color, error, and explanatory power

dialectica

Vol. 60, N° 2 (2006), pp. 171–179DOI: 10.1111/j.1746-8361.2005.01047.x

© 2005 Editorial Board of

dialectica

Published by Blackwell Publishing Ltd., 9600 Garsington Road, Oxford, OX4 2DQ, UK and 350Main Street, Malden, MA 02148, USA

Color, Error, and Explanatory Power

Color, Error, and Explanatory Power

Jonathan E

llis

†

A

BSTRACT

Error theorists about color argue that our ordinary judgments ascribing color to materialobjects are all false. The error theorist proposes that everything that is so, including the factthat material objects appear to us to have color, can best be explained without ever attributingcolor to objects (for instance, by appealing to surface reflectance properties, the nature oflight, the neurophysiology of perceivers, etc.). The appeal of this view stems in significant partfrom the prevalent thought that such explanations are strongly suggested by our present scien-tific conception of the world. Recently, however, Barry Stroud has argued that error theoristscannot successfully even acknowledge, let alone explain, all of the facts that error theoristsmust acknowledge. In this paper, I shall raise an objection to Stroud’s argument. I shall con-clude by mentioning one way in which we might develop Stroud’s general strategy with moresuccess.

At least since Democritus, philosophers have been fond of the idea that objectsdo not ‘really’ have color. One such view is the error theory, according to whichour ordinary judgments ascribing color to material objects are all false, erroneous;no material object has color.

1

The error theorist proposes that everything that isso, including the fact that material objects appear to us to have color, can best beexplained without ever attributing color to objects (for instance, by appealing tosurface reflectance properties, the nature of light, the neurophysiology of per-ceivers, etc.). The appeal of this view stems in significant part from the prevalentthought that such explanations are strongly suggested by our present scientificconception of the world. Recently, however, Barry Stroud has argued that errortheorists cannot successfully even acknowledge, let alone explain, all of the factsthat error theorists must acknowledge.

2

In this paper, I shall raise an objection toStroud’s argument. I shall conclude by mentioning one way in which we mightdevelop Stroud’s general strategy with more success.

Stroud’s pivotal claim is that it is a necessary condition upon a person’s havingthe capacity to believe that others have perceptions and beliefs in which colors are

1

Galileo advanced an influential error theory. For some contemporary error theories,see Boghossian and Velleman (1989), Clark (2000), Hardin (1993), Jackson (1977), Mackie(1976), Maund (1995), and Perkins (1983).

2

Stroud, Barry. (2000)

The Quest for Reality: Subjectivism and the Metaphysics ofColour.

New York: Oxford University Press. Hereafter ‘QR’.

†

Department of Philosophy, Cowell Faculty Services, University of California, SantaCruz CA 95064; E-mail: [email protected]

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ascribed to objects that the person himself has color beliefs.

3

He suggests that, ‘wecan have beliefs of the one kind only because we have some beliefs of the otherkind’. (QR, 150.) What that suggests, he believes, is that one could not acknowl-edge all of the psychological facts an error theorist must acknowledge and at thesame time ‘consistently’ maintain that objects do not have color. That only seemsto the error theorist something he can consistently do, because he does not takeseriously enough the conditions on the attribution of thought and perception.

4

Stroud supports his pivotal claim by encouraging us to see for ourselves: ‘Tryto start with no beliefs about the colours of objects, make no use of any suchbeliefs anywhere, and see if you could ascribe to anyone perceptions of orbeliefs about the colour of something’. (QR, 157.) Stroud’s argument for thepivotal claim consists almost entirely in his subsequent discussion in which heproceeds to explain in considerable depth why he thinks we could not do this.

5

According to Stroud, to attribute to someone even a non-veridical perception of,say, a particular lemon’s being yellow, one must have a ‘conception’ of what aperception of that sort is, and of how it differs from other sorts of perceptions,such as a perception of a lemon’s being green. And to have that conception, onemust have a conception of the property yellow. Stroud asks how we could everacquire conceptions such as these if we did not believe that material objects havecolor.

