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Phenomena and representation.


1.1 When it comes to the role of phenomenal states in perception, there are three major positions that might be held(1): (i) Phenomena have properties, and we 'read off' these given properties in making perceptual judgements that ascribe properties to the world. This view holds that perception is itself noncognitive experience of phenomena and the first post-perceptual act is a cognitive one involving the perceiver's 'reading off' from the phenomenal properties. I will call this position the '"read-off" position'. (ii) Phenomena are not 'read off'. They are noncognitive causes of perception, which itself is primarily a certain sort of cognitive state. Phenomenal states are not themselves perceptions, nor even necessary to perception, but, at least sometimes, play an integral, causal role in perception, and so cannot be completely discounted in explaining perception itself. I will call this positio the 'causal position'. (iii) Phenomena are mere epiphenomena of perceptual processes. While phenomena may not be epiphenomena altogether (for instance, they may be causes of thoughts about themselves), they play no 'read-off' or causal role in perception itself, which can be described and explained without reference to phenomena. Like the causal position, this view understands perception as a cognitive, information-processing state of an appropriate kind. I will call this view the 'epiphenomenal position'.

In its most extreme form, the 'read-off' position holds that perception has bot an inner component and an outer component, the inner component being a representation of the outer. This inner component, which is something like a photograph or portrait (however distorted), is a phenomenon, accessible only to the person whose phenomenon it is. Phenomena have properties such as colour and shape; and it is because of the projective nature of these inner properties tha phenomena represent the outer world to us, bringing us to believe that like properties exist out there, as well as in us. To distinguish the ways in which properties such as colour or shape are instantiated or else to distinguish the kinds of things which possess the properties, the inner instance of the propert is called a phenomenal property: the outer, a real or external property. Becaus red exists phenomenally, we ascribe red to objects out in the world; and becaus square exists phenomenally, we ascribe square to objects in the world. We name our phenomenal colour 'red' and that gives us the name of the colour also in so far as we believe it to be instantiated in the world. The same for 'square.' I will call this version of the 'read-off' position the 'Phenomenological View'.(2)

This view has often come under attack. Philosophers influenced by Roderick Chisholm's [1957] Adverbial View have argued that there are no phenomena as objects; there are only phenomenal states. And if there are no phenomena as objects, there are no phenomena having properties such as colour or shape. Colour and shape, it is concluded, are properties only of real objects.

The Adverbial View is well motivated; however, it is not clear that all Adverbialists actually reject the 'read-off' position. Some seem to believe tha we do 'read off' from our phenomenal states to our perceptual judgements (from 'perceiving redly' to 'There's a red object that I am seeing'). My aim is to argue against any version of the 'read-off' position. I will not give knockdown arguments against the view (I suspect that 'knockdown' arguments are generally impossible in theoretical matters), but I hope to eviscerate the position enoug so that readers will no longer feel compelled by some version of it and will come to see the other positions as genuine--even more reasonable--alternatives. I will focus my arguments on the Phenomenological View. Although it is an extreme version of the 'read-off' view, nevertheless, seeing its weaknesses, an the ways in which it is weak, will enable us to see the weaknesses in any 'read-off' position, including the less extreme ones. Like Berkeley, I will defend the proposition that phenomena and external objects do not have similar properties. But unlike Berkeley [1713/1965, 146-8 and 159-60], and like the Adverbialist, I will argue that colours and shapes, and so forth, if properties of anything at all, are properties of external objects, not phenomena.(3) If phenomena have no colours or shapes, then it cannot be true that we name phenomenal colour or shape first, or that phenomenal properties are our first instances of colour or shape.(4)

One thing that is very important to see right at the outset is that introspection cannot settle the issue of which of the three positions is correct. One compelling piece of evidence for this claim is that there are many defenders of each of the views. Moreover it is difficult to imagine how we coul tell, from looking inside ourselves, what role is being played by the phenomena we are experiencing. So, if we want to settle the issue, we will have to give other sorts of reasons.(5)

1.2 Why does the Phenomenological View hold that phenomena are themselves coloured, have shape, and so forth? It is certainly not necessary for something to be a successful representation of red that it be red (this just-written word 'red', for instance), or even have a colour (the same word spoken aloud, say). One reason for the belief, as I will discuss later on, is that generally when one perceives red things one experiences similar sorts of phenomena in each case. And since these sorts of phenomena usually accompany the perception of th colour red, it is natural to call the phenomena 'red' also.(6) But, among philosophers and psychologists, there is a deeper reason behind this belief as well: 'If our phenomena do not have colour or shape, how did we ever get such concepts?' I cannot pretend to answer that question, at least not in this paper but what I can show is that the Phenomenological View is also unable to provide an answer to the question. If phenomena were like photographs, perhaps the Phenomenological View could provide an answer. But phenomena are not like photographs--or so I will argue.

