Last modified: July 18, 2001
A number of authors have argued recently that the content of perceptual experience can, and even must, be characterized in conceptual terms.[2] Their claim, more precisely, is that every perceptual experience is such that, of necessity, its content is constituted entirely by concepts possessed by the subject having the experience. This is a surprising result. For it seems reasonable to think that a subject’s experiences could be richer and more fine-grained than his conceptual repertoire; that a subject might be able, for example, to discriminate in experience more shades of colors than he has color concepts. The key move in their argument, therefore, is to articulate the conceptual content of experience using demonstrative, instead of general, concepts. For instance, these authors argue that the content of my perceptual experience of a particular shade of green is properly characterized in terms of the concept expressed by the linguistic utterance “that shade” (said while pointing to the sample of the shade in question).[3] Even if I don’t possess a general concept for the shade I’m seeing – a concept of the kind typically expressed using color names like “chartreuse” or “lime” – nevertheless, these authors argue, the content of the experience can still be characterized conceptually using a demonstrative concept that I do possess.[4]
I’d like to argue against this position. In particular, the goal of this paper is to show that if you understand demonstrative concepts and their possession conditions in the way that these authors do, then demonstrative concepts cannot in general characterize the content of perceptual experience. At the center of the issue is a certain condition on demonstrative concept possession that is proposed by the authors whom I criticize. I argue, against these authors, that it is possible for us to make (or at least to imagine making) perceptual discriminations even in cases in which we fail to satisfy the proposed condition on possessing the demonstrative concepts that characterize the things discriminated. This follows from the fact that demonstrative-concept possession is, on the condition under consideration, cross-temporally demanding in a way that perceptual experience need not be. Further, I believe there is at least some reason (though not the reason articulated by the authors I consider) to think that the proposed condition on demonstrative-concept possession is a good one. If that’s right, then the position that I am criticizing does not just impose possession conditions that are inconsistent with its further claims about the nature of perceptual content. It in addition asserts that demonstrative concepts must be employed when, in fact, they may be unavailable. Without offering conclusive arguments, I will offer some reasons to think that those who have experiences with a certain content might lack even the demonstrative concepts that characterize it. Having articulated this hypothesis, I will explore some of its implications.
The paper comes in 5 parts. In §1 I present the view that demonstrative concepts characterize the content of perception, and I highlight the epistemological motivation that leads certain philosophers to hold this view. In §2 I discuss the possession conditions on demonstrative concepts. I argue for a condition of context-independence, which I call the re-identification condition, that can be stated in roughly this way. Possession of a demonstrative concept requires the subject to have the capacity to entertain a thought containing that concept independently of the context in which the concept originally had its application. I discuss two possible reasons for embracing this kind of context-independence as a condition on demonstrative-concept possession, one of which I am inclined to endorse.
In §3, however, I show that it is at best an
empirical question whether experiences satisfy the proposed condition of
context-independence. Because
demonstrative concepts do satisfy this condition, we can have, or at any rate
imagine having, perceptual experiences with distinct contents in cases in which
we do not satisfy the condition on possessing the demonstrative concepts for
the things discriminated. I conclude
that demonstrative concepts cannot in general characterize the content of
perceptual experiences. In §4, I
discuss possible responses to this argument.
Finally, in §5 I conclude with an analysis of the results, and suggest
some remaining problems.
Gareth Evans suggested, in The Varieties of Reference[5], that the content of perceptual experience is more fine-grained than the content of thought. “Do we really understand the proposal,” he wondered, “that we have as many colour concepts as there are shades of colour that we can sensibly discriminate?”[6] While we may understand this proposal, according to Evans, he believed that it was false. Evans believed, in other words, that we can sensibly discriminate more shades of color than simply those for which we have color concepts. But in thinking about the question Evans was concerned only with what might be called “general concepts” – concepts of the kind typically expressed using color names like “chartreuse” or “lime”. This limitation is important. If general concepts were the only relevant kind of concept to consider, then perhaps Evans’s point would hold.[7] But recently several authors have suggested that there’s another option afoot.
John McDowell and Bill Brewer point out that Evans failed to consider the possibility of using “demonstrative concepts” instead of general ones to characterize the content of perceptual experience. [8] Demonstrative concepts are those concepts that make use of a demonstrative expression to pick out the way the object or property now being experienced is given.[9] Demonstrative concepts, unlike general concepts, have the advantage of being “context-dependent”[10] – their semantic value changes depending upon the context in which they are applied. Since perception is obviously like this as well (the content of our perceptual experience changes depending upon the context in which it occurs), these demonstrative concepts are thought to be particularly suitable for characterizing the content of perceptual experiences.[11]
But demonstrative concepts, of course, are elements of thought – they figure in expressions that we can entertain in propositional attitude contexts, they are constituents of propositions that stand in inferential relations to one another, and so on (picking your favorite characterization of the semantic features of language or thought). This said, we might ask why anyone should be motivated to hold the view that perceptual content is characterized by something conceptual in the first place. There certainly doesn’t seem to be any obvious phenomenological reason to hold such a view. Indeed, those philosophers motivated by the phenomenology of perception clearly reject this idea. They typically think that the content of experience is in some way richer, more complicated, or more fine-grained than the content of thought, and therefore that perception ought not to be characterized in terms of the elements of thought at all. [12]
McDowell and Brewer are not motivated by the phenomenology of perception. Rather, they are motivated by a certain kind of epistemological concern. In particular, they’re motivated by the need to make sense of our capacity to have beliefs with empirical content, i.e., beliefs that are grounded in, or justified by experience. They believe that in order to make sense of this capacity, we must find perceptual content to be characterized in conceptual terms, since only conceptually articulated contents can justify one another. The argument for this position therefore has a classic transcendental form: Since a condition on the possibility of our having beliefs with empirical content is that perceptual experience have conceptual content, and since, ex hypothesi, we do have beliefs with empirical content, it follows that perceptual content must be conceptual. As McDowell says,
To avoid making it unintelligible how the deliverances of sensibility can stand in grounding relations to … judgements and beliefs … we must insist that …experiences … already have conceptual content.[13]
Now, I don’t intend to criticize this claim, or even to try to explain it here. I’m not sure I understand the argument for it myself.[14] But I do want to point out the very strong commitment that a position motivated by this kind of epistemological concern seems to take on. To defend the view stated above, one needs to argue not only that perceptual content is conceptual, but further that perceptual content must be conceptual (at least if we have beliefs with empirical content at all). The problem is that I don’t think McDowell or Brewer is successful in establishing this strong conclusion. Indeed, I believe that even the weaker conclusion, that perceptual content is conceptual, is suspect. The reason is that it’s possible to imagine[15], and we may even be capable of, making perceptual discriminations in cases in which we fail to satisfy the criteria on possessing demonstrative concepts for the things discriminated.[16] To see this we need to clarify the notion of “demonstrative concept” at issue, and especially to articulate the conditions under which a subject can be said to possess a demonstrative concept. I turn to these issues now.
