activity of a sergeant.
It may be helpful at this point to distinguish different ways in which domains – of any sort – may be distinct from one another and to fix some terminology to use for these kinds of distinction. ‘Distinct’ itself may be used to indicate either that two domains are non-identical or that two domains are, not only not identical, but also disjoint, which is to say that the two domains do not overlap with one another. When necessary, I shall talk of things that are distinct and non-overlapping, as distinct from things that are distinct and overlapping. My military examples illustrate the general point that items in some domain of normative assignment are not, simply in virtue of this fact, automatically distinct in either of these two specific ways.
Contrast these two ways in which one domain of normative assignment for some power might be distinct from another from a different relation, that of being exclusive. Two domains are exclusive if, for two distinct powers, p1 and p2, the members of the domain of power p1 exclude the operation of the power p2 and the members of the domain of power p2 exclude the operation of the power p1. With respect to the powers of seeing and hearing, colours and sounds are arguably exclusive in this way. My third military example illustrates the point that two domains may be distinct and non-overlapping but nevertheless not exclusive. I shall argue that Socrates’ conception of the powers, knowledge and belief, allows that their respective domains are non-exclusive. This is consistent with (though does not require) the domains of these powers being distinct and non-overlapping.
Note that, while the military examples show that domains of normative assignment need not be distinct or exclusive, they also suggest some important sense in which the relation between the element to which a task is assigned and the domain of its assignment is unique: organized systems such as the military avoid redundancy by not assigning the same task in relation to the objects of a domain twice over.Footnote 15
My military examples are not in themselves designed to establish any specific positive constraints on how we should understand Socrates’ picture of the relation between a power and its domain. My use of the military analogy is designed to make the negative point that domains of normative assignment are not in and of themselves exclusive in the way required for the reading of the chestnut according to which an exercise of the power that is knowledge or belief can be exercised only in relation to items in the domain over which it is set as a power. I shall shortly turn to Republic Book 1 for additional support for understanding the domain of a power as one of normative assignment. This is also the context on which I shall draw for a positive account of Socrates’ constraints on the relation between powers and their domains of normative assignment. First, however, I want to pick up the remaining part of Socrates’ characterization of powers in the Book 5 passage.
2.2 What Powers Effect (apergazetai)
Socrates distinguishes powers not only by giving them distinct domains of normative assignment, but also by pointing to a difference in what they effect (apergazetai). What is the effect of a power?
Socrates is not explicit on this point, but there is reason to think that the effects of the powers, knowledge and belief, are simply the activities of knowing (more precisely, knowing what is, that/how it is) and believing.Footnote 16 There are two main pieces of evidence for this. First, at 477d8–e4, when Socrates and Glaucon formally agree that each of knowledge and belief should be identified as a power, Glaucon identifies belief as the power ‘by which we are capable of believing’ (e3). This suggests that the effect of the power belief just is the activity of believing. The second piece of evidence comes from the structure of Socrates’ argument at 478a4–13. Socrates and Glaucon have just recalled their agreement that knowledge and belief are different powers. In what follows, Socrates clearly means to apply his criteria for distinguishing different powers to show that, being different powers, knowledge and belief are both over different things and have different effects.
Is, then, each of them [sc. knowledge and belief], being capable of something different, naturally over something different?
Necessarily.
But knowledge is presumably over what is, to know respecting what is that/how it is?
Yes.
Whereas belief, we say, believes?
Yes.
Does it [believe] the very same thing that knowledge knows? And will the same thing be both knowable and believable? Or is that impossible?
Impossible, he said, on the basis of what has been agreed.
It is clear where in this passage Socrates applies that part of his criterion for distinctness of powers that sets different powers over different things. Knowledge is ‘over what is’. We are not yet told what belief is set over, but we do draw the negative conclusion that it is impossible that it be set over the same thing as knowledge is. Where then does he draw the conclusion regarding their different effects? The answer must be that he does so when he characterizes knowledge as set over what is ‘to know … that/how it is’ and characterizes belief as ‘believing’. So understood, his argument has a nice chiastic structure: knowledge is set over A and accomplishes B; belief accomplishes B*, which leaves us with the substantive claim to be made by the next stage of the argument, to identify more precisely A*, the distinct thing that belief is set over to effect believing. This turns out to be what both is and is not (see, e.g., 478e2).