In simple outline, my initial arguments will be that different phenomena can represent the same colour or shape, even the same colour-token or shape-token, and that each member of a set of similar sorts of phenomena can represent different properties. When I establish these claims, it will be fairly compelling to draw the conclusion that phenomena have neither colours nor shapes. And once we draw that conclusion, the plausibility of any 'read-off' position will be greatly weakened.


2.1 This section will deal with the secondary qualities, using colour as an example, while the following section will deal with the primary qualities, usin shape as the example. We begin with a real case. The current theory about colou perception involves what are called 'Opponent Systems.' According to this theor people have three different kinds of cones in their eyes. Each kind contains a pigment particularly sensitive to a given wavelength of light, each a different one from the others, though each cone type is also somewhat sensitive to the wavelengths that the others are particularly sensitive to. Three kinds of primary processes, or channels, farther along in the visual system--in the ganglia of the retina and again in the lateral geniculate nucleus, for instance--receive information from these three cone types and play a major role in processing this information. These three processes represent opponent (complementary) pairs of colours (red-green, blue-yellow, black-white), depending on whether the activity of these cells is increased or inhibited, and on how their firings are summed. When the cells that make up the cones are activated by an incoming light source, these opponent-process areas of the brain, as well as others, receive and compute the data from the cones and, afte much processing, colour phenomena and beliefs about an object's colour are produced. The relation of wavelengths to perceived colours is not one-to-one. Among other things, our perceptual judgement that an object is red, say, can be initiated by combinations of wavelengths, not just by a single wavelength. Despite this lack of one-to-one correspondence between wavelengths and colour judgements, an important feature of the theory is that it explains perceptual deficits such as colour blindness.

Most colour-blind people are so only with respect to red and green. They cannot easily, if at all, distinguish one from the other.(7) Such a colour blindness can be explained by the fact that such people lack one or another light absorbing pigment in their cones, or that there is a breakdown somewhere in the red-green opponent processing cells somewhere in the system. These people are dichromats as opposed to normal trichromats.(8) The rare blue-yellow colour blindness can be explained in a similar way (though not exactly similar, since there appears to be no light-absorbing cone pigment whose dominant wavelength corresponds to the yellow range for most observers), as can the even rarer tota colour blindness (only the black-white, the 'lightness', system is fully functional) (see Hurvich [1981]).

If such a theory had been available to Locke, given the many-one correspondence from world to perceived colour, it would likely have reinforced his claim that colours, as nonrelational properties, are not in the world but in us. And if in us, then phenomenal properties.(9) But one needs to look further into the cases before drawing this conclusion. While most colour blindness is innate and probably of genetic origin, some colour blindness is brought about by disease o physical injury. Some people with traumatic colour blindness (though none with innate colour blindness) recover many (though not all) of their discrimination powers when appropriately tinted lenses are inserted. A peculiarity is that som of the lens wearers, while able to make colour discriminations they made before say that colours look different to them (Hurvich [1981], pp. 256-7).(10) I take their claim to mean that their phenomena are different. Similar to these cases are those of the deuteranopes mentioned in footnote 7. Deuteranopes are most often able to distinguish green from red when we do; but, given their deficit, it seems unlikely that their basis for doing so would be the same as ours. The differences, whether structural or chemical, in their perceptual systems raise doubts as to whether they experience 'green' phenomena at all. Similarly, the anomalous trichromats mentioned in footnote 8 seem to make the colour discriminations we make; but, again, it is doubtful that they have the same phenomena we have. Such cases as these strongly suggest that people can agree o a wide range of colour judgements while experiencing different phenomena.(11) Hurvich does not make altogether clear whether the lens wearers claim that thei phenomena differ in hue (what we normally think of as colour) from the phenomen they previously had, or in intensity, or in saturation, or in some even more radical way. It is significant that we can conceive of these phenomena differin in any of the four ways.(12) In short, we can conceive that different persons, although agreeing that something is red, have quite different phenomena.

In the case of hue, our intuitions along these lines have been expressed in Inverted Spectrum problems. Two people could agree on their colour judgements, but one of them, on judging objects to be red, would have phenomena just like those the other has when he or she judges objects to be green and vice versa fo green objects.(13)

