Language, thought and the epistemictheory of vagueness

Frank Jackson*

Research School of Social Sciences, The Australian National University, Canberra, ACT 0200, Australia

Abstract

There are borderline cases of baldness, cases where we are in principle unable to say whe-ther or not a subject is or is not bald. According to the epistemic theory of vagueness, when X

is on the borderline, ‘X is bald’ either is true or is false, and X either definitely is or definitely isnot bald, though we cannot determine which it is. There is, that is, such a thing as the correctverdict but we cannot tell which one it is. I argue that the role of language in communicatingour thought about how things are makes a strong argument against this theory. # 2002

Published by Elsevier Science Ltd.

Keywords: Vagueness; Meaning and use; Epistemic theory of vagueness

1. Introduction

Pink things sometimes turn red over time. Sunrises are an example. When theyturn red, it often happens that there is a stage at which it is in principle unclearwhether to say that the thing in question is red or to say that it is still pink althoughwell on the way to becoming red. Men often turn bald over time. When they do, itregularly happens that there is a stage at which it is in principle unclear whether tosay that they are bald, or to say that are still hairy although well on the way tobecoming bald. In both cases, we have the phenomena of borderline cases char-acteristic of the vague. When F is vague, there will be cases—the borderline ones—where it is unclear whether to say that something is F, or to say that it is not F.Borderline cases are ones where verdicts seem in principle hard if not impossible tocome by.

Language & Communication 22 (2002) 269–279

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E-mail address: frank.jackson@anu.edu.au (F. Jackson).

This paper offers an objection to the epistemic theory of vagueness. According tothis theory, at every stage during Fred‘s gradual hair loss, it is either (determinately)the case that he is hairy or (determinately) the case that he is bald. What makes astage a borderline one is nothing more than the fact that we cannot tell which—determinately hairy or determinately bald—is the case at that stage. More generally,the idea is that the borderline cases characteristic of vagueness are the ones where,although something either is F or is not F, it is epistemically opaque which it is. Ourobjection to the epistemic theory will be based on a certain view about the relationbetween thought and language; in particular, that part of the correct account of thatrelation must include the role of language in communicating how we take things are.The epistemic theory of vagueness is the least popular theory of vagueness; it

‘feels’ wrong. But it has proved surprisingly difficult to produce an argued objectionto it. And Timothy Williamson notes in the preface to (1994) that his inability tofind a good argument against it was a major factor in his becoming a supporter ofthe epistemic theory. I hope that this paper fills the gap; it offers an argumentagainst the epistemic theory.I start by giving a little more detail on the phenomenon distinctive of vagueness on

which we will be focussing. I then survey three ways of explaining this phenomenon,including that offered by the epistemic theory. Next, I advance the main business ofthe paper, the objection from communication to the epistemic theory of vagueness.The paper concludes by replying to some objections to this objection.

2. The epistemic opacity of sentences containing vague predicates

The phenomenon which I will be arguing makes serious trouble for the epistemictheory of vagueness concerns language, whether written or spoken, although Iintroduced it in terms of saying at the beginning.If you ask me whether the sentence ‘Fred has an odd number of hairs on his head’

is true, or whether it is false, I will have trouble answering the question. But there istypically no mystery about why this is the case. The reason will be that I have notdone the needed research. Were I to take the time and trouble, and were I not to losecount, and supposing that Fred’s head does not contain structures that fall on theborderline between being a hair on his head and not being a hair on his head, I coulddeliver the answer with confidence. However, if Fred’s head falls on the borderlinebetween the hairy and the bald, I will not be able to answer with confidence whetherthe sentence ‘Fred is bald’ is true, or whether it is false. And this is true no matterhow much research I do on the number and distribution of hairs on Fred’s head andno matter how carefully I count or measure the gaps between the various hairs.This is puzzling. It is agreed that facts about number and distribution of hairs on

heads are the facts that matter for whether or not someone is bald. We agree thatbaldness supervenes on the number and distribution of hairs on heads: heads alike innumber and distribution of hairs are alike in whether or not they are bald heads.Moreover, in lots of cases, information about number and distribution of hairs doessettle definitively questions about baldness: someone with less than six hairs on their