I have argued that the effects of the powers, knowledge and belief, are the activities of knowing and believing. However, this does not mean that, for any power Φ, its effect is the activity of Φ-ing. ‘Apergazomai’ – the verb that Socrates uses in his statement of this part of his identity conditions – is often found in Plato with its cognate accusative: ‘to ergon apergazomai’ (to effect its work or function). Two examples are found in the so-called ‘ergon argument’ at the end of Republic I (353b14–c1; 353c9–10). I shall shortly argue that the framework of this earlier argument provides important background to the discussion of powers in Book 5. The use of the verb with cognate accusative suggests that the most general way in which to identify the effect of a power is as its ergon. For some powers, the ergon of a power Φ is the activity of Φ-ing; but for others, the ergon is something resulting from this activity. This kind of view is familiar, of course, from Book 1 of Aristotle’s Nicomachean Ethics.
In EN 1, Aristotle has at least half an eye on the ergon argument of Republic 1. So should we. I have already provided some evidence that Socrates’ use in Book 5 of ‘epi’ with dative indicates a domain of normative assignment for powers. Socrates’ verb for a power’s production of its effect, apergazomai, can be read flatly as indicating simply that something is caused or produced. But this verb too can carry normative connotations of completing or bringing to perfection some ergon. The ergon argument of Republic 1 occurs at the end of a lengthy passage in which the cluster of terms that Socrates uses in formulating his identity conditions for powers makes its first appearance. Consideration of this passage provides significant support for a normative understanding of the relation between powers, effects and domains.
2.3 Evidence from Book 1
A striking feature of the chestnut passage is that Socrates gives the impression of introducing into the discussion a somewhat technical notion and yet Glaucon seems easily able to understand precisely what is meant. This combination is readily explained if Plato is using it to signal that he here has Socrates deploy a notion developed, but not so prominently signalled, elsewhere. If, as I shall argue, earlier in the dialogue, we find an understanding of what a power is that can illuminate the subsequent identification of knowledge and belief as powers, there is reason to hold that this earlier understanding should act both as a resource for and as a control on our interpretation of that subsequent identification. The ease with which Glaucon understands Socrates’ somewhat technical notion makes sense if one bears in mind the conversation between Socrates and Thrasymachus to which he was witness back in Book 1 and to which we know both he and his brother were paying close attention.Footnote 17
The context of the Book 1 passage I am interested in is the discussion of crafts or skills (technai). Socrates and Thrasymachus agree that ruling is a skill. They disagree over whether, as a skill, ruling will benefit the subjects over which it is exercised or the ruler who exercises the skill. At 340d–e, Thrasymachus had insisted on a strict understanding of who counts as the practitioner of a skill. The practitioner of a skill, strictly and properly speaking, is one whose exercise of the skill does not deviate from the skill. This is why rulers who make a mistake as to their own advantage and do not properly legislate for it do not constitute an objection to Thrasymachus’ view that justice consists in the advantage of rulers. Such errant rulers do not count as rulers, properly speaking.
At 345c1, Socrates begins a sequence of argument in which he exploits Thrasymachus’ strict understanding of skill to argue that benefits resulting from activities external to the exercise of a skill do not constitute a benefit of the skill as such. For example, since money making is external to the exercise of medicine, benefits that accrue to a doctor from the making of money in connection with the practice of medicine do not count as a benefit of medicine. My concern here is not the legitimacy of Socrates’ argument, but the picture of skill that he develops as part of it.
A skill – like a power in Book 5 – has a domain over which it is set. Socrates’ language for this relation precisely mirrors that of Book 5.
The shepherding art in fact has concern for nothing else than that over which (epi) it is set (tetaktai), how to procure what is best for this.