If such a possible case is actual, should one say that the person with the 'green' phenomena, even though judging these objects to be red, just as the other does, does not really see red? Even more pointedly, should we say the person does not really have red phenomena? But on what grounds? Suppose half th population is one way and half the other, what should be said? Which phenomena are really red? Most philosophers who have dealt with the Inverted Spectrum see committed to claiming that half of such a population would not be seeing red in such cases, or that 'red', as used by half the population, would be a homonym o that same word as used by the other hall or that the two halves are not really communicating or making like judgements, that they only seem to be agreeing in their colour judgements. As far as I can see, the only reason for making such claims is the assumption that phenomena have the property of colour. But, by hypothesis, these two half-populations do agree on their colour judgements, the do draw similar inferences, they do behave in similar ways. These facts lead to the conclusion that these people are not only apparently, but actually, making the same colour judgements. If one rejects the assumption that colours are properties of phenomena, one need not take any of the strange positions philosophers have taken when confronted with this problem. Red is a property of real, external things, if it is a property of anything. The phenomenon, which i part of the process by which we represent that property, is neither red nor any other colour. Even if phenomena be representations, representations do not have to possess the property they represent. But, more to the point, if we do not 'read off' from some phenomenal red of the phenomenal state, then there is as yet no good reason to believe that phenomena are themselves representations at all. I am not arguing that phenomena play no causal role in our conceiving of, or representing, red. I am denying only that they do so by being red and that w are rationally compelled to believe that we read our perceptual judgements off of our phenomena. We do not acquire our concept of 'red' by first seeing some internal object that is red--even if there be internal objects that in some sense we can be aware of.

While there is some evidence (our genetic and anatomical similarity) that most of us have similar phenomena when judging things to be red, there is still much to find out about colour perception. It is not clear, as far as I know, just where in the system the damage to the lens wearers occurs; so evidence based on anatomical similarity is only of a very general sort. Moreover, these same case provide evidence that changes in the perceptual system can produce different phenomena, while judgements apparently remain (at least largely) the same. Structure and chemistry matter. That realization is very important to the progress of my argument.(14)

2.2 Someone who thinks that phenomena are coloured might fring up the following objection: 'In regard to the question, vis-a-vis the Inverted Spectrum cases, a to whose phenomenon is really red, you have succeeded in showing that the answe is arbitrary. However, while it may be arbitrary that one or the other of these phenomena-types be called 'red', it is not arbitrary to think that, whatever names we give them, the phenomena do differ with respect to colour'.

One ground for raising the objection is that we sometimes ascribe colours to phenomena in the absence of judgements about the world, i.e., sometimes we take the phenomena as in-themselves rather than as representations of something else For instance, one talks about one's after-images as being red or blue or green while not believing or judging that this colour property is, in this instance, property of anything external. We do talk this way, but perhaps such talk is only elliptical for 'I am having the same kind of phenomenon I normally have when I perceive real things to be red'. If one believes that such expressions are elliptical, then one will also conclude that the fifty-fifty population cas (and similarly each other Inverted Spectrum case) is misdescribed. If it is thi elliptical sense in which phenomena can be said to be red, the phenomena of bot halves of the population, when faced with a red object, are red. None of them i green.(15) The phenomenon gets categorized according to the 'real'(16) property not vice versa: and such a categorization is always an elliptical one, not a literal ascription of colours to phenomena (even if mistakenly thought to be).

Either reading of our after-image talk (that such talk is elliptical or nonelliptical) accords with the evidence presented so far. The discussion in th next section provides reasons for thinking that such talk is elliptical.

2.3 There are Inverted-Spectrum-like problems that the objection raised in the previous section is apparently unable to account for. When I was a student in philosophy classes, my teachers used to tell me about machines that could be strapped onto blind people. The machines. activated by incoming light of different wavelengths would 'interpret' that light, 'read' out the colour of th object, and then 'signal' the blind people by various scratchings on their backs, so that the blind people arrived at colour judgements that accorded with those of normal-sight persons. What are we to say of these scratches the blind people feel? Suppose that whenever and only whenever scratch-type x occurs the blind people judge the object to be red, and suppose their other judgements apparently agree with ours. Are the blind people's phenomena red? Why not? Or better: Why not, if ours are? Are the grounds not the same for calling one or the other red?

One might object that the causal route exemplified in the machine case shows that the scratches cannot be taken literally as colour phenomena. So suppose instead that the Opponent Systems Theory of colour perception holds for a race of alien beings, if it holds for us. These beings even have eyes with the same three types of cones we have. However, that part of the brain which processes the data from these cones is somewhat different from our own. Remembering from the lens wearer case that differences in brain structure and chemistry can brin about different phenomena, we can easily conceive that the colour phenomena of such aliens are similar to our scratches. Because of these 'scratches', they ar able to make the same colour discriminations we make. Their philosophers even worry about whether one of them might have an inverted spectrum. Suppose that these 'scratches' are quite unlike any other phenomena these aliens experience. Would the aliens not have exactly similar reasons for thinking their 'scratches were red, green, blue, and so on as we do for thinking our phenomena are? Would any defender of the Phenomenological View be willing to say that the phenomena of these aliens differed from ours in colour? It is doubtful. Yet, one would have no grounds for denying the claim, if willing to make a similar claim about human Inverted Spectrum cases. The correct claim is that neither their phenomen nor ours are red, green, blue, or any other colour. Phenomena, whatever properties they do have, are colourless. Insofar as we or the aliens talk about phenomena having colours, as we do with after-images, it is an elliptical way o talking. Ascribing colours to phenomena is a parasitic kind of ascription.