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head is, beyond question, bald; someone with so many hairs that you cannot see anyof their scalp is, beyond question, not bald. Why the difficulty in certain casesdespite full information concerning the data which is agreed to be the relevant data?Let’s say that a sentence is robustly epistemically opaque when it resists truth-

value determination in the face of full determination of all relevant information.Thus, in the case as described, ‘Fred is bald’ is robustly epistemically opaque whenFred falls on the borderline between bald and not bald. In the same way, somesentences of the form ‘X is pink’ are robustly epistemically opaque. Although onereason I may be unable to say whether a sentence of this form is true or whether it isfalse is that I may not have seen X, or may know that there is a problem with mycolour vision, another reason may be that, despite being able to see X perfectly well,knowing that my eyes are working well and that conditions are good for seeingcolours, X is on the borderline between pink and red. The same goes for ‘X is ashrub’, ‘X is a town’ and so on.

3. Three ways of explaining the epistemic opacity of the vague1

The two most popular ways of explaining why ‘Fred is bald’ resists truth-valuedetermination when Fred is on the borderline agree that there is no truth-value to bedetermined. When Fred on the borderline, ‘Fred is bald’ is neither true nor false; it isindeterminate. Little wonder, run these two explanations, that we cannot tell whe-ther it is true or whether it is false, for it is neither.The difference in the two explanations arises from a difference in how, when Fred

is on the borderline, the lack of truth-value is explained. The first explanationexplains the lack of truth-value in semantic terms.2 It accepts the metaphysicalprinciple that to be is to be determinate. There is no indeterminacy in re. In parti-cular, for any property in the sense of a way something might be, including dis-junctive ways things might be, and any object, it either is (determinately is) or is not(determinately is not) the case that the object has the property. (This principle isindependent of issues about the metaphysics of properties. It does not matter ifproperties are sets, or are sets of objects that resemble each other to some degree orother, or are Platonic universals, or are sets in logical space, or. . .) Now, if there isno indeterminacy in reality, runs this explanation, the reason why ‘Fred is bald’lacks a truth-value must lie in the semantics of the sentence. And the offeredsemantic explanation of the indeterminacy of ‘Fred is bald’ is that there is no singleproperty that the word ‘bald’ picks out in the sense of being the property we ascribewhen we use the word in sentences of the form ‘X is bald’. Rather, there is a range ofproperties, each of which is an equally good candidate to be the property ‘bald’picks out. And when Fred is on the borderline between bald and hairy, he has some

1 See Williamson (1994) for a fuller inventory and references. For our purposes here, we need only

enough detail to set the scene for our critique of the epistemic theory.2 The classic source for the view that vagueness is a semantic phenomenon, or more generally a feature

of representation, is Russell (1923).

F. Jackson / Language & Communication 22 (2002) 269–279 271

but not all of them—which is what makes it the case that he is on the borderline.And because Fred has some but not all of the equally good candidates to be thatwhich ‘bald’ picks out, the sentence does not count as true and does not count asfalse.3

Why is there a range of properties equally eligible to be the property the word‘bald’ picks out? The answer is semantic indecision; the borderline cases are simplycases about which we have not decided whether they fall inside or outside the classof the things that count as bald. Of course, we can make a decision that some caseon the borderline for standard English is to count as bald in English*, much as townplanners sometimes adopt fairly precise definitions of what counts as a town, andbotanists do the same for a term like ‘shrub’. In that case, if Fred falls under thatcase, ‘Fred is bald’ would be true in English*. It is because no such decision has beenmade for English that ‘Fred is bald’ in English lacks a truth-value.There is, in this account, no indeterminacy in re. For each property in the range of

equally good candidates to be the property picked out by ‘bald’, it is determinatethat Fred has it, or that Fred lacks it. Also, it is determinately true that there is arange of equally good candidates in the same way that it may be determinately truethat two points are equidistant from a third. And there is no mystery about whysomeone with, for example, less than six hairs on their head is determinately bald;for every eligible candidate to be the property picked out by the word ‘bald’, headswith less than six hairs possess that property.The second explanation denies the principle that to be is to be determinate. It

insists that, when he is on the borderline, Fred’s very nature is indeterminate; whichis why the sentence is neither true nor false. Fred is, that is, on the borderlinebetween the bald and the hairy in the sense of having an indeterminate nature, not inthe sense of having a determinate nature which falls into a region of semantic inde-cision concerning our use of the word ‘bald’. And his indeterminate nature is why‘Fred is bald’ fails to be true and fails to be false, and is thereby indeterminate intruth-value.4