2. Demonstrative concepts and context-independence: the re-identification condition
Let’s consider a
certain kind of context-independence requirement on demonstrative-concept
possession. The requirement, roughly
stated, is that possession of a
demonstrative concept requires the subject to have the capacity to entertain
that concept independently of the context in which it originally had its
application. Typically this means at
some later time. I will articulate this
general requirement more precisely by specifying the “re-identification
condition on demonstrative-concept possession”. The re-identification
condition states that in order to possess a demonstrative concept for x, a
subject must be able consistently to re-identify a given object or property as
falling under the concept if it does.
McDowell and Brewer both seem to endorse something very much like the
re-identification condition, and I am inclined to accept it as well. Our reasons, however, are quite
distinct. I begin with their
presentation of the issue.
McDowell and Brewer
both claim that in order to possess a demonstrative concept, a subject must
have a certain kind of “recognitional capacity” for the thing to which the
concept refers. This capacity ensures
that the demonstrative concept is a properly conceptual type of item. As
McDowell says,
In the presence of the
original sample, “that shade” can give expression to a concept of a shade; what
ensures that it is a concept … is that the associated capacity can persist into
the future, if only for a short time, and that, having persisted, it can be
used also in thoughts about what is by then the past, if only the recent
past. What is in play here is a
recognitional capacity, possibly quite short-lived, that sets in with
experience.[17]
And Brewer echoes this
sentiment when he says that the demonstrative concept of a color sample A “must
be a concept which can be employed to some extent, and however briefly, in the
absence of the sample A itself...”[18]
The motivation for
this requirement, according to McDowell and Brewer, follows from an intuition
about what it is for something to be a concept. They believe that in order for something to be a conceptual item
at all, there must be some kind of distance
between the thought had by means of the concept and the thing in the world that
makes the thought true. As Brewer says:
Part of what the
additional requirements [on demonstrative-concept possession] must achieve is a
certain distance between the subject’s conception of the relevant semantic
value and the mere obtaining of her confrontation with it which makes this way
of thinking of it available to her in the first place.[19]
And McDowell makes the
same point about the possession conditions for demonstrative concepts as
follows:
We need to be careful
about what sort of conceptual capacity this is. We had better not think it can be exercised only when the
instance that it is supposed to enable its possessor to embrace in thought is
available for use as a sample in giving linguistic expression to it. That would cast doubt on its being
recognizable as a conceptual capacity at all.[20]
The reason for this is
that
The putative thought …
is being construed so as to lack the distance from what would determine it to
be true that would be necessary for it to be recognizable as a thought at all.[21]
The point they want to
make, I believe, is that it doesn’t seem to make sense to think that a person
has genuinely entertained a thought
about x, if the so-called thought couldn’t be had independently of (i.e., at
some distance from) the presence of
x. A central source for this idea seems
to be the Wittgenstein of the Investigations,
who wonders about a person who says, “I know how tall I am” putting his hand on
top of his head to prove it.[22]
Now I’m genuinely
unsure whether this is a good motivation for the condition. The reason is that I’m not sure what the argument is that thoughts must be this
way. Why should we think that I can’t
have a thought about a color I’m now looking at just because I couldn’t later
recognize that color as the one I then saw?
Perhaps there is some idea that Evans’s Generality Constraint is at
play.[23] The Generality Constraint suggests that in
order to possess a concept a, a
subject ought to be able to predicate a of
lots of different things. But surely in
the case under consideration that constraint is satisfied, at least as long as
I’m looking at the color in question. I
can say, for instance, at least while looking at the color, that that color is darker than the color of a
macintosh apple, but lighter than the color of a rich red Burgundy wine. And it’s not clear to me from the
considerations adduced above why anything more is required to possess a
demonstrative concept for the color.
But even though I am not persuaded by the considerations that McDowell
and Brewer discuss, I do think that the recognitional capacity condition is
potentially plausible as a condition on demonstrative-concept possession. Let me say something about how I would
motivate it.
To pump up your intuitions, consider the following situation. A subject is presented with two visual stimuli – a triangle and a square. In response to the examiner's questions we find that the subject is able consistently to say that these are different shapes. The examiner asks, "Are these the same shape?" and the subject consistently answers, "No."
Now imagine that the same subject is given a new task. In this task the subject is presented with the same shape, a triangle, ten times in a row. Indeed, it is the very triangle that earlier was presented on the left.[24] We discover, to our amazement, however, that in response to the examiner's questions this time, the subject is unable consistently to classify this as the shape that was earlier presented on his left. Over the course of ten trials, in fact, 5 times the subject responds, "Yes, it’s the shape that was earlier presented on my left." and five times he responds, "No, it's not the shape that was earlier presented on my left".[25] Now, understand, I'm imagining a situation in which all the possible variables concerning perception are controlled for. The subject sees exactly the same thing ten times in a row, and 5 of those times he thinks it's the same thing he saw before, while 5 of those times he thinks it's not.