This common characterization of skills and of powers is not surprising, since what is distinctive of skills, in Socrates’ view, is precisely their having a certain power. This does not mean that powers just are skills. Rather, skills are a sub-class of powers.
Don’t we each time say that each of the skills is different in virtue of this, having a different power (dunamis)?
Each skill provides its own benefit (ōphelia): medicine, for example, provides the benefit of health; navigation that of safety in sailing (346a6–8). But the exercise of a skill need not be the only way in which the relevant benefit may be produced. Socrates provides an example where this is not the case. Suppose a navigator, while exercising the skill of navigation, came to be healthy as a result of his being relevantly advantaged by sailing. Still, Socrates says, one would not for this reason identify navigation as medicine (346b2–6).
Socrates is not specific as to what more precisely one should say about the relevant determining relation between skill and relevant benefit. A skill should presumably offer a reliable and regular way of producing a benefit and should do so non-accidentally. The best way to account for this, I suggest, is to situate the relation between skill and benefit in a normative framework: the norms of the skill – what counts as correct performance of it – relate to the successful production of said benefit.Footnote 18 Unlike the skill of medicine, successful exercise of the skill of navigation is not determined by the production of health. Thus, although it is possible for health to result from an exercise of navigation, health is the benefit of medicine, not of navigation.
The benefit of a skill, Socrates says, is ‘its own’ (idion), not ‘common’ (koinon) (346c2–3). Given the context, this cannot mean that the benefit of a skill is unique to it in the sense that only the skill in question can cause its production. That is directly contradicted by the example of the navigator restored to health by sailing. At most, what is unique is the relation between a skill and its own benefit: the reliability of the skill’s production of the benefit in question, the way in which that production sets standards for the skill.Footnote 19
The distinctive relation between a skill and its own benefit may be compared with the way in which Socrates later characterizes the ergon of whatever object may have one.
Then do you suppose an ergon – of a horse or anything else – to be this: whatever a person does or does best with this alone.
Now, then, I think, you better understand what I was just now asking, when asking whether this would not be the ergon of each thing: whatever something effects (apergazētai) either alone or most excellently in comparison to other things.
Socrates gives two illustrations. The erga of eyes and ears are seeing and hearing respectively. These erga are unique: seeing can be done only with one’s eyes; hearing can be done only with one’s ears (352e6–11). However, despite this first illustration, Socrates’ conception of an ergon is not as unique. The ergon of a pruning knife is pruning (taking cuttings from plants). This ergon is not unique. Many kinds of knife can be used to prune. But a pruning knife is the most effective equipment to use (353a1–8). As Socrates says, it has been ‘worked to this purpose’ (tōi epi toutōi ergasthenti, 353a4–5). An ergon is unique only in the sense that it is uniquely specialized; it alone is specially assigned to the task in question. This is comparable to the point I made earlier regarding the military example: the distribution of erga avoids redundancy if an ergon is the special task of only one thing.
What is the relation between an ergon – the focus of 352e3–4 and 353a9–11 – and a benefit, on which Socrates focused earlier in this Book 1 discussion? The following passage, from that earlier discussion, helps to illuminate this relation.
Then it’s not the case that each person has this benefit – the getting of payment – as a result of his own skill: rather, if one must consider the matter precisely, medicine produces health, whereas the mercenary art produces payment; building produces a house, whereas the mercenary art, accompanying it, produces payment; and in this way all the other skills each effect their work/function (to autēs hekastē ergon ergazetai) and benefit that over which (epi) they are set (ōphelei ekeino eph’ hōi tetaktai).
346d1–6 accords each skill a domain of operation. The domain of medicine, for example, will include sick bodies. Skills benefit; but the burden of Socrates’ argument has been to establish that the recipient of the benefit in question is not the practitioner of the skill, but the items in its domain. The benefit of medicine is health; objects in the domain of medicine – sick bodies – gain the benefit of health. In this passage, a skill’s production of benefit coincides with its effecting its work or function (its ergon). This suggests that, where a benefit exists, to produce the benefit is to effect the work of the skill: to produce health is to effect the work of the skill that is medicine. This does not mean that any and every ergon is a benefit. We are entitled to conclude only that the benefits on which Socrates focuses in this discussion of skill are a subclass of erga.