As a believer in the doctrine that to be is to be determinate, I reject vagueness inre. But let me mention an objection to the explanation of epistemic opacity interms of vagueness in re that can be posed without reference to this doctrine inmetaphysics.Vagueness comes in degrees. ‘Fred’s head has such and such hair distribution’ is

vague. This is because there are borderline cases for being a hair, and also for beingon Fred’s head rather than his neck. But ‘Fred is bald’ is vaguer. Similarly, although‘X is taller than Y’ is vague, ‘X is tall’ is vaguer. But changing the words we usecould not change how much vagueness in re there is; that is common ground surely.A problem for the second explanation of the epistemic opacity of the vague is,

3 According to Williamson, this approach to lack of truth-value in terms of having some but not all

candidates goes back to Mehlberg (1958). The version sketched here is closest to Fine (1975) and Lewis

(1970).4 This view has undergone something of a revival in recent years; for references, see Williamson (1994),

Chapter 9.

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accordingly, how to explain why some sentences are vaguer than others in terms ofan alleged phenomenon that is agreed not to change with change in language.The third explanation of the epistemic opacity of vague sentences draws on the

epistemic theory of vagueness. This theory, as we saw, insists that the sentence ‘Fredis bald’ has a determinate truth-value for all the possible distributions of Fred’s hair,including the ones on the borderline between bald and hairy. However, although thesentence has a determinate truth-value and we have all the information which isagreed to be of the kind which is relevant to settling that truth-value, we cannot, as amatter of principle, determine that truth-value. The same goes for sentences of theform ‘X is pink’, which the first two theories hold lacks a truth-value when X fallssomewhere on the border between red and pink. According to the epistemic theorist,these theories mistake a truth-value which is epistemically inaccessible for one that isabsent.There is a sense in which the epistemic view denies that there are borderline cases.

Each head is determinately in the bald class or not in the bald class. There are noheads literally on the borderline; instead, they appear to be on a borderline by virtueof its being impossible to tell which class they fall into. In the same way, nothing isliterally on the boundary between red and pink. Everything which is either red orpink is determinately red or determinately pink; there is an appearance of inde-terminacy in the cases we call ‘on the border’ due to the fact that we cannot tell inthese cases which they are: determinately red, or determinately pink. Accordingly,we could regard the epistemic theory as an eliminativist view of vagueness. This is,however, a verbal issue and nothing that follows turns on it.A more important issue is whether the epistemic theory can explain the location of

robust epistemic opacity. There is no robust epistemic opacity in the region of somehair distributions. For example, those with about six hairs on their heads are forsure bald. Likewise, those with so many hairs that we cannot discern their scalpsbetween the hairs are for sure not bald. But somewhere in between there are theborderline cases. A fair question is why are the borderline cases located where theyare?The semantic approach has an explanation in terms of certain a posteriori

semantic facts. It is an empirical fact that we did not make the semantic decisionabout what to say in terms of the word ‘bald’ for those hair distributions somewherein the middle. In the same way, if we are asked why a certain plant is on the bor-derline between a shrub and a tree, the answer will be that the plant is in the regionwhere we have not made the needed semantic decision. We could have but wehaven’t.The indeterminacy in re approach can appeal to the location of the relevant inde-

terminacy in re. Our plant has, as a matter of fact, an indeterminate nature and thatis why it is on the border between a shrub and a tree. However, it is quite unclear, itseems to me, how epistemic theorists could explain the location of the robust epis-temic opacity. This is because it is quite unclear what that location is determined by,what grounds it.Be this as it may, I now turn to our main business, the objection from commu-

nication to the epistemic theory.

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4. Communication and the epistemic theory of vagueness

I start with some ‘reminder’ remarks about language, thought and communica-tion.5 The point of objection to the epistemic theory comes a little later.Declarative sentences typically serve to communicate how we take things to be.