I want to suggest that if we were confronted with such a subject we'd have no choice but to think that he does not know what that shape on the left, the triangle, is. Perhaps we can imagine a variety of explanations for why he answers in the way that he does. For instance, we might hypothesize that he's looking for re-inforcement from the examiner, and that causes him to change his response. Or perhaps we could hypothesize that he's guessing randomly each time, so on average he gets it right on half the trials. Maybe we could even have a relatively sophisticated hypothesis according to which he thinks that what the shape is depends on how many times it’s been presented before. But whatever the explanation for his behavior, I think it is impossible for us to allow that such a person possesses the concept expressed by the phrase “that shape” (said while pointing to what is in fact a triangle). The reason for this, I think, is that one natural condition on the possession of a demonstrative concept is that a person be able consistently to re-identify a given object as falling under a given concept, assuming it does. Hence, the re-identification condition.
Let me be as clear as possible about how I understand the re-identification condition.[26] If a subject has a perceptual experience whose content is constituted in part by a demonstrative concept then she must, at that time, have an ability reliably to identify a separate experience as having the same content if it occurs after some interval (perhaps extremely short[27]) of no such experience. This condition is meant to hold, of course, so long as all other things are equal. I am assuming, in other words, that the ability reliably leads to success unless something happens that interferes – for instance, a distraction, the injection of a chemical that effects memory, the eruption of a malady now temporarily in remission, and so on. As long as none of these interfering conditions obtains, then the subject should be able reliably to manifest her ability. Notice, however, the requirement that the ability be reliable is not the requirement that it be infallible. On my interpretation of the condition it is necessary only that the subject be able consistently to re-identify, or that she have a reliable ability to do so. If her answers are at random, as they were in the motivating example above, then she will not have satisfied the condition; if her answers are perfect, then of course she will have. Somewhere in the gray area between – I know not where – we will stop saying she has satisfied the condition and start saying she has not. This, then, is the re-identification condition on demonstrative concept possession.
Now, we need to be a bit careful here. The re-identification condition may not be a condition on general concept possession for reasons that have been discussed extensively in the literature. In particular, if it is possible to possess a general concept in virtue of one’s capacity to defer to an expert user of terms that express that concept, then it will be possible to possess the concept without being able to satisfy the re-identification condition.[28] But this consideration isn’t relevant in the case of demonstrative concepts. The reason is that insofar as demonstrative concepts are demonstrative, no descriptive account of their content will characterize them completely. And in the case of deference it is precisely a descriptive characterization that’s at work. When Fred is said to possess the concept expressed by the word “arthritis”, despite the fact that he believes arthritis can afflict the thigh, it is only because in using the term he intends it to mean whatever it is that the experts mean when they use it. This is precisely the kind of descriptive characterization that will fail completely to characterize the content of a demonstrative utterance. So demonstrative concepts can’t be possessed by means of deference.
McDowell is clear about this when he requires that a condition on possessing a demonstrative concept for x is that you have (or at least that you have had) an actual perceptual relation to the thing to which the demonstrative concept refers. As he says,
Consider, for instance, someone who remembers the colour of a rose that she no longer has in view, and thinks, “I should like the walls of my room to be painted that shade”. The kind of thought I mean here needs to be distinguished from one that might be expressed by something like “I should like the walls of my room to be painted the shade of the rose that I saw on such-and-such an occasion”. One can have a thought of this second kind without remembering the shade itself, as we can naturally put it. Perhaps one remembers that it was a shade of pale apricot, and that it struck one as ideal for the walls of one’s room. In the case I mean, one has the shade itself in mind, as we can naturally put it: it does not figure in one’s thinking only as what fits some specification. [29]
And Brewer is even clearer about this when he says that demonstrative concepts are those concepts
grasp of which essentially depends upon the subject’s relations with the actual entities which constitute their semantic values.[30]
Therefore, it seems, all parties agree that if re-identification fails as a condition on demonstrative-concept possession, it won’t be because we can come to possess the demonstrative concepts in question by means of deference.[31] This clarification aside, I return to the re-identification condition itself.
I believe that the motivation articulated above provides us with good reason for thinking that re-identification is a condition on demonstrative-concept possession. It shows intuitively that if someone is incapable consistently of re-identifying a given object as falling under a given demonstrative concept when it does, then the subject fails a reasonable test for possession of the concept. Further, the re-identification condition I have motivated is precisely the same condition that McDowell and Brewer have in mind when they insist that a subject must have some “recognitional capacity” with respect to the thing thought about in order to possess a demonstrative concept for it. I have motivated the condition differently than they do, of course, but the condition suggested, I believe, is the same. Perhaps the difference in our motivations for the condition will turn out to be important, so let me be as clear about this as I can.
As we’ve seen, both McDowell
and Brewer are motivated by the intuition that thoughts in general, and hence
demonstrative thoughts in particular, are necessarily the kinds of things we
can entertain in diverse contexts. My motivation for the condition seems to
focus on something else. I’m interested
in the difference between being able to distinguish two things and being able
to have a genuine demonstrative thought about one of them. Our motivations, then, are almost the
converse of one another. Whereas they
want to insist that we need a certain distance
from the thing thought about in order for it to be a thought at all, I want to insist that we need a certain closeness to it in order for it to be a demonstrative thought. On my view the central feature of
demonstrative concepts is that they give us a relation to the very thing thought about, and not just to that thing
understood as distinct from some other things.
On their view the central feature of demonstrative concepts is that they
give us a certain relation to the
thing thought about, a relation that we can maintain independent of the actual
presence of the thing. Strangely, these
apparently converse motivations both point in the direction of the same
condition on demonstrative-concept possession.
In the next section I’d like to consider whether this is also a
reasonable condition on having a perceptual exerience. I believe it’s not.