One final point should be made regarding 346d1–6 before drawing this picture together. The relation between medicine and the mercenary skill described in this passage should not be projected onto the earlier example of the navigator who recovers health through sailing. There is no suggestion that this navigator exercises medicine alongside navigation. Rather, this is a case where the benefit that medicine is specially tasked with producing in sick bodies is, as it happens, brought about in such a body by the operation of a different skill.
Should the action of the navigator on his own sick body be thought of as an exercise of the skill of navigation? Certainly, there is an exercise of navigation on the relevant occasion (and there is no exercise of medicine). Presumably, it is an exercise of navigation that, in addition to causing the non-medically enabled recovery of health, effects the specialized task of navigation, safe voyage. A situation in which navigation produces health alongside safe voyage is the sort of situation in which Aristotle might appeal to his notion of incidental causation and a mediaeval thinker to the notion of double effect. Socrates gives no specific advice here. I shall call the navigator’s production of health in this instance an atypical result of the skill of navigation. Note, however, that ‘atypical’ is not here meant as a statistical notion. Though the outcome of this exercise of the skill of navigation may be atypical – it is not what the skill is for – the exercise counts as navigation and thus as an exercise of the skill of navigation no less for all that.
All Socrates needs for his argument against Thrasymachus is this notion of an atypical result: Thrasymachus, presumably, wanted to argue that acquisition of benefits such as power and money and so forth is not merely a possible atypical result of ruling, but the task to which ruling is assigned and hence constitutive of its best understanding. Further, while the atypical result of navigation that Socrates gives as example involves the production of health, a benefit, atypical results need not be of benefit. Socrates might agree that money is a possible atypical result of ruling,Footnote 20 in the sense of being a result that may be produced by ruling. But Socrates will think it one for whose production ruling is not in fact specifically tasked and which, in addition, would not benefit a ruler if it were so produced.
3 The Powers of Knowledge and Belief and Their Relation
Absent a verbal prefix,Footnote 21 346d1–6 unites in a single passage of Book 1 all the significant terminology of Book 5’s identity conditions for powers. With this passage before us, we are now ready to pull together the picture that emerges from the Book 1 discussion of skills that provides, I argue, the background to the discussion of powers in Book 5.
The picture is this: There exists a class of powers, of which a subclass are skills. Such powers are set over a domain and they are specially tasked to the performance of some work or function in connection with that domain; the performance of this work or function is constitutive of the power as a power; the work or function sets standards for the correctness of the operation of the power. In some subclass of cases, including but not necessarily restricted to the exercise of those powers that are skills, the performance of the power’s work or function produces a benefit that accrues to the items in the relevant domain.
Importantly, the various components of this model – the power, the domain and the work or function – do not stand in relations that exclude the possibility of other powers acting in connection with the relevant domain. Powers are not restricted to acting in their own domain and items in a domain are not resistant to the action of powers not specifically tasked for that domain. Such extra-domain action of a power is atypical in the sense of having the possibility of what I called an atypical result, illustrated by the example of navigation resulting in health. As this example shows, atypical results can exist alongside the power’s typical results. The example of navigation resulting in health is the most striking example of an atypical result, but one might extend this characterization to other examples that Socrates has suggested. Consider, for example, what should be said of successful pruning accomplished by a carving knife. Think of this as weakly atypical. Pruning is not the specified task of a carving knife. But carving knives and pruning knives share a task and domain conceived more broadly as the action of cutting on bodies, so that the relation between pruning and carving is considerably closer than that between navigation and medicine.