The sentence ‘Mary Pierce won’ in the newspapers the day after the French Open of2000 communicated something about how things are according to the journalistswho wrote the stories, something which made many French readers very happy butmade many Spanish ones less so. The same goes for ‘Fred is bald’. We use it tocommunicate how we take things to be. There is a reason why Fred gets upset whenhe hears sentences like ‘You are getting bald’, and it is to do with what, and hisknowledge of what, such sentences say about the speaker’s opinion as to how thingsare with his head (combined with his suspicion that they are right).How does a sentence get to serve the task of being suitable for making claims

about how users of the sentence take things to be? This is a large question. But, forour needs here, what is crucial is one part of the answer to this large question. If asentence is to serve the task, parts of the sentence must be associated with howthings are. If no-one has a clue about what the word ‘won’ stands for, it would beinexplicable why French people were very pleased when they read, or heard, ‘MaryPierce won’—they might just as well have read ‘Mary Pierce glubbed’. Equally, therewould be no explanation as to why journalists chose the one sentence over the otherin their report of what happened at Roland Garros.The point applies equally to ‘Fred is bald’. In order to explain its role in commu-

nication, we must inter alia know which property the word ‘bald’ picks out. Other-wise, we cannot explain why hearing the sentence is upsetting to Fred, whereashearing, say, ‘Your second serve is getting better’ has the opposite effect. Equally, anexplanation of our choice of the sentence ‘Fred is bald’ as the one to utter on seeinghis head depends inter alia on our view about the nature of his head and our view asto what property the word ‘bald’ picks out.What property is it, then, that we (and Fred) know is the one ‘bald’ picks out, the

one we are ascribing when we use sentences like ‘Fred is bald’? There seems to beonly one plausible answer; the property is that of having a certain kind of hair dis-tribution. This certain kind of hair distribution will be a disjunctive one, of course. Itis common ground that there are many particular hair distributions that constitutebeing bald. That is to say, ‘bald’ picks out being H1 or H2 or . . . Hn, where the H’sare the various hair distributions that count as being bald.For what are the alternatives to holding that ‘bald’ picks out a certain (dis-

junctive) hair distribution? That we ascribe the applicability of the word ‘bald’ inEnglish to Fred? But that is not what upsets him. Words don’t break bones. Whatupsets Fred is the ascription of what the word signifies, not the word’s applicabilityper se. That there is some property distinct from any hair distribution and it is that

5 For versions of what the reminder is a reminder of, see, e.g. Grice (1957), Lewis (1969) and Bennett

(1976). The classic source is Locke (1690). The accounts given by these authors vary in important ways

but not in ways that affect the argument to follow.

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property we are ascribing? But this is uncomfortably like Moore (1929, Chapter 1)on goodness; we have an indefinable property which, first, we have no reason tobelieve is instantiated, and, secondly, which mysteriously supervenes on the proper-ties we do have reason to believe are instantiated, namely, the various hair dis-tributions. There is, that is, no plausible alternative to holding that we know thatword ‘bald’ picks out some (disjunctive) hair distribution.Now we can state our problem for the epistemic theory. There is nothing espe-

cially opaque about hair distributions. But this means that the property the word‘bald’ ascribes is not one that displays (robust) epistemic opacity. How then can it beopaque whether or not ‘Fred is bald’ is true?6

At one level, the answer is obvious. It can be opaque because although it may beclear that ‘bald’ picks out some hair distribution or other, there may be a region ofindeterminacy about exactly which distribution it picks out. The trouble is that thisresponse is not available to epistemic theorists. This response is, in effect, thesemantic explanation of vagueness. But epistemic theorists hold that ‘Fred is bald’has a determinate truth-value for each and every particular hair distribution he mayhave. This means that they must hold that the word ‘bald’ picks out, determinatelypicks out, a disjunctive hair distribution (got in fact by disjoining all the particularones for which ‘Fred is bald’ is true). And we can determine whether or not Fred hasthis hair distribution and so, contrary to the datum to be explained, make it trans-parent for each hair distribution Fred may have, whether or not Fred is bald whenhe has that hair distribution.There is obviously more to say about this objection. I have put the ‘more to say’

into the relevant places in the replies to objections.

5. Reply to objections

(1) ‘‘If you are right that we know what property the word ‘bald’ picks out andthat it picks out something epistemically accessible, namely, a certain disjunctivehair distribution, ‘Fred is bald’ cannot be epistemically opaque. You are committedto denying the datum we started from!’Reply I can say something which epistemic theorists cannot say. I can say, fol-

lowing the semantic explanation of the epistemic opacity of the vague, that there isno such thing as the property the word ‘bald’ picks out. There is, rather, a range of(overlapping) properties, each equally eligible to be the property picked out by theword ‘bald’. When Fred falls on the borderline between the bald and the hairy, hewill have some but not all of these properties, and this is how ‘Fred is bald’ fails tohave a truth-value. Had he had the lot, he would be determinately bald; had he hadnone, he would be determinately not bald; as it is, there is no determinate answer. Ifthis is right, what we communicate when we use a sentence like ‘Fred is bald’ is

6 More precisely, the problem is that the epistemic opacity of hair distribution is much less than that of

baldness; see the discussion of the last objection below.