3. Re-identification and perceptual experience
Suppose that the re-identification condition is a precise statement of the condition on demonstrative-concept possession that McDowell and Brewer have in mind. Then, in order to show that the content of every perceptual experience is conceptual, in the sense that it is constituted entirely by concepts, perhaps including demonstrative ones, that the subject possesses, they’ll have to show that we in fact make distinctions in experience only in circumstances in which we meet this condition on demonstrative-concept possession. And to show further that perceptual content must be conceptual, they’ll have to show that this empirical fact holds necessarily. I believe, however, that they don’t show the former and that they can’t show the latter. The result is that it’s at least conceivable that we make distinctions in experience in cases in which we don’t possess demonstrative concepts for the things distinguished. Therefore, demonstrative concepts can’t in general characterize the content of perceptual experience.
The empirical fact in question is whether having a perceptual experience of a given shade, for instance, ensures that the subject will later be capable of remembering the content of that experience in exactly the detail in which he originally entertained it. He must be capable of remembering, as McDowell puts it, “the shade itself.”[32] As it turns out, McDowell never provides us with any reason to believe that this empirical fact obtains. Instead, he “insists” that it must:
We can ensure that
what we have in view is genuinely recognizable as a conceptual capacity if we insist that the very same capacity to
embrace a colour in mind can in principle persist beyond the duration of the
experience itself.[33]
In a way, it is natural for McDowell to insist that perceptual experiences satisfy this constraint.[34] After all, on his view they must satisfy the constraint in order to be, as they are, the kind of thing that can ground beliefs and judgements. But surely it is an empirical question whether all experiences in fact have this feature. McDowell implicitly admits this when he allows that the recognitional capacity in question depends on a kind of perceptual memory, and that “obviously people differ in the retentiveness of their memory for precise shades”.[35] But having tied the recognitional capacity to one’s memory skills, it seems easy to imagine that someone might have no memory at all for this kind of thing. Here’s a plausible scenario.
Imagine a subject like the one above who’s in a similar situation. This time, however, the subject is being presented with simultaneously given color samples instead of shapes. In the first test we find that the subject is able consistently to distinguish two rather similar looking shades of green. That's to say, in answer to the question, "Are these shades the same?" the subject consistently answers no, and is consistently right to do so.
In the second test, however, the subject is presented ten times in a row with one of those two color chips. Now, I claim that it is perfectly conceivable that the subject might not be able to re-identify this shade consistently. That's to say, in response to the question, "Is this the color that was previously presented to you on your left?" the subject may answer five times yes and five times no. It’s perfectly conceivable, in other words, and there’s nothing about the nature of perception to keep it from being true, that our capacity to discriminate colors exceeds our capacity to re-identify the colors discriminated.
That the subject might not be able to re-identify her shade consistently seems to me not just conceivable but quite common.[36] Anyone who’s ever chosen paint for a room has probably had the experience. You look at two color chips, and conclude that one is better for the room than the other. Then you drop the chips accidentally. It can be very difficult to remember which one you earlier judged to be preferable. Although the difference between them was clear in your original experience of the color chips, the perceptual appreciation of this difference by itself doesn’t seem to ground a capacity for re-identification.
The claim, then, is roughly that the capacity to re-identify a very particular shade doesn’t seem to be a condition on experiencing it as such. We must be careful, however, about how we articulate this claim. It is no doubt true that there is some amount of time after which a given subject won’t be able to make the re-identification. Perhaps it’s five minutes, or perhaps it’s five days, but for all except those extraordinary subjects in possession of perfect photographic memories, there is some amount of time after which the task cannot be performed. This in itself is nothing exceptional, and indeed McDowell has admitted this much already by accepting that people’s memory skills can differ.
The point I want to make is really the converse of that one. My point is that for any given amount of time between the trials, we can imagine a subject who has a memory skill that doesn’t allow him to re-identify the sample after that amount of time. The reason for this is that there doesn’t seem to be anything about perception itself that places a lower limit on the amount of time over which we can retain our memory of the details of a given perceptual experience. To say this, though, is to say that perceptual experience, or at least the perceptual experience of colors, seems not to live up to the condition of re-identification.
But the upshot of this argument is devastating for McDowell and Brewer’s view. For notice that because of the first test we know that the subject is perfectly capable of distinguishing the two colors in question. To that extent we must say that the contents of the respective perceptual experiences of these colors are different.[37] But just because the subject is able sensibly to discriminate these colors doesn't mean that he possesses the demonstrative concepts for them, at least not if we accept (with McDowell and Brewer) that re-identification is a valid condition on demonstrative-concept possession.[38] Therefore, it looks as though we can make (or at least we can imagine making) discriminations in perception, and hence to entertain distinct perceptual contents, in cases in which we don’t satisfy the criteria for possessing the demonstrative concepts for the things discriminated. Demonstrative concepts, then, cannot in general characterize the content of perceptual experience.
4. Possible responses
I can imagine at least four possible responses to this argument that one could make on McDowell and Brewer’s behalf. To begin with, the argument depends on the idea that it makes sense to think of a subject who can make perceptual discriminations without having the relevant demonstrative concepts. So the first possible response is just to deny that such a person could exist. One might deny, in other words, that there could be a subject capable of discriminating two shades consistently, but incapable of re-identifying the shades. This strategy would amount to denying the possibility of the alleged counterexamples to the view.
The problem with this strategy is that it doesn’t look like there’s any principled way of endorsing the denial. Once we’ve admitted that the recognitional capacity depends upon the subject’s memory, it’s hard to see how we could then go on to say that in principle everyone who has experiences also has a certain capacity to remember them. There doesn’t seem to be anything about experiences per se that requires us to be able to remember them later in exactly the detail in which we originally experienced them.[39] So it looks to me like it must be an empirical question whether there are people with no memory for shades as perceived. But if the connection between perception and memory is an empirical rather than an a priori issue, then the claim that demonstrative concepts characterize perceptual content, even if it turns out to be true, will be contingently instead of necessarily so. And that wouldn’t be sufficient to sustain the epistemological motivation that got the project started.
A second strategy is to accept that such a person could exist, but deny that in the example in question he is having experiences of the two shades. The idea might be that these are not really experiences, since they’re not the kinds of things that are in principle available to be taken up by our cognitive systems (they’re not available to spontaneity, to use the Kantian terminology).