One might object to the fanciful nature of my conceivable cases. However, such an objection is off the mark. It is only conceivability, not actuality, I need to make my point. But, there is more to be said. Most nonprimates seem to have quite different neural-visual structures from ours. Yet some of these animals make quite good colour distinctions. There is a species of freshwater fish, wit a very different neural-visual structure from ours, that seems to be very adept at colour discriminations (Hurvich [1981], p. 138). The evidence from the lens wearer cases is that differences in neural structure/chemistry mean differences in phenomena. Given the very different structure/chemistry of the brains of these fish from ours, there is reason to believe that their phenomena must be very different from our own, perhaps as different as the 'scratches' of the aliens I hypothesize about. So my 'fanciful' world may be the real world.

2.4 Phenomena are colourless, and similar considerations apply to any of the other secondary qualities. And once we realize phenomena are colourless, the 'read-off' position becomes less plausible, especially if we realize that phenomena obtain their descriptors in a borrowed fashion (see Nelkin [1987a], [1989b] for further arguments for the truth of this claim). Before turning to the primary qualities, however, I want to consider a remaining question: 'As yo yourself point out, the current theory of colour perception, because of its many-one nature, seems to give prima facie support to the idea that colours are in us, are properties of our phenomena. But, as you have shown, colours are not phenomenal properties. So what are they?' There are two possible answers to thi question, neither of which puts colour inside us. The first is to claim that although there is no one-to-one correspondence between wavelength(17) and colour, colours are natural kinds; there are lawful many-one relationships that allow us to pick out a particular set (with a potentially infinite number of members) of wavelength groupings as being a colour such as red. The second answer is instead to deny altogether that colours are natural properties. We will have to take this latter tack if there is no lawful base to the set of wavelengths that cause us to judge that an object is red. In that case red will not exist as a natural kind. However, even if we have to accept this latter result, there are two positions that may be open to us: (1) Although colour is not a natural kind, it is still a property of external things. Large and being tree are not natural kinds either, but those facts are hardly grounds for sayin that large and being a tree must therefore be properties of internal phenomena and not of external things. (2) Colour is more like being a witch or being a unicorn, i.e., genuinely non-existent, a mere fiction. But just as witchhood an unicornness are not properties of phenomena, neither are we compelled to say colour is. Too many philosophers have failed to see that the first alternative might be a genuine one. Certainly, no one has pursued it. It strikes me as wort pursuing. In any case, neither alternative turns colour into a property of phenomena.

That we could find out that colour is not a natural kind or that we could come to the conclusion that there are no coloured objects, provides further evidence that colours are not properties of phenomena, nor, in one important sense, were thought to be: Our expectation is that colour is a property in the world, one whose structure is to be discovered. We are surprised when Hardin [1988] gives such convincing reasons to think that there is no lawful physical structure tha is correlated with our colour judgements in any convincing fashion. Of course, if we decide that colour is not a natural kind or perhaps has no instantiation in the external world, we could come to say that colour is henceforth the name of whatever phenomenon we experience when we say or think something has a colour. No great harm done, as long as one realizes that, as the above inverted-spectra-like arguments have shown, such a set of phenomena will not itself form a natural kind. Different kinds of phenomena (ours and the 'scratches' of the aliens, among others) will compose the set.(18)

But if my view is compatible with there being no colours, would it not be bette to admit that colours are only phenomenal properties and not in external objects? Why not simply deny that nonhuman animals and the aliens experience colours? The phenomena underlying human colour perception would then form a natural kind: colour itself.

Granted that the claim that there might turn out to be no colours is counterintuitive, the view that colours are phenomenal properties is far more counterintuitive. It would require conceptual and linguistic revisions far beyond any my view demands. When we learn colours, we do not learn to ascribe them to our experiences. We learn to ascribe them to books, paints, horses, hair, and so forth. Most people would be as surprised to learn that there are not any colours in the external world as to learn that there are not any colour at all. We no more, in our initial learning of colour concepts, learn to think of colours as inner properties than we learn to think of being a rabbit as a property of inner experience. But why should we think of one property more than the other as being inner? Just as rabbits eat and drink while phenomena do not, colours can be mixed, daubed on canvasses, dyed, and so forth. This externality of colours is so deeply embedded in our concept that I see no reason to change our concept unless there are very good theoretical reasons for doing so. What are they? Calling the inner properties 'colours' would not make these propertie any more perspicuous to us than admitting that we have no nonparasitic names fo them, and it might--and has--made us think we know more about them than we do.