The Book 1 discussion has not provided obvious examples of what, in developing my earlier military examples, I characterized as horizontal and vertical relations between tasks in some broadly shared domain. Perhaps the relation suggested by Socrates between money making and medicine or ruling and so on might be thought of as horizontal. He certainly portrays them as acting side by side and on separate, specialized tasks. Further, Socrates’ picture is at least consistent with the existence of both horizontal and vertical relations between powers and tasks. Note that a vertical relation may coincide with atypical action. The lieutenant’s command over the soldiers in a squadron is not specifically tasked with the issuing of those orders that fall to the sergeant’s remit. The issuing of such commands would thus be weakly atypical, but would nevertheless fall within the specified authority and domain of a lieutenant’s task.
Setting vertical/horizontal relations to one side for the moment, apply the general features of Socrates’ model of powers to the Book 5 powers, knowledge and belief. As powers, knowledge and belief are specially tasked in relation to the objects of some domain: knowledge is the power to know which is tasked in relation to a domain characterized as ‘what is’, which may safely be assumed to include Forms; belief is the power to believe which is tasked in relation to a domain characterized as ‘what both is and is not’, which may safely be assumed to include those sensible features of things that are vulnerable to the compresence of opposites.Footnote 22 While these domains of objects may be distinct – even, contra Fine Reference Fine1978 and Reference Fine and Everson1990,Footnote 23 distinct and non-overlapping, as the argument of Book 5 suggests that they are – Socrates’ model of powers allows that knowledge may act in the domain of belief and belief may act in the domain of knowledge. Such exercises of knowledge and belief would, however, be atypical. That is to say, the exercise of these powers in the domain of the other would not correspond to the specific task of the power. Of course, allowing that knowledge and belief may act in each other’s domains is not the same as saying they will. The model allows that domains are not exclusive; but the specific possibilities of specific powers in respect of alternate domains must be established case by case.
There is, as Fine has argued, some textual evidence that Plato does allow the possibility of knowing in connection with objects that seem rather to be in the domain of belief and of believing in connection with objects that seem to be in the domain of knowing.Footnote 24 At 506c6–7, Socrates at least implies that he has beliefs without knowledge regarding the Form of the Good, a paradigm object in the domain of knowledge; this is precisely why he is reluctant to expound on the subject as urged to do by Glaucon. At 520c1–5, the philosopher who returns to the cave is said, as a result of his knowledge of Forms, to be in a position to exercise knowledge (gnōsesthe, c4) of ‘the images’ (eidōla, c4) to be found there; the images in question are naturally thought of as objects proper to belief.Footnote 25 The evidence of these passages is certainly defeasible.Footnote 26 But, as I said at the beginning, there is at least one contextual reason why Plato ought to allow for knowledge in relation to the objects proper to belief, for it is hard to see the benefit of philosopher rulers having knowledge, if it does not enable them to know, for example, of some particular action that it is just.Footnote 27
Note that it is not enough to say – as traditional ‘two world’ interpreters do say – that knowledge of Forms ensures that the returning philosopher will have true beliefs about the justice or injustice of particular actions.Footnote 28 If the power of knowledge can be exercised only in relation to Forms and belief is the only power that can be brought to bear on Forms’ sensible images, then it would, I submit, be a mystery why knowledge – the power or its exercise in relation to Forms – would have this consequence for exercises of the knower’s power of belief. It does not follow from the fact that sensible images of Forms are images, for this is a metaphysical relation between Forms and sensibles, but an explanation of such a consequence of knowledge for belief would be required to forge a connection between the contents of exercises of knowing and believing.Footnote 29
Here is what I would propose happens when a knowledgeable philosopher encounters a particular action that is just, albeit just only in some specific and qualified respect. The philosopher recognizes the justice of the action in the relevant respect, while at the same time recognizing that the justice of the action is merely a qualified instance of justice and as such has features specific to its context that should properly be distinguished from justice. (The instance may, for example, be a case of returning what one owes – a just case of doing so.) In such a philosopher’s recognition, there is a perfectly proper exercise of knowledge, in relation to an item squarely in the domain of knowledge, the Form of Justice. That such a knower would have the Form in mind when regarding particular instances is, I think, the clear implication of two passages: (1) the earlier characterization of a knower as being awake, and as ‘capable of observing both [the Form] and the things that partake of it’ and not, like the dreamer, mistaking one for the other (476c7–d2);Footnote 30 (2) the later characterization of the returning philosopher as recognizing the images in the cave as images and as the specific images they are ‘as a result’ (dia), as Socrates says, of their having seen the truth regarding Forms (520c3–5).