F. Jackson / Language & Communication 22 (2002) 269–279 275

indeterminate to the corresponding degree. But, far from being an objection, thisseems to be the simple truth of the matter.(2). ‘‘You are right that epistemic theorists are committed to holding that ‘bald’

picks out some single property, but it does not follow that the possession of thisproperty is what competent speakers communicate when they use the word. Epis-temic theorists can insist that there is some single, no doubt disjunctive, hair dis-tribution property corresponding to the word ‘bald’. It is this property’s possessionor absence on any given occasion that secures the determinate truth-value that ‘Fredis bald’ always has according to them. At the same time, they can insist that wecannot in principle know what that property is in the sense that we cannot knowwhat property it is exactly. We can only know that it is one of a range of properties.This means that what, according to them, we communicate when we use the word‘bald’ is that some head has a property in the range—much as you yourself sayabove.’’Reply I think we should deny the posited divorce between what we competent

speakers use the word ‘bald’ to communicate and what the word ‘bald’ picks out.When we learn a word like ‘bald’, we learn to use it to say something about how wetake things to be. The idea that there might be a range of hair distribution propertieswhich (a) contains the disjunctive distribution that ‘bald’ really picks out, and (b)which is such that, in principle, no speaker, no matter how competent with the term,is able to say which one it is, falls prey, it seems to me, to the challenge, What makesit true that ‘bald’ picks out that one rather than this one?7

It is important here to remember the earlier point that we should not be Mooreansabout baldness; we should not hold that baldness is an indefinable, non-naturalproperty akin to goodness as Moore conceived of it. Epistemic theorists who holdthat there is a single property of baldness, the property ‘bald’ picks out, as opposedto a range of properties each equally eligible to be a property picked out by theword, must, in the interests of avoiding metaphysical mysteries, hold that the prop-erty picked out is some hair distribution or other. But then it is a fair question to askwhat makes it true that the word picks out one distribution rather than another—asthey are committed to holding by virtue of holding that ‘Fred is bald’ has a deter-minate truth-value throughout the sad history of his hair loss. It is this questionwhich, I am urging, epistemic theorists cannot answer if they sever the connectionbetween what property gets picked out by the word ‘bald’ and what we claim andcommunicate about how some head is when we use the word ‘bald’.There is a second problem for the ‘divorce’ view, the view that ‘bald’ picks out

some precise hair distribution but that all we communicate when we use the word issomething that is imprecise in principle. It arises from a point Locke makes aboutvoluntary signs.When a man speaks to another, it is that he may be understood; and the end of

speech is that those sounds, as marks, may make known his ideas to the hearer. . . .

7 Some would offer a causal story here, but this is not something epistemic theorists can embrace. For

once the causal facts were in, we would be able to settle the truth-value of ‘Fred is bald’ in the cases where

they hold such a determination is impossible.

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Words being voluntary signs, they cannot be voluntary signs imposed by him onthings he knows not. That would be to make them signs of nothing, sounds withoutsignification. (Locke 1690, Book III, Chapter II, Section 2, my emphasis)Locke’s point is that we could not have entered into an agreement to use ‘bald’ for

some precise hair distribution if baldness is, as a matter of principle, epistemicallyinaccessible in the region around that precise distribution. We could not know whatwe are agreeing about.It might be suggested that the phenomenon of semantic deference shows that there

must be something wrong with my reply to the second objection.8 Suppose that Fredknows very little about quarks but believes that what physics experts say about theirexistence is correct and defers to their expertise. Obviously, he communicatessomething about how things are when he says ‘There are quarks’. But he can hardlybe communicating anything other than that there are things of the kind that modernphysics calls ‘quarks’; that’s all he knows. Nevertheless, runs the objection, the word‘quark’ in his mouth picks out entities that fall under the physics experts’ concept ofa quark, and the sentence in his mouth will be true if and only if there are things thatfall under that concept.I have two responses. The more controversial one is to deny the view about the