It is tempting, for instance, to suppose that we could acquire a conception ofthe property yellow simply by attending to the features of our own color percep-tions – by consulting the colored patches of our visual field, perhaps. Stroud’sarguments against this supposition are complex. They call to mind a number ofWittgenstein’s considerations in

Philosophical Investigations

about naming sen-sations and ostensive definition.

6

Stroud traces a number of different proposalsconcerning how one might form a conception of the property yellow merely by

3

Stroud uses the terms ‘perceive’ and ‘perception’ as

not

factive, which will perhapsbe distracting for some readers. For the sake of clarity and consistency, though, I shall followStroud’s usage throughout this paper. I shall also follow Stroud in employing the term ‘colorbeliefs’ as referring to those beliefs in which color or a particular color(s) is ascribed to aparticular object(s), such as the belief that the lemon on the table is yellow. Having color beliefsdoes not require having the more general belief that objects in the world have color, though thattoo is a color belief.

4

Stroud does not intend to argue that the content of the error theorist’s claim that peoplehave beliefs in which they ascribe color to objects but these beliefs are all false is itself therebyinconsistent or in any other way necessarily false. Stroud intends only to undermine a naturalline of thinking that may have seemed to establish that the content is true. He compares thiscontent to the central possibility specified in G. E. Moore’s paradoxical sentence, ‘I believe thatit is raining, and it is not raining’ (Moore 1951, 204). That sentence expresses a genuine logicalpossibility, but it is not a possibility Stroud says anyone ‘could consistently believe or assert tobe true’ (QR, 204).

5

See pp. 157–66.

6

Wittgenstein 1953; see in particular, §§ 28–35 and §§ 243–58.

Color, Error, and Explanatory Power 173


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attending to one’s own perceptions, but he finds them all lacking. A great dealwould be required, he argues, for one to be able to focus on one’s own perceptionsand identify the

color

properties involved. Stroud argues that the only way inwhich one could ever acquire conceptions of particular color properties is throughan initial process in which one believes that one is distinguishing among materialobjects according to the colors that those objects really have. And to believe that,one must believe that material objects have color.

Many of Stroud’s critics attempt to show how it is indeed possible to doprecisely what Stroud asks us to ‘try’ to do, i.e., ‘to start with no beliefs aboutthe colours of objects, make no use of any such beliefs anywhere, and . . . ascribeto [someone] perceptions of or beliefs about the colour of something’. MarkJohnston, for instance, agrees with Stroud that (in Johnston’s words):

. . . for ostensive definition to work there has to be considerable ‘stage-setting’. Thisrequires a background of belief and judgement about the kind of property beingdefined (or at least dispositions to so believe and judge.) Abstract away from that,and you

are

left with an ‘empty ritual’ of pointing to an item. No property isidentified. (2004, 192)

But, Johnston argues, this background need not include beliefs in which color isascribed to objects. Rather, certain ‘packages’ of the following four categories ofbeliefs and judgments would be sufficient:

(1) conceptions for each of the colors of what it would take for an arbitrarilychosen thing to have that color;

(2) a detailed set of beliefs about the qualitative similarities and differencesamong the shades that make the colors into a distinct family of properties;

(3) a rich set of beliefs about how the colors differ, for example, from thesmells and the sounds, and from the quantitative properties described ina mathematical physics;

(4) beliefs that connect various conditions of viewing with how things appearwith respect to color.

One can have beliefs of these four categories without believing that any objecthas color.

Johnston, however, does not elaborate upon how the ostensive definition mightproceed. I think Stroud is correct to question (in his reply to Johnston) preciselywhat the words that were ostensively defined in this way would come to mean.Stroud does not doubt that the words could come to have

some

meaning whendefined against a background consisting of the four categories of beliefs. WhatStroud questions is whether ‘the sense those words would have been given . . .would serve to express what we now express in sentences predicating color termsof physical objects. Would the thought and talk that remained be about

colors

aswe now understand them . . . ?’ (2004, 205.) For

that

– thought and talk about

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colors as we now understand them – is what the error theorist must be able toacknowledge and explain.

While Johnston does not explain his proposal in any more depth, he doesattempt to support it with something of a

reductio ad absurdum

.