A second reason for opposing this move is that just as the aliens might use phenomena similar to our scratchings in their representation of colour, other beings might use phenomena similar to the ones we use in our colour representations in representing properties other than colour. That is, there is no conclusive reasons to think that human colour phenomena form a natural kind as colour phenomena.

Finally, just as on my view it is an empirical possibility that there are no colours, it is an empirical possibility on the Phenomenological View that only one person is aware of colours, i.e., it is an empirical possibility that no tw people share the same kinds of phenomenal properties. We may have good reason t think this possibility is highly unlikely. Yet, as we have seen, agreement in judgement cannot be a clinching reason. Instead, the primary evidence is that w are all members of the same species and so have similar genetic and neural structures. However, this sort of evidence is weaker than one might think. Ther are three kinds of central nervous system neurons: sensory neurons, intermediat neurons, motor neurons. We know a fair amount about the first and the third, bu Nauta and Feirtag were able to say as recently as 1979 that we know almost nothing about the intermediate neurons. Yet these intermediate neurons make up 98.8 per cent of the total and are the locus of most perceptual activity, almos certainly doing the bulk of the computational work (Nauta and Feirtag [1979], p.92). While much more is known now than in 1979 about the intermediate neurons whether these neurons and their connections are relevantly similar from person to person remains an open question. Since the question is open for the bulk of neurons, the evidence cited is not particularly weighty in itself. Moreover, there is some reason to think that brains, even within a species, are highly individualized; and as the lens wearer case indicated, difference in structure/chemistry can bring about differences in phenomena. It really is not obvious that even persons have similar phenomena when making similar colour judgements. So if there is an empirical possibility that creates a counterintuition in my view, there is equally an empirical possibility of an at least as great counterintuition in the Phenomenological View.


3.1 When we turn to the primary qualities, similar considerations lead us to similar conclusions: Our phenomena have no shape or size or extension or position or motion.(19) Using shape as an example, let us first consider the property of being square. Again, the handed-down picture is that we ascribe being square to objects in the real world on the basis of the phenomenal squareness we experience. Pointing inwardly to our phenomenon, we feel tempted to say something like, 'If that's not what square is, what could square be?'(20 Considered thought about Inverted-Spectrum and extended Inverted-Spectrum cases caused us to surrender similar intuitions about colour, and there are analogous considerations in the case of shape.

Parallel to the Inverted-Spectrum cases might be the following kind of cases. Suppose that two persons agree on which objects are square, which are rhombuses which are circles, and so forth. Could they, when standing directly over squares, experience different phenomena? Sure, why not? Suppose that one has a kind of phenomenon the other has only when standing over a particular-angled rhombus. Is this impossible? Suppose also that the phenomena which accompany th first's perception of protractors, and the like, also differ systematically fro the other's. Each would have the same reasons to think that his or her phenomenon was really square. And, again, we can imagine populations being spli evenly between these kinds of experiencers. So which phenomenon is really square? Which is really rhomboid? As with colours, any answer is arbitrary. One might argue that both phenomena at least must have four sides, but what counts as a phenomenon's having four sides is itself as vulnerable to Inverted-Spectru considerations as whether a phenomenon is square or rhomboid. It might be empirically true that only some sorts of phenomena can successfully play a role in the representation of squares. If so, we do not know what the constraints might be. All we have so far is that, for each of us, only certain sorts of phenomena do play a role in the representation of squares; and given the structural similarity of other human brains, it is somewhat likely that other human beings are similarly constrained. However, as we have seen before, such very general evidence is quite weak.

3.2 Bringing in the word 'human' here may help us realize that extended Inverted-Spectrum issues can enter the discussion of shape as well as of colour For instance, suppose one were to interject the claim: 'While there may be a certain arbitrariness in calling a phenomenon "square" or "rhomboid," still suc phenomena have shape and differ from each other by having different shapes. Granted that there will be a many-one relationship from phenomenal shape to rea shape, that should be no more surprising a fact than that there is a many-one relationship from retinal image shape to real shape.' As with the similar objection concerning colour, our reply involves extending Inverted-Spectrum considerations. Consider some nonhumans. These nonhumans--I will call them 'Computeresers'--have eyes very similar to ours. In particular, they have retinas like our own; and their retinal images are similar to ours. However, their brain structure that computes the retinal data is very different from our own. The phenomena Computeresers experience in shape perception are ones we would associate as images of arabic numerals arranged linearly in sets, members of the sets separated by commas, and so on. Moreover, Computeresers never have visual phenomena like these except in the case of shape (their phenomena associated with numbers are very different). Suppose that each of these types o numerical phenomena is associated with a particular shape. Moreover, Computeresers draw all the inferences about squares we do. The question asked earlier is, then, to be asked again: 'Would Computeresers have the same reasons we have for thinking their phenomena really were square, round, triangular, and so forth?' It is hard to see why not. So which phenomena really are square, theirs or ours? And if the answer to that question is seen to be arbitrary, the one should come to the conclusion that neither their phenomena nor ours are square, nor any other shape.