The problem with this strategy is that at least at first blush it seems as though these are canonical kinds of experiences. After all, surely the discriminatory capacity involved in making these kinds of distinctions is a capacity of experience. What else? So to argue that the subject in question isn’t having genuine experiences seems like just a trick to define away all the interesting potential counterexamples to the view. On such a view it becomes trivially true that experience is conceptual, since any experience alleged to have a content that is not characterizable in conceptual terms is, in virtue of this fact, not an experience. But surely the claim that perceptual content is conceptual was not meant to be true by definition! So to make this idea stick one needs to give a more substantive defense of the claim that we shouldn’t count these as experiences. I don’t see an obvious way to defend this claim.
A third possibility is to deny that re-identification is really the condition on demonstrative-concept possession that McDowell and Brewer had in mind. I can’t find any textual support, though, for a view like this. I admit that I am motivated to embrace the condition for a very different reason than McDowell and Brewer are, and it is puzzling that two such different ways of thinking about demonstrative concepts should lead to the same condition on possessing them. But it seems to me that the re-identification condition and the recognitional capacity condition are just two different names for the same thing. Under the heading of “re-identification condition” we understand the capacity to re-identify a given object as falling under a given demonstrative concept if it does. Under the heading of “recognitional capacity” we understand the capacity to recognize, on different occasions, the thing to which the demonstrative concept refers. I don’t see that there’s any room for a distinction between these two ways of thinking about what it takes to possess a demonstrative concept.
A final possibility is
potentially more troubling. The
strategy behind this approach is to accept re-identification as a condition on
demonstrative-concept possession, but reject the analysis suggested of the
content of the subject’s experience.[40] On the new analysis, the content of the
experience is articulated in terms of a demonstrative concept that the subject
possesses, but it’s a different demonstrative concept than the one I say he
lacks. Consider again the case of the
two color samples that the subject is capable of distinguishing. One might argue that in this case the
subject doesn’t have two experiences which, in comparing them, he comes to
recognize are different. Rather, he has
one experience the content of which is that
there is that difference between the two samples. Since my argument depends on there being two perceptual contents
where there is only one demonstrative concept,[41]
this analysis of the situation would pose a problem for my view.
I admit that I’m not
entirely sure how to respond to this way of resisting my argument. But I think there are at least two potential
problems with it. First, I’m not sure
how one could argue that this is really the right analysis of the
situation. What kind of argument does
one bring to bear in order to show that this is a single experience of
difference instead of two different experiences? There must be a good answer to this question, but I don’t think
the current literature on perceptual content allows us to answer it with any
certainty.[42] Of course, having allowed for the
possibility of the alternative analysis, the inability to defend one over the
other becomes a problem for my view as well.
But even if one had good reason for thinking that this is a case of the
perception of difference instead of a case of different perceptions, it still
seems that the suggestion needs to be worked out more completely. After all, not all experiences of difference
are the same, and what needs to be characterized is this very experience of difference between those shades. A more
complicated version of my argument, then, would have to try to show that we can
perceive differences between color pair
differences, even in cases in which we can’t re-identify the color pair
differences involved. Or at least it
would have to show that we can conceive of someone with this combination of
abilities and disabilities. I suspect
that we can, but I don’t think the details are worth pursuing here.[43]
5.
Conclusion
I
have argued that we can make, or at least imagine making, distinctions in
perception in cases in which we don’t possess demonstrative concepts for the
things distinguished. If that’s right,
then it’s wrong to suggest that to each distinctive perceptual experience there
corresponds a distinctive content characterized by a demonstrative concept
possessed by the subject. The problem with this proposal can be put in a perspicuous,
though slightly misleading, way. In
order to make sense of the idea that demonstrative concepts characterize the
content of perceptual experience, we need to put apparently competing demands
on the notion of a demonstrative concept.
On the one hand, a demonstrative concept, insofar as it is demonstrative, has to be
“context-dependent”. That’s to say, the ability to grasp the concept
“essentially depends upon the subject’s relations with the actual entities
which constitute their semantic values”.[44] On the other hand, a demonstrative concept,
insofar as it is a concept, has to be
context-independent, in the sense that the subject needs to be able to
entertain the concept independently of the context in which it has its
principle application. The question is
how a subject could come to possess such a demonstrative concept if to do so
requires both that the subject have a relation with the sample involved and
also not have such a relation. This
looks like an inconsistent demand.
In fact, things are not quite as bad
as I just made them out to be. The
requirements for context-dependence and context-independence aren’t, strictly
speaking, in conflict with one another.
After all, at least on a certain kind of reading, the context-dependence
requirement simply says that in order to have a demonstrative concept of a
shade, one must have, or at least have
had, some perceptual relation to the shade in question. In other words, although Brewer speaks in
the present tense of the “subject’s relations with the actual entities”, I
think what he must mean by this is the relations that the subject has had, at
one time or another, with those entities.
On the other hand, the context-independence requirement simply says that
in order for the demonstrative concept of a shade to be a concept, one needs to
be able to entertain it while not in the perceptual presence of the sample. Strictly speaking, there’s no conflict.
But
even if there’s no actual conflict between these requirements, once we recall
the motivation for them the problem will become clear. Recall that one important reason for
emphasizing the context-dependence of demonstrative concepts is that this makes
them look like the kinds of things that are appropriate for characterizing
perceptual content. But perceptual
experiences are, at least potentially, dependent on their context in a stronger
way than demonstrative concepts are. To
the extent that demonstrative concepts are the kinds of things capable of
characterizing perceptual contents, they must be dependent on their context in
this stronger way as well. The
difference is that in the case of perceptual experiences it’s not clear that
having seen a shade, at some time in the past, is sufficient to guarantee that
the subject could later, in the absence of the sample, entertain the content of
the experience he originally had. As
we’ve seen, it’s an empirical question whether perception actually works this
way. If it turns out to be false that
experience (and therefore the demonstrative concept that characterizes it) has
this feature, then the context-dependence requirement is genuinely in conflict
with the context independence requirement.