7

If we

couldn’t

identify color properties against a background of these four categories of beliefalone, then Stroud would be correct to conclude that we could not identify colorproperties without believing that objects have color. But if we accept this conclu-sion, ‘we get the wrong interpretive results’ (2004, 193). If one needs to believethat objects have color in order to identify color properties, and thus in order tohave thoughts about color properties at all, then anyone who does not believe thatobjects have color, Johnston reasons, could not have thoughts about color prop-erties. However, if that were so, we would be forced to interpret philosophers suchas Galileo, who did not believe that objects have color, as not truly having hadthoughts about

color

, and thus as not having believed that objects do not havecolor. But the ‘authoritative interpreters’, Johnston argues, tell us that Galileoindeed believed this! So, we must be able to identify color properties against abackground of the four categories of beliefs.

The question, though, is whether it follows from Stroud’s claim that in orderto identify color properties we must believe objects have color that we mustinterpret Galileo as not having identified color properties (and thus as not havinghad thoughts about them). Stroud does not think it does, but Johnston does notaddress Stroud’s reasons for thinking this. Stroud is clear that what he claims notheorist could do is identify color properties and at the same time

consistently

deny that objects have color. Galileo identified color properties, Stroud thinks,and thus had thoughts about them, and he also claimed that objects do not havecolor. Stroud’s central claim is that doing all of this involves a substantial incon-sistency. The error theorist’s project cannot be consistently undertaken, Stroudthinks, even if its would-be conclusion – that people’s beliefs ascribing colors toobjects are all false – can be asserted.

8

Perhaps Johnston thinks there is somethingproblematic about Stroud’s emphasis on consistency, but if so he would need toaddress Stroud’s claims about it.

Alex Byrne also rejects Stroud’s claim that it is impossible to start with nocolor beliefs and then to identify a particular color property without adopting anycolor beliefs in the process. Byrne asks us to imagine a people who have neverseen ‘chromatic’ color before, only ‘achromatic’ color, and who thus have nobeliefs in which they ascribe chromatic color to objects. One day these peoplecome upon a stationary disc which is painted with an achromatic color pattern

7

See Johnston (2004, 193–7).

8

Stroud writes, ‘No one can consistently say “I am not now speaking”. But that doesnot mean that someone who says it is not really saying what he seems to be saying or that weare required to interpret him as not really saying it’ (2004, 208).



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and which has no chromatic color. However, the achromatic pattern is such thatwhen the disc is rotating (on a machine, say), the disc

appears

to the people tohave a chromatic color, a striking shade of blue. Byrne asks, ‘What’s to stop [thesepeople from] introducing a name for this shade and doubting whether anythingreally has it?’ (2002, 218). Byrne argues that if it were

we

(who do have colorbeliefs, he assumes) who came upon such a disc, we could easily introduce a namefor the color even if we did not believe that any object has it (say, if it were acolor we had never seen before, such as Hume’s missing shade of blue). But ifwe could do this, why could the imagined people not do it?

Byrne is certainly correct in supposing that, on Stroud’s view, we who do havecolor beliefs could in such a case introduce a name for the color even if we didnot believe that any object has it. Stroud does not deny that we can identify aparticular color without believing that anything in the world has

that particularcolor

. What is required for identifying a particular color, Stroud believes, is thatwe have beliefs in which we ascribe

some color or other

to objects. I suspect,though, that to Byrne’s proposal Stroud would respond that the imagined people

do

have color beliefs (as Stroud is understanding them), since they believe thatmaterial objects have

achromatic

color. If so, Byrne’s case would not be a casein which people identify a particular color property without believing that anyobject has color. Stroud does not say much about the distinction between chro-matic and achromatic colors, though, and perhaps Byrne would insist that heshould. Yet it is not clear how the distinction matters in the context of the argumentof Stroud’s in question, given that the error theorist claims that objects do nothave achromatic colors either. Lemons are not yellow, according to the errortheorist, but neither are clouds white nor elephants grey.