If one is worried by the fancifulness of the example, there are cases we can conceive of a lot closer to our human home. People born blind presumably have n visual phenomena. We can likewise imagine people born unable to have phenomena of touch, or even kinaesthetic phenomena. Blind people have only tactile shape phenomena; the others have only visual phenomena. Which of these sets of phenomena really has the property of shape? As Locke ([1690/1959], p. 186-7) himself claimed, it is unlikely that people born blind, who had had their sight restored, would recognize shapes when seeing them for the first time.(21) Our visual phenomena associated with shape just are very different from our tactile ones, and it is difficult to believe they have anything in common except for this association.

3.3 It is reasonable to conclude that shape (or, similarly, any other primary quality) is not a property of phenomena. Moreover, unlike with colour, we do have good reasons for thinking that the primary qualities are properties of the external world. Thus we have arrived at the point where Berkeley is turned onto his feet: both the primary and secondary qualities, considered as nonrelational are properties of real objects, not of phenomena, if properties of anything at all. And once we come to this realization, we again can see that the attractiveness and attraction of a 'read-off' position all but disappear.

At the end of Section 2.4, at a similar stage of argumentation for the secondar qualities, I raised an objection to my own conclusion: There are good theoretical reasons for treating the qualities as in us rather than as in objects. As applied to the primary qualities, this objection is so counterintuitive that even the originators of the Phenomenological View refused to believe it. I know of no defense for it, except perhaps for the argument to be considered in the next section.


'Phenomena have a natural intentionality about them. This natural intentionalit makes us think that in perceptual experience we are directly aware of the properties of external objects, while all we are really aware of are our own phenomena. Because of the natural intentionality of phenomena, we come to ascribe properties to external objects that we should not be ascribing to them at all. In particular, we are apt to confuse the relational properties of external things with nonrelational properties of phenomena. Thus, we are directly aware of the nonrelational phenomenal property and because of its natural intentionality thereby ascribe is red to the object. The red we ascribe to the object is the phenomenal property itself. Later, when we learn external objects can not have this nonrelational property, we quite naturally continue t say objects are red. But now by 'red' we mean a relational property of that object, namely, that which causes red phenomena in us. Thus, it is you who have stood matters upside down: 'Red' is primarily used as a word to designate a property of phenomena. It is only parasitically and elliptically used as a property of objects' (see, for instance, Perkins [1983] and Jackson [1977]). This is not an implausible objection, but there are good reasons to think it wrong. The objection slides from the possible truth that we make our property ascriptions to external objects (at least partly) because of our phenomena to the false claim that we ascribe the properties of the phenomena themselves to the objects. It is this slide I take to be unwarranted. Let me present three ne sorts of consideration opposed to this view and in support of the position I have maintained throughout this paper (I have already given some in Section 2.4 and will give others in the next section).

(i) We have no inclination to think that this description of our phenomenology and resultant property ascriptions applies in the case of most properties we ascribe to external objects. Consider the property of being water. We certainly ascribe being water to a piece of the world on the basis of its feeling and looking a certain way to us. But being water was never (idealists aside) considered a property of our phenomena, even as a collection of such properties That is why Berkeley's claim that things are collections of phenomena is usuall received with such amazement and disbelief. Nor did we ever take being water to be a mere relational property (one that causes 'water' phenomena in us), though we believe that that property (or the piece of the world with that property) ha certain causal powers, including the power to cause certain phenomena in us. Rather, when ascribing being water (or being a rabbit, or any other external property) we were quite open as to the real nature of that property. In that sense, we were neutral about that property. That is why we could discover that water could be steam or ice as well as liquid. Even more important and relevant it is also why we could discover that being water is being [H.sub.2]O. We have had no difficulty accepting that some piece of the world can look and feel just like water but not be water; and in making the identification of water with [H.sub.2]O, we have not changed the meaning of the word 'water,' nor its reference. Being water has as its primary use being ascribed to the world. The idea of phenomenal water is very peculiar, indeed.

(ii) This kind of pecularity is even more vivid in the case of being a unicorn. Of course unicorns are figments of our imagination. But it would be a solecism to conclude from that fact that being a unicorn is a property of our phenomena. There are no unicorns. It is a property of no thing. It is its failure to apply to external objects that leads us to say that it is not a property of anything, for it was meant as a property of external objects.