And even if it turns out to be true that experience (and therefore the
demonstrative concept that characterizes it) has this feature, it’s still only
a contingent fact about our perceptual capacities. That’s not enough to show, as McDowell and Brewer hope to, that
experience must be conceptual.
One
enticing option for McDowell and Brewer, given their motivation for the
re-identification condition, may be to re-evaluate its plausibility. From their point of view the condition may
seem, upon further reflection, to be too strong anyway. [45] Recall that their goal is to be able to make
sense of our capacity to have thoughts on the basis of perceptual
experience. Considering only this
issue, it may seem that I am perfectly capable of having a thought about a
shade I am currently perceiving even if I’m not capable, at some later time, of
entertaining the content of the thought I then had. The reason they denied this initially is because they believed
that there must be some distance between
the thought had by means of a concept and the thing in the world that makes the
thought true. But the argument for
this claim seemed pretty thin – at least it did to me – so perhaps there is
room for backing out of it. The strategy for McDowell and Brewer, then, would
be to find some weaker requirement on demonstrative-concept possession, a
requirement that experience could live up to as well. If they could find such a requirement, then at least they would
be able to beat the charge that their view is internally inconsistent.
The
problem for this tactic, as I hope I’ve shown, is that there seems to be a
different kind of intuitive motivation for the very same condition. In order to back off of the
re-identification condition in a full-fledged way, therefore, McDowell and
Brewer will have to show why the example I gave in §2 doesn’t plausibly
motivate it either. It’s certainly
conceivable that they can show this, but I myself can’t see how the argument
will go. Absent an argument against the
re-identification condition for demonstrative concept possession, it seems to
me that there is no hope for the McDowell/Brewer claim that the content of any
perceptual experience can be articulated using demonstrative concepts possessed
by the subject of the experience.
In the meantime, however, I
take myself to have a serious problem to contend with as well. For if I’m right that perceptual experience
can’t in general be characterized by demonstrative concepts, then how are we to
make sense of the fact that we are nevertheless capable of having thoughts on
the basis of experience? This is a big
question, that goes well beyond the scope of this paper. But I do see at least two apparently
relevant possibilities in the area, both of which are anathema to the
McDowell/Brewer point of view. In the
first place, it may be that there are two different kinds of experience – those
with conceptual contents and those with non-conceptual contents. McDowell and Brewer cannot abide this
suggestion because for them experience is in its nature reason-giving, so the
idea of an experience with a non-conceptual (and therefore non reason-giving)
content is an oxymoron. But if what
I’ve been arguing is right, then it certainly seems as though we can imagine
perceptual experiences that make discriminations for which we don’t possess the
relevant demonstrative concept. All
else being equal, then, it seems reasonable to think that these experiences
have genuinely non-conceptual contents.
A further question is
whether these non-conceptual contents can themselves serve as the basis for
thought. One possibility in this area,
also in tension with the McDowell/Brewer approach, is that experience serves as
the basis for thought in some way other than by standing in justificatory or
reason-given relations to it. If this
is a genuine possibility, then perhaps even experiences with non-conceptual
contents could in some way or another serve as the basis for thought. I confess that at the moment I have no idea
what such a non-justificatory relation could be. Even so, both of these seem live possibilities to consider in
this area, possibilities that are effectively squelched by the pre-suppositions
of the McDowell/Brewer approach.
Needless to say, there may be others as well. In any event, I believe that the epistemological concerns to
which these possibilities speak are genuine and pressing. But whatever the answer to the
epistemological question is, I take the results of this paper to show that it
must be formulated with respect for the phenomenology of the underlying
perceptual experiences.
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[1] Some or all of the material in this paper was presented to audiences at Stanford, Berkeley, Birkbeck, Princeton, and the International Society for Phenomenological Study at Asilomar. I am grateful to all of these audiences for the opportunity to present the material and for helpful comments on it. I have also had fruitful discussions about this material with and/or comments on it from Bill Brewer, Liz Camp, Cheryl Chen, Paul Coppock, Hubert Dreyfus, Eddie Cushman, Gil Harman, Mark Johnston, Alva Nöe, Mark Okrent, Christopher Peacocke, Philip Pettit, John Searle, Roger Shepard, Scott Soames, Dmitri Tymoczko, and two anonymous reviewers. I would like to thank Bill Brewer in particular for a series of very fruitful and informative e-mails on the topic. I hope and expect that my criticisms of his and McDowell’s views will be taken in the constructive vein in which they are intended. Financial support for this research was provided in part by the James S. McDonnell Project in Philosophy and the Neurosciences and by Princeton University through a Supplemental Support Award for Honorific Fellowship Recipients. I would like to thank both of these institutions. Finally, as always, I’m especially grateful for help and support from Cheryl Chen.
[2] To say that the content of the experience is characterized in conceptual terms is to say that the content of the experience is constituted entirely by concepts possessed by the subject of the experience. These concepts precisely capture, therefore, both the substance of, and the level of detail in, the experience. The principle proponent of this view is John McDowell. He first articulates the position explicitly in McDowell 1994, especially Lecture III and Afterword Part II. (Unqualified references in the text and footnotes will be to this work.) He defends the view further in McDowell 1998, where he takes on some criticisms leveled by Christopher Peacocke in Peacocke 1998. (I have criticized Peacocke’s view, and offered a different analysis of the issues, in Kelly 2001; Peacocke has responded to this criticism in Peacocke 2001.) Bill Brewer argues for a position very similar to McDowell’s in his recent book Brewer 1999, especially in chapter 5. And a related view is defended in Sedivy 1996. As we will see, a central issue in McDowell’s presentation of the view has to do with the connection between perception and memory. Other relevant discussions of this relation occur in Martin 1992, Raffman 1995, and Jolley and Watkins 1998. The general issue also seems to be discussed in Heck 2000 which, unfortunately, appeared too late for me to be able to take it into account in this paper.