Contra

Byrne and Johnston, I’d like to grant Stroud that it

is

impossible ‘tostart with no beliefs about the colours of objects, make no use of any such beliefsanywhere, and . . . ascribe to [someone] perceptions of or beliefs about the colourof something’.

9

I grant this for the sake of argument. My question concernswhether that would truly show that an error theorist could not acknowledge all ofthe psychological facts he must acknowledge and at the same time consistentlymaintain that objects do not have color. That is not as clear as Stroud suggests.

If the error theorist cannot, on account of consistency, conclude that objectsdo not have color, it cannot simply be because he, in the past, believed in thatconclusion’s negation. We often give perfectly adequate explanations as to why

9

Paul Boghossian is another philosopher who rejects Stroud’s argument against theerror theorist by resisting the conclusion I shall here grant. Boghossian does not treat Stroud’sarguments for this conclusion in any detail, though. He says that they make a ‘complicatedappeal’ to Wittgenstein’s ‘private language argument’ and writes, ‘I don’t have the space to chaseall of Stroud’s optional assumptions in this argument, except to say that I have never seen aversion of the private language argument that makes it seem convincing; and Stroud doesn’tsucceed in changing my mind’. (2002, 237.)

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we

used to

believe a particular thing that now we regard as patently false. It seemsan error theorist could agree with Stroud that he needed

at some point

to believethat objects have color in order now to be able to understand others as havingbeliefs to that effect, but maintain consistently that he does not still, or now, havethose beliefs. He used the beliefs to get the understanding, as it were, but thenlater abandoned them, keeping only the understanding and concepts which thosebeliefs afforded him. An error theorist who argued in this way would admit thatany final conception of the world that held both that people have color beliefs andthat objects do not have color must also hold that the authors of that conception

used to

believe in the negation of that latter claim.It is true that when introducing his strategy, Stroud asks: ‘Is it a necessary

condition of our acknowledging the presence in the world of perceptions of andbeliefs about the colours of things that we

believe

that some objects are coloured?’(QR, 157 [my emphasis].) That is indeed an appropriate question to ask, in thesense that an affirmative answer to it might well remove the threat coming fromthe error theory. But the sorts of considerations Stroud delivers, even if all correct,would suggest an affirmative answer only to the following, importantly differentquestion: ‘Is it a necessary condition of our acknowledging the presence in theworld of perceptions of and beliefs about the colors of things that we

ever

believed

that some objects are colored?’ That an affirmative answer to this latter questionis the most Stroud in fact establishes can be seen, among other ways, by notingthe method he suggests we adopt in order to answer the (appropriate) questionthat he does ask. It is only a few sentences after asking the former question thatStroud writes, ‘Try to start with no beliefs about the colours of objects, make nouse of any such beliefs anywhere, and see if you could ascribe to anyone percep-tions of or beliefs about the colour of something’. All of Stroud’s attempts toanswer the former question consist in his arguing that one could not possibly dothat which he asks us to ‘try to’ do in this last quotation.

10

The essential question then is this: In order for one to acknowledge, at

timet

1

, the relevant psychological facts, does one need to believe

at t

1

that objects havecolor, or does one need only to

have believed at some time t

0

that they have color?That issue is not addressed at all in Stroud’s book, but I believe it is crucial.

Stroud’s (intended) argument might thus be expressed as follows:

(P): If one does not,

at t

1

, believe that objects have color, one cannot,

at t

1

,possess the capacity to acknowledge all of the psychological facts the errortheorist must acknowledge.

(C1): One cannot acknowledge all of the psychological facts the error theoristmust acknowledge and at the same time consistently maintain that objectsdo not have color.

10

See pp. 157–66.



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(C2): There remains no threat to the truth of our ordinary beliefs in the colorsof objects arising from the error theorist’s strategy.

I am granting that (C1) is available from (P), and that (C2) is available from (C1).However, as far as I can tell, Stroud’s arguments in service of (P) support onlythe (in one sense, weaker) premise:

(P*): If one has

never

believed that objects have color, one cannot possess thecapacity to acknowledge all of the psychological facts the error theoristmust acknowledge.