(iii) While the objection gets a lot of mileage out of the colour case, it woul have gotten far less mileage if we had considered shape. In the case of square there are both visual and tactile phenomena. Which of these do we ascribe to th world as a nonrelational property? I am not even sure the question makes sense. All we can say is that these sorts of phenomena lead us to ascribe square to some objects in the world. What square is, like what water is, is a question that does not even arise for us until we learn to do science, mathematics, or philosophy. How properties affect us is certainly important to us, but we are most often neutral about the real nature of the nonrelational properties we ascribe to the world. Given how unlikely the story of the objection is for shape, we are justified---especially given the other considerations--in also believing that, despite some apparent plausibility for colour, it is the wrong story there as well. As with the water example above, we do not have to change the meaning of the word 'red' to claim that red things do not always look to be red or that things that are not red can look as if they were. Just as with 'water,' our ascription of 'red' entails no commitment as to the true nature of the property we so ascribe. Colour-blind people, for instance, learn that some things they take to be red or blue are really green or yellow. This parallels the discovery that something that looks like water need not be water.

To these considerations let me add one more consideration, which I think to be of utmost importance. The objection that began this section starts with the assumption that a 'natural intentionality' attaches to our phenomena. This assumption is unwarranted. If there be a natural intentionality in perception, it can be said to attach only to the entire perceptual process. Identifying tha perceptual process with the phenomenal state, without argument that supports that identification, appears to be a part-for-whole fallacy. Perception involve sets of very complicated processes and representational schemes (see Marr [1982], for instance), with the end result somehow being the integration of those processes. At best, and when they occur, phenomena seem to be only a part of this integrated package, a part whose role is far from clear. When one considers the many-one and one-many relations of phenomena to perception, as discussed throughout this paper, it appears highly unlikely that phenomena can bear all, or even a large, share of the weight of perceptual representation.

One of the major motivations behind the Phenomenological View was to make perspicuous how we can conceive the world. The photographic nature (the natural intentionality) of phenomena was proposed to explain this ability. But now we see just how badly that view has failed when we are told that the 'photographs' are not really photographs of anything. To claim that we ascribe phenomenal properties to the world but the world does not have such properties is to retract the Phenomenological View, not to defend it. Any such view as that set out at the beginning of this section will face a question just as difficult as the one my view leaves over: 'How can phenomena, which have none (or only a few of the properties of the external world, enable us to conceive the world?' How, that is, is nonphotographic representation possible? It is possible. We use it. And so there is an answer to this question. Since the Phenomenological View has failed to answer the very question that motivated it, and since accepting it would require such extensmve revisions of our concepts of colour and shape, I see no good reason to accept it. But similar considerations apply to any 'read-off' position.


Cases of blindsight (Weiskrantz [1986]), hemineglect with hemianopia (Reingold and Merikle [1990]), visual extinction (Volpe et al. [1979]), and split brains (Gazzaniga [1970] and Gazzaniga and LeDoux [1978]), however controversial these cases are, might mean that there is sometimes perception without any phenomena at all.(22) And if the claim that a human-like left brain is required for phenomenal representation (Gazziniga [1985], p. 131-2) and Gardner ([1985], p. 331) is true, then it may turn out that nonprimate perception never involves phenomena. If so, accepting that phenomena have no colours, shapes, and so fort (the properties we ascribe to the external world), and accepting that we do not 'read off' our phenomena in order to perceive, would allow us to understand our perceptual system as not being altogether different from these others. On the other hand, if colours and shapes were only phenomenal properties, as the Phenomenological View maintains, then nonprimates, blindsight patients, and the other patients would perceive no colours or shapes, whatever discriminations they make. However, we have evidence that blindsight patients can make hue discriminations that apparently incorporate opponent-processing based judgement of the kind normal-sighted people make. Yet these subjects deny having any colour phenomena (Stoerig and Cowey [1989], Weiskrantz [1990], p. 254). And if perception requires phenomenal experience, as defenders of the Phenomenological View have sometimes claimed, then blindsight subjects and the others would not even perceive. Once we realize that we, in fact, get concepts of colours and shapes without any photograph-like processes occurring in our conscious perception, then we need no longer feel compelled to make such counterintuitive claims as these. To the contrary, if we take phenomena not to be 'read off' from, but to be among the noncognitive causes of perception, then we can understand how other brain states might play a substituting role in some cases of perception. We do not have to deny perception of blindsight subjects (or of others who make perceptual discriminations without conscious phenomena). We are much better prepared to come to understanding perception as all of a (however complicated) piece, namely, as primarily being an information-processing, rathe than a phenomenal, state.(23) As such, the raison d'etre of the human system that accomplishes this information processing will, for all its other differences, almost certainly be the same as for any other organism; and studying one system will almost surely throw light on any other. To consider human perception as being primarily a phenomenal state is to misunderstand both the nature of human perception and its relation to the perceptual states of other organisms.