That the knower who recognizes the justice of an individual action exercises her knowledge of the Form indicates, as I earlier suggested, that the special object of knowledge acts as a medium for such extra-domain activity in much the way that colour acts as a medium of seeing. But should one in addition think of this knower as knowing of the particular act in question that it, the act, is just? It is not clear to me what else one could reasonably call their cognitive relation to this fact. But such exercise of the power of knowledge would be at least weakly atypical: it is not the special task of knowledge to know particular instances, though the power can do so.Footnote 31 However, though a (weakly) atypical exercise, it is an exercise of knowledge and counts as knowing nonetheless.
One certainly should not think of a knower’s recognition of the justice of an individual action as an exercise of believing, for belief is used in the context to designate the activity of the person from whom the knower is sharply distinguished. Indeed, it is used in context at least in part to signal the activity of one with confused pretensions to knowledge. This aspect of belief causes some complication for the project of stating with any clarity what the normative task of belief should be understood to be. In the context, Socrates seems to be doing two things at once: identifying belief as a power, which suggests it has an assigned task in relation to the objects in its domain, and at the same time admonishing belief for its pretensions to knowledge.
My own guess as to what should be said more specifically about the power belief is that belief is some kind of general perceptual power.Footnote 32 That is to say, sight and hearing – Socrates’ initial examples of powers in the Book 5 passage – are not mere examples, but closely related to belief. Support for this thought comes from the fact that the lovers of sights and sounds addressed by the argument are to be determined as, not philosophers, but philodoxers or lovers of belief (480a6–7). But their official designation as lovers of sights and sounds already makes clear their attachment to seeing and hearing. This in turn may help to explain Socrates’ use of sight and hearing as examples of powers, though their own special objects (colours and sounds) are cognitively inaccessible to the other in a way that, as I argue, the objects of knowledge and belief are not.
Socrates’ characterization of the objects of the domain of knowledge and those of belief suggests a relation between them: the domain of knowledge is what is; that of belief what both is and is not. Understood as including on the one hand, Forms, and on the other, participants, the connection between the domains is underpinned by a metaphysical relation between these objects within them. Given this, it is tempting to ask whether there is a vertical relation between the powers of knowledge and belief, so that the authority of knowledge would extend to include objects in the domain of belief, though its exercise in relation to them would still be atypical. Some slight suggestion of such a vertical relation might be seen in Glaucon’s claim, at 477e1, that, knowledge is not only a power, but is ‘most formidable (errōmenestatēn) of all powers (dunameis).’ It is not clear what formidableness will amount to in this context. But it is clear that knowledge is being accorded greater force than other powers, and in the immediate context, specifically than the power, belief. This implies some common ground for competition and comparison.
If knowledge and belief stand in a vertical relation, then, while knowledge will have the authority to reach down to the domain of belief albeit in atypical exercise, an attempt on the part of belief to reach up to the domain of knowledge will be an act of usurpation. The lovers of sights and sounds with their pretensions to knowledge would exemplify such misapplication of belief. In contrast, Socrates’ later reluctance to expound on the Form of the Good from a position of beliefs without knowledge would demonstrate appropriate restraint.
Much more would need to be said to defend the details of this proposal, especially these closing, speculative remarks about the character of belief and the possibility of a vertical relation between it and knowledge. I do not claim to have shown that this way of developing the model of powers one gets from putting Book 1 and Book 5 together is the only one available. The main point I would insist on is the importance of putting together Book 1 and Book 5 and, once one has done so, the evidence it provides that the domains of knowledge and belief are not exclusive in the way required for the reading of the chestnut according to which the power that is knowledge or belief can be exercised only in relation to items in the domain over which it is set as a power
4 Conclusion
Socrates is explicit that the domains of knowledge and belief are distinct and in terms that suggest that he thinks the two domains are distinct and non-overlapping.