(P*) certainly does not imply (P). And Stroud gives no reason for thinking thatwe might in any way secure (P) by means of (P*). Reason would have to be givenperhaps for thinking that when possessing a particular capacity, one is, in somesignificant sense, ‘committed’ to all of those beliefs that one must have had inorder to have

attained

that capacity in the first place. The idea would be that, ifwe were so committed, then by truly abandoning any of those beliefs, we wouldthereby lose the capacity itself. But is there reason to think that when possessing(or even exercising) a particular capacity, one is committed in this way to all ofthose beliefs that one must have had in order to have attained that capacity in thefirst place? Stroud does not address this question.

Prima facie

, I think there is not. It is certainly not

always

the case that in orderto possess a particular capacity we need to believe every proposition we employedin acquiring the capacity. When I first learned how to ski, for instance, I learnedhow to stop. When I acquired the capacity to stop, I employed the belief thatthe best way to stop is to rotate both legs inward into the ‘snow plow’. Today, Ino longer believe that this is the best way to stop on skis; however, I can stillexercise, and thus still possess, the capacity to stop on skis by means of the snowplow.

11

Stroud might insist that there is an important difference between the skiingcase and the color case. In the color case, we

must

have color beliefs in order toacquire the capacity to identify color properties, he might urge, whereas in theskiing case, it is possible to acquire the capacity to stop by way of the snow plowwithout believing that this is the best way to stop. But even if this is true, wouldit matter? Why would we be more committed to beliefs that we

necessarily

employed than to those we employed merely contingently? In both cases (we areassuming), the belief in question is employed in the acquisition of the capacity.If consistency were an issue, it would presumably be an issue in both.

11

Perhaps I had seen more advanced skiers stop in a different way before I learned howto ski, in which case I may have believed only that snow plowing is the best way for

beginners

to stop, which is something I still believe. If so, we can easily imagine someone who learns tostop by way of the snow plow who has never seen anyone stop on skis in a different way.

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Of course, the skiing case is different from the color case, in which the capacityin question involves identifying something (color properties). But even with iden-tification, it is not always the case that in order to possess the capacity to identifysomething, we need still to possess every belief that we employed when acquiringthe capacity to identify it. When children first learn the word ‘unicorn’, for instance(and hence learn how to identify unicorns), they typically believe that unicornsdo exist (and not just in pictures). When they later learn that unicorns do not exist,they still retain the capacity to employ the word and to identify unicorns.

Stroud might protest that when we form the capacity to identify color proper-ties we

appeal to

or rely on the belief(s) in question in a way that we do not inthe unicorn case. Although children do typically believe unicorns exist when theyacquire the capacity to identify them, Stroud might say, the

reasoning

by whichthey acquire that capacity does not involve the proposition ‘Unicorns exist’. Theydo not appeal to the truth of this proposition in acquiring the capacity. Now, itis not clear whether Stroud even believes that when we acquire the capacity toidentify color properties we do appeal, in this sense, to propositions in which coloris ascribed to objects. Stroud says very little about the precise role he thinks colorbeliefs play in our acquisition of the capacity to identify color properties.

12

But ifhe does believe this, and if he is correct in doing so, it would still need to beexplained why we cannot possess a capacity without retaining every belief thatwe even relied on, or appealed to, in acquiring that capacity. What is the barrier?

13

So I do not think we should be persuaded by Stroud’s argument against theerror theorist. Stroud’s failure to establish (P) would not, however, diminish theimportance of one of the central lessons of his book: that there is a wide varietyof rich psychological facts that the error theorist would need to acknowledge andexplain in order to carry out his project successfully.

14

The fate of the error theoryturns on how well the error theorist can truly accomplish this while denying thatobjects have color. The sorts of psychological phenomena Stroud focuses on –those involving identifying and acquiring conceptions of color properties, for

12

I wish Stroud had been more forthcoming on this issue. What is it about possessingcolor beliefs that enables us to acquire the capacity to identify color properties? And, for thatmatter, how do we manage even to have color beliefs at all if it is so difficult to identify colorswhen in their presence? (The lessons about ostensive definition are supposed to apply no lessto material objects, like lemons, than to colorful patches in the mind.) I suspect that Stroud’sanswers to these questions would in some way appeal to his conviction that meaning and thoughtare grounded in social practices (Stroud, 1996). Stroud does not emphasize this view in his bookon color, but I do wonder to what extent his argument against the error theorist ultimatelydepends on it.