[3] The demonstrative concept is something of a chimera: it has the body of a singular term but the head of a general concept. In many ways it acts more like a singular term than a general concept, however, since it applies to only one entity and that entity actually constitutes its semantic value. (See Brewer 1999, p. 171.) The point of adding the concept to the bare demonstrative is to distinguish between intended referents in cases where the demonstrative alone cannot. For instance, the utterances “that shade” and “that shape,” both said while pointing to the very same object, have different referents, and it is the general concepts adjoined to the bare demonstrative that make this clear.
Knowing that “that shade” has a different referent than “that shape,” however, still doesn’t tell us what the referent is. This is because a demonstrative utterance like “that shade” is ambiguous between the shade that is experienced and the shade as the subject experiences it (at the time of the utterance). We might call this latter the shade as experienced. It is what Peacocke calls the perceptual manner of presentation of the shade (see Peacocke 1989). We can imagine the shade that is experienced remaining the same while the experience of it changes. For instance, we can imagine a fog gradually dissipating around a color chip. In such a case my experience of the color may become progressively clearer while the color I’m experiencing remains constant. (Thanks to Mark Johnston for this example.) If the demonstrative concept is to have any hope at all of characterizing the content of the experience, it must pick out different referents as the fog clears. But it cannot do that if the content of the demonstrative concept is individuated by the shade that is experienced. It’s possible to hold the view, of course, that demonstrative thoughts are individuated by the object in the world that they pick out (see, for instance, Kaplan 1989). If this view is right, then McDowell and Brewer are wrong for trivial reasons. For the purposes of this paper, then, I will assume that the demonstrative concept refers to the shade as experienced. McDowell clarifies his position on this issue in response to a criticism by Peacocke that highlights these difficulties. See McDowell 1998 and Peacocke 1998.
[4] For the purposes of this paper I will assume, as McDowell does explicitly, that the content of an experience is only properly characterized using resources at the disposal of the subject having the experience. For McDowell’s discussion of this see especially pp. 164 ff. It is of course possible to argue for the viability of a third-person characterization of perceptual content, perhaps by extending a kind of Davidsonian understanding of mental content to the realm of perception. I won’t, however, consider this issue further here.
[5] Evans 1982
[6] ibid., p. 229. As McDowell remarks (see McDowell 1994, p. 56 footnote 11) the point is not meant to be restricted to the case of color.
[7] I say “perhaps” because there is still some work to be done in characterizing the possession conditions for general concepts. Until we know what these conditions are, we won’t know in what sense the subject can be said to make more perceptual discriminations than just those for which he possesses general concepts. As we’ll see, McDowell and Brewer both recognize the need to rise to this challenge in the case of demonstrative concepts – that’s why they both attempt to specify (at least some of) the possession conditions for demonstrative concepts. But once we have these conditions in place we can ask explicitly whether every distinct perceptual content must, qua perceptual content, satisfy them. I will argue that they need not.
[8] The central passages are in Brewer 1999, pp. 170-174 and McDowell 1994, pp. 56-60, 170-174.
[9] Paul Coppock has pointed out to me that McDowell himself never uses the phrase “demonstrative concept”. But Christopher Peacocke uses the phrase in characterizing McDowell’s view and McDowell doesn’t complain about this characterization (see Peacocke 1998 and McDowell 1998). Likewise Brewer, in articulating a view that is meant to be “an extended development of what [McDowell] says [in Mind and World]” (Brewer 1999, p. 149) uses the phrase as well. I can’t see any harm in it.
[10] See for instance Brewer 1999, p. 171.
[11] It’s important to re-emphasize here that the demonstrative concepts that will do the trick are those that are individuated not by the object or property that is experienced, but by the object or property as experienced. See footnote 3.
[12] Naturally enough, writers in the phenomenological tradition are the ones who most clearly exemplify this attitude. See, for instance, Heidegger 1962; Heidegger 1988; Heidegger 1995; Husserl 1973; Husserl 1997; Merleau-Ponty 1962. But I take it that Evans is motivated, at least sometimes, by this concern as well.
[13] McDowell 1994, p. 46.
[14] For some interesting ideas about how to understand this argument and what its strengths and weaknesses are, see the work done by Cheryl Chen in her UC Berkeley dissertation.
[15] I am assuming here that if we can imagine such a situation then it’s possible; that conceivability, in other words, entails possibility. Whether this is true in the general case is something I have no opinion about. But when dealing with cases concerning perceptual discrimination, I think it is reasonable to suppose that there is a rather tight connection between what we can imagine and what is possible. Thanks to an anonymous editor for pushing me to make this clarification.
[16] I will assume that if a subject can discriminate perceptually between two stimuli A and B, then there is some distinction between the content of the subject’s experience of A and the content of his experience of B. This distinction may not itself be easily accessible to the subject, as in the case of the alleged chicken sexers who can distinguish male from female chicks but nevertheless claim that the chicks look alike even to them. But barring magic, I think, there must be some distinction between the experiences, no matter what the chicken sexers say. Otherwise how can we explain their actions? There is, of course, a complicated general question about the relation between the content of an experience and what the experience is like for the subject. I do not intend to address this general question here. I will say, however, that I am inclined to agree with Husserl, and the phenomenological tradition that follows him, that whatever the relation it is not straightforward. In particular, the content of an experience can often exceed what a naďve subject takes the experience to be like. Phenomenology is a difficult art that must be learned. But there are limits, too. If a putative feature of experience is in principle inaccessible to the subject of the experience, then I don’t see how it can be considered part of the content of the experience. It is the subject’s experience, after all, so if he cannot even in principle lay claim to a given feature of it, then that feature must be ruled out of court. Thanks, again, to an anonymous editor for pushing me to this clarification.
[17] ibid., p. 57.
[18]Brewer 1999, p. 175.
[19] ibid.
[20] McDowell 1994.
[21] ibid.
[22] See Wittgenstein 1958, §279. McDowell refers to this passage on p. 57.
[23] See Evans 1982, esp. pp. 100-105. The Generality Constraint follows from the observation that thoughts are structured. As Evans says, “If we hold that the subject’s understanding of ‘Fa’ and his understanding of ‘Gb’ are structured, we are committed to the view that the subject will also be able to understand the sentences ‘Fb’ and ‘Ga’.” (p. 101).