property the word ‘quark’ in Fred’s mouth picks out. I think ‘quark’ in Fred’smouth picks out the property of being what the physicists call ‘quarks’. The fact thatFred defers to the physicists does not mean that ‘quark’ in his mouth picks out thesame property as it does in theirs, or that his concept is theirs. It means simply thathe is very disposed to shift from his usage and concept to theirs when he learns whatproperty the term applies to in their mouths. (For more on this, see Jackson, 1998.)The less controversial response is to note that we could run our argument for the

experts about words like ‘bald’, ‘pink’, ‘shrub’ and ‘town’, leaving the ‘deferrers’ outof it. The experts face the problem of borderline cases every bit as much as do the‘Jones’s’ among speakers of English. Of course, town planners sometimes stipulate aprecise boundary between a town and a city, and botanists do likewise for theboundary between a shrub and a tree. But that does not bear on the problem ofvagueness for such words in ordinary English.(3). ‘‘Your argument rests on an identification of meaning with use. When all is

said and done, your key point is that competent speakers’ uses of ‘bald’ do not dis-criminate between the various hair distributions on the borderline between bald andhairy. Or, as Williamson (1994, p. 205) puts it,A common complaint against the epistemic view of vagueness is that it severs a

necessary connection between meaning and use. Words mean what they do becausewe use them as we do; to postulate a fact of the matter in borderline cases is (it ischarged) to suppose incoherently, that the meanings of our words draw lines whereour use of them does not.But there are decisive objections to the identification of meaning with use, as

Williamson goes on to argue.’’

8 I am indebted here to discussions with David Braddon-Mitchell.

F. Jackson / Language & Communication 22 (2002) 269–279 277

Reply It is true that our argument uses a version of the doctrine that meaning isuse, but there are two quite different versions of that doctrine, and the version whichhas the problems is not the version our argument uses.One thing that is sometimes meant by the doctrine that meaning is use is,

roughly, that the circumstances in which people use an expression determine itsmeaning. This version is the one Williamson attacks (1994, Section 7.5). It is reallya hangover from verificationism and faces clear counter-examples. Here is one (notWilliamson’s).The circumstances in which I assert ‘There were dinosaurs’ are the same as those

in which certain fundamentalist Christians assert ‘There were no dinosaurs but Godcreated ‘‘‘traces’’ during the six days in which He created the world which appear topoint strongly to there being dinosaurs, as a test of our faith’. It would be quitewrong to infer that the first sentence in my mouth means the same as the secondsentence in their mouths.However, the doctrine that meaning is use can also be read as the doctrine that the

meaning of a sentence is the belief or thought we use the sentence to express andcommunicate. It is this doctrine that our objection in effect employs. It is the verywidely accepted doctrine that when we give the content of a belief with a sentence,the content of the belief and the content of the sentence are one and the same. Nowthere are problems with this version of the meaning is use doctrine despite the factthat it is so much more plausible than the first version. A well-known problem isthat extremely complicated sentences can have a meaning despite the fact that we donot use them to express what we believe because they are too complicated to process.However, in the case of relatively simple sentences like ‘Fred is bald’ and ‘This ispink’, it is very plausible that their meaning is the same as the belief we express byusing them.This means that if, as the epistemic theorists hold, the word ‘bald’ draws a precise

line among the various disjunctive hair distributions, it does so by virtue of ourusing the word to convey some precise belief about which disjunctive hair distribu-tion Fred has. But the phenomenon of epistemic opacity is precisely the phenom-enon of our being clear about what we believe about Fred’s hair distribution whenhe is on the borderline while being unclear about what to say using the word ‘bald’concerning Fred.(4.) ‘‘In saying, as you just have, that we may be clear about what we believe

about Fred’s hair distribution when he is on the borderline, you forget the pointnoted earlier that there are borderline cases of being a hair on Fred’s head. There arecases where hair distribution is epistemically opaque.’’Reply I have been simplifying. The key problem from communication for the

epistemic theory of vagueness is that questions of hair distribution are much moreprecise than questions of baldness, as we noted earlier. Sentences framed in terms ofhair distribution display much less epistemic opacity than those framed in terms ofbaldness; but if the epistemic theory were correct, there should be no difference.9

9 This paper owes a lot to discussions with Michael Smith and Dominic Hyde.

278 F. Jackson / Language & Communication 22 (2002) 269–279

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