13

Johnston appears to raise the general point I have here made against Stroud, thoughhe does not develop it. See Johnston (2004, 195–6).

14

Byrne appears to concur. He thinks it is an ‘excellent point’ that the error theorist, asByrne says, ‘must find, somehow, a place in reality for our

perceptions

of color, for these arethe things that are supposed to be explained’ (2002, 217).



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instance – are typically paid little attention by error theorists, who often emphasizeother, related phenomena, such as the fact that objects appear to have color. I haveargued that Stroud has given us little reason to suppose that the error theoristcannot appropriately acknowledge all of the psychological facts that he must. Onequestion worth exploring, then, is whether the error theorist can satisfactorily

explain

them. Given the explanatory considerations upon which the error theorist’sproject is based, this question is crucial. Acknowledging that people have colorbeliefs while denying that objects have color is one thing;

explaining how

peoplehave color beliefs while denying that objects have color is another. I suspect thatdoing the latter is where the substantial difficulties lie.15*

References

Boghossian, P. A. 2002, ‘Seeking the Real’, Philosophical Studies 108, pp. 223–38.Boghossian, P. A. and Velleman, J. D. 1989, ‘Colour as a Secondary Quality’, Mind 98, pp. 81–103.Byrne, A. 2002, ‘Yes, Virginia, Lemons are Yellow’, Philosophical Studies 108, pp. 213–22.Clark, A. 2000, A Theory of Sentience, Oxford: Oxford University Press.Ellis, J. 2005, ‘Colour Irrealism and the Formation of Colour Concepts’, Australasian Journal of

Philosophy 83, pp. 53–73.Hardin, C. L. 1993, Color for Philosophers: Unweaving the Rainbow, expanded ed., Indianapolis,

IN: Hackett.Jackson, F. 1977, Perception: A Representative Theory, Cambridge: Cambridge University Press.Johnston, M. 2004, ‘Subjectivism and “Unmasking”’, Philosophy and Phenomenological Research

69, pp. 187–201.Mackie, J. L. 1976, Problems from Locke, Oxford: Clarendon Press.Maund, J. B. 1995, Colours: Their Nature and Representation, Cambridge: Cambridge University

Press.Moore, G. E. 1951, ‘Russell’s Theory of Descriptions’, in: P. A. Schlipp, ed., The Philosophy of

Bertrand Russell, New York: Tudor.Perkins, M. 1983, Sensing the World, Indianapolis, IN: Hackett.Stroud, B. 1996, ‘Mind, Meaning, and Practice’, in: H. Sluga and D. Stern, eds., The Cambridge

Companion to Wittgenstein, Cambridge: Cambridge University Press.Stroud, B. 2000, The Quest for Reality: Subjectivism and the Metaphysics of Colour, New York:

Oxford University Press.Stroud, B. 2002, ‘Explaining the Quest and Its Prospects: Reply to Boghossian and Byrne’, Philo-

sophical Studies 108, pp. 239–47.Stroud, B. 2004, ‘Unmasking and Dispositionalism: Reply to Mark Johnston’, Philosophy and

Phenomenological Research 69, pp. 202–12.Wittgenstein, L. 1953, Philosophical Investigations, translated by G. E. M. Anscombe, Oxford:

Blackwell.

15 I develop this suspicion at length in Ellis (2005). I argue that on no plausible accountof concept formation can the error theorist explain how we form color concepts (of the precisesort that the error theorist in particular must take us to have) without thereby rendering theseconcepts often applicable to material objects.

* Thanks to Jonathan Cohen, Bob Fogelin, Barbara Herman, Martin Jones, JohnMacFarlane, Alva Noë, Ric Otte, John Searle, Walter Sinnott-Armstrong, Barry Stroud, and thereferees of dialectica for helpful comments on drafts of this paper.

color, error, and explanatory power

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