[24] To make this as similar as possible to the recognitional capacity situation, we can even imagine that directly before each trial the subject is presented with the pair of shapes, triangle on the left.
[25] Gil Harman has pointed out to me that this test won’t tell us anything if we don’t already know that the subject can distinguish right from left. We’d have to establish this beforehand.
[26] And let me also insist that as far as I can tell this is the way McDowell and Brewer understand the requirement as well. As an anonymous editor has pointed out to me, however, McDowell does seem to equivocate. See footnote 34. The clarification of the condition in this paragraph also owes its formulation in part to an anonymous editor.
[27] How short? Well, it has to be long enough that the interval counts as a break in the original experience, so it can’t be indefinitely short. The interval, in other words, has to be long enough to be experienced itself. But other than this, as short as you like.
[28] I’m thinking, of course, of views concerning general concept possession like those presented in Burge 1979. Something similar to the notion of deference that’s at work in these views is also utilized, though in a slightly different context, by advocates of the Causal Theory of Names.
[29] Ibid., p.
172, my italics.
[30] Brewer 1999,p. 171, my italics.
[31] This is true at least about the demonstrative concepts we’re considering here – those for which the content is individuated by the shade as perceived, not the shade that is perceived. If the content of a demonstrative concept is individuated by its referent, of course, then it will be possible to possess the concept by means of deference. But in this case demonstrative concepts will clearly fail to characterize perceptual contents anyway. See footnote 3.
[32] By which he means, as I have already said, the shade itself as it was originally experienced. Recall that because this is a demonstrative concept – because the shade itself (as it was perceived) figures in the content of the experience - nothing less than the exact shade (as originally experienced) will do.
[33] McDowell 1994, p. 57, my italics. McDowell is insisting, in other words, that the condition on something’s being a conceptual capacity is always in principle met whenever the person is having a perceptual experience.
[34] As an anonymous editor has pointed out to me, it is unclear from this passage exactly what the constraint is. McDowell says here only that the capacity to embrace the color in mind can persist, but the discussion of the distance requirement on demonstrative concept possession in §2 suggests that he means further that the capacity does persist and so can be exercised. If the capacity to embrace the color in mind can persist in the absence of the color, but in fact it doesn’t, then it’s not clear in what sense the required distance from the sample has been achieved. Moreover, it’s not clear to me what a capacity would be that can in principle persist but in fact never does. There is some evidence that McDowell means the capacity does persist. For instance, he says that “We had better not think [the capacity to express a demonstrative concept exactly as fine grained as the experience] can be exercised only when the instance … is available for use as a sample” (p. 57). If this is what we had better not think, then what we’d better think is that the capacity to express this demonstrative concept can be exercised in the absence of the sample. If we can exercise this capacity in the absence of a sample, then the capacity does persist and can therefore be exercised, which is stronger than saying merely that it can persist.
[35] Ibid.
[36] Thanks to an anonymous referee for encouraging me to emphasize this point, and for providing the example.
[37] This is one possible place to resist my argument against McDowell and Brewer. See the final possible response in §5.
[38] Notice that the subject doesn’t possess the demonstrative concept for the shade at any time, even when in the presence of the shade. The whole point of the re-identification condition is that possession of the demonstrative concept in the presence of the sample is dependent on whether or not the subject, in virtue of her experience of the shade, thereby has the capacity to entertain the demonstrative concept in its absence. Thanks to an anonymous referee for emphasizing this point.
[39] Perhaps there really is a connection between perception and memory, and a conceptual connection to boot. What this connection is, however, needs to be explicated carefully. An anonymous editor has suggested to me that Oliver Sacks’ case of “Jimmy” pushes one to think that without the capacity to remember experiences, it’s questionable whether they should count as experiences at all. Even if this is correct, and it may be, I don’t believe it provides the connection between perception and memory that McDowell needs. Remember, McDowell needs the subject not just to be able to remember that he’s had the experience of a certain shade, for instance, or even to be able to remember it well. McDowell needs the subject to be able to remember the precise shade, the shade itself – the shade, in other words, in exactly the substance and detail in which he originally experienced it. It is far from obvious to me why this connection between perception and memory should obtain. Anyhow, if it does obtain it will have to be argued for instead of merely “insisted” upon.
[40] I owe this suggestion to Mark Okrent.
[41] In other words, my argument depends on there being a distinction between the content of my experience of the color on the left and the content of my experience of the color on the right (two perceptual contents) and also that in re-identifying them I fail to make that distinction (one demonstrative concept). Better: insofar as I have the demonstrative concept “that shade,” it is not fine-grained enough to distinguish between the two colors which, in my experience of them, are distinct.
[42] Because of the difficulty in determining how to count the number of experiences had, my anonymous referee suggests a different way of formulating the problem. I will paraphrase the referee’s comments very closely. The issue is, on this formulation, whether the content of one’s perceptual experience at a time is partly determined by the content that characterizes the experience one has of the color of each of the color chips. The response being considered has it that the content of the experience is not so determined: it involves only the content that the chips are different colors (though it could also, presumably, involve some content concerning the general colors of the chips, e.g., that they’re both green). The referee suggests that on this formulation the offered response is “most implausible.” I think this is probably a better way of formulating the problem. Unfortunately, I don’t see why it is obvious on this reformulation that my opponent is wrong. The question still remains whether the experience that the colors are different necessarily has as part of its content the representation of each of the colors themselves. I’m just not sure how to answer a question like that, and failing an answer to that question the offered response remains in play.
[43] In fact, this isn’t really enough either, since it could be argued that even in this new case we have a single perception of difference between color differences, instead of two different experiences of distinct differences between colors. The problem simply re-iterates itself. Probably the best tactic is to try to show that you couldn’t have an experience of that difference between those colors without also having an experience of those colors as distinct. But how to show this I have no idea.
[44] Brewer 1999, p. 171.
[45] I owe this observation to Paul Coppock.