Does [belief believe] the same thing that knowledge knows? And will the same thing be both knowable and believable? Or is that impossible?
Impossible, he said, on the basis of what has been agreed.
On the view I have proposed, what this means is that the domains of objects for which knowledge and belief are each specially tasked as powers are distinct and my view allows (though does not require) that the domains are distinct and non-overlapping. For something to be ‘knowable’ or ‘believable’ is for it to be such that knowledge and belief are specially tasked in relation to it. But this does not mean that objects in the domain of knowledge or of belief are for that reason cognitively inaccessible to one another.
The conclusion at 478a11–13 follows from the agreement that knowledge and belief are different powers combined with the principle for individuation of powers announced in the chestnut passage (477c1–d7, translated in Section 1). In the chestnut passage, Socrates stipulates identity conditions for powers according to which different powers are uniquely tasked.Footnote 33 Given these identity conditions, Socrates does not make a fallacious inference in inferring that, as a distinct power from knowledge, belief must be set over something distinct from that which knowledge is set over. Nor, however, does Socrates simply arbitrarily stipulate such identity conditions for the powers, knowledge and belief. Rather, he spells out the identity conditions implicit in the earlier model according to which what a power is – and what, accordingly, it effects – is a function of the domain for which it is normatively tasked and vice versa. Though Socrates’ identity conditions involve two components – the domain and the effect – linked by ‘te’ (‘both’) and ‘kai’ (‘and’) (477d2) – he appears to treat them as a unit when he describes himself as individuating powers by looking only to this (singular), followed by the pair (477d1–2).Footnote 34
Socrates allows, then, that the same thing may be both known and believed. Does knowledge, in Socrates’ understanding, entail belief? If this is the question, ‘Does Socrates’ conception of knowledge incorporate an attitude of conviction, a holding to be true?’, there seems no reason to deny this. But when Socrates individuates the power, belief, from the power, knowledge, it is not clear to me that belief is best understood in the way that modern epistemologists understand it, as the attitude of regarding as true, though Socrates’ power too no doubt incorporates such an attitude.Footnote 35 My speculative proposals as to the character of belief as a perceptual power and of a vertical relation between it and knowledge would allow that knowledge and belief could, at least in certain circumstances, combine and collaborate. This may explain why Socrates speaks of ‘beliefs without knowledge’ (tas aneu epistēmēs doxas, 506c6) in a way that strongly suggests a contrast to beliefs with knowledge. But, since knowledge and belief are, on the view I propose, differently tasked, a relation between them could not, I think, be one of logical entailment.
I close by noting some main points of difference between my view and others that have been proposed.Footnote 36 Like Fine, I reject ‘the Two Worlds Theory’ when understood as she understands it, as the view that ‘there is knowledge only of Forms and belief only about sensibles’.Footnote 37 Like Fine, I take it to be perfectly possible for a philosopher-ruler to know of some particular (qualifiedly) just action that it, the action in question, is (qualifiedly) just.Footnote 38 Unlike Fine, however, I take knowing of a particular just act that it is just to be an atypical exercise of knowledge in the sense I have explained (though an exercise of knowledge nonetheless). Beliefs about Forms will also be atypical and, if regarded as having authority, inappropriate. Like traditional two-world readers, I take the domains of knowledge and belief to be distinct and (at least arguably) non-overlapping, and not, as Fine does, as sets of contents that are distinct, but overlapping. But I understand the consequence of this distinctness in a way quite different from the traditional two-world reading. The domains of knowledge and belief are not exclusive; the objects of knowledge and belief are not cognitively inaccessible to the other. There is a way in which knowers and (mere) believers occupy different worlds, cognitively speaking: regarding the justice of a particular just act, their cognitive contents differ, since one sees an image of the Form of Justice as an image of the Form of Justice, the other does not. But there is nothing to prevent their having their attitudes to one and the same object: a (qualifiedly) just particular action.Footnote 39