When these theoretical considerations are added to the previous arguments, then even versions of the 'read-off' position less extreme than the Phenomenological View are implausible. Both the earlier arguments and these theoretical considerations make it clear that there is no one conscious phenomenal state-type to be 'read off' in the case of any particular perceptual property--no matter what interpretation (act-object or adverbial) one gives to phenomenal states.

It is important to realize that we ascribe properties such as colour and shape to phenomena only in an elliptical and parasitic manner. For it follows that if we want to talk about phenomena in themselves somewhow, we will have to learn more about their own properties in order to find some other, nonparasitic way o talking about them and categorizing them. We really know very little about phenomena.(24) Only by understanding just how little we know about them, and ho we have been misled concerning them, will genuine research into their nature be able to proceed. What is their role in perception? Are they mere epiphenomena o the perceptual processes or do they play an integral, effective role in perception? These questions need answering, and they will not be answered until we become aware of what we know and, more importantly, do not know about phenomena. I have tried to show just how little we really do know.

On the other hand, it is cognitive processes (both doxastic and subdoxastic, to use the Fodor [1983]--Stich [1978] terms), not phenomena, that bear most of our investigation if we want to understand perception. Phenomena play a smaller rol in our lives than we have tended to think. That claim is supported by the fact that we do not have names for the properties of our phenomena, other than elliptical and parasitic ones. The further we advance our study of phenomena, the more they recede into the background, leaving much that is important in our lives intact even as they do. I am pretty certain, for instance, that almost everything that makes consciousness important to us can be stated without reference to phenomena (Nelkin [1986], [1987b], [1989a]). So even though the mystery of phenomena has not been solved, it looks to be a less and less urgent matter that it be solved. At the same time, it would be nice to solve it.(25)

Department of Philosophy, University of New Orleans

1 Instead of 'phenomena states,' one might write 'phenomena', 'qualia', 'sensa' 'sense-data'. These have, perhaps, had slightly different uses from each other in their philosophic history, but I want to focus on whatever point of overlap they possess. I will most often use the term 'phenomena' rather than 'phenomena states', just because it is shorter than 'phenomenal states' (though 'phenomena has some object-implying connotations that I am not completely happy with). There are those who might be thought to deny any role for phenomena in perception because they deny that there are phenomena at all (Dennett [1988]). do not plan to defend the existence of phenomena in this paper, but I find it hard to believe that there are no such things. Nor do I think Dennett really denies their existence altogether. What I take him to be denying is that they could have the sorts of properties people have ascribed to them. If that is the correct reading of his paper, then he is agreeing with what I have said in previous papers ([1987a]. [1989b], [1990]) and will further develop in this paper.

2 Among the originators of the view in question, the most important is probably Locke [1690/1959]. Locke, however, distinguished the primary qualities from the secondary qualities. He held that colours and the other secondary qualities mak no sense as nonrelational properties of external objects. Such properties are only phenomenal properties (when considered as nonrelational, rather than as relational properties). On the other hand, he held that the primary qualities are nonrelational properties of both phenomena and real objects. Berkeley ([1713/1965], 127 ff) argued that Locke could not have it both ways: the same sorts of considerations, when made about the primary qualities, lead one to a similar conclusion about shape and all. Russell [1948], Broad [1960], and Price [1932], among many other twentieth-century philosophers, held some version of the Lockean view. Current defenders of the view include Moreland Perkins [1983] Frank Jackson [1977], and perhaps Christopher Peacocke [1983]. Among psychologists, Roger Shepard (Cooper and Shepard [1984]) seems to hold somethin like this view. Similarly, Irvin Rock [1983], who, quite like me, wants to downplay the importance of phenomena, nevertheless, often talks as if he really believes that visual images do have properties like colour or shape.

3 Whether external objects exist or not: I am not offering a solution to the problem of skepticism here. That is, if there are external objects, they are th kinds of things that have colour, shape, and so on. And if there are no such things, then that would be a case where nothing has those properties.

4 I am certainly not the first to make the claim that phenomena are not coloured, and so on. Roger Brown and Richard J. Herrnstein ([1981], p. 48) maintain that images of bananas are not yellow, nor soft, nor the like. Zenon Pylyshyn [1981] also holds a view similar to mine. Pylyshyn says that to think that images have ordinary properties is a mistake in scope. It is to slip from 'image of (object x with property P)' to '(image of object x) with property P'. That is a neat way of putting the error. However, arguments showing why this move is an error are harder to find. This paper is an attempt to supply some.

5 While arguing against the 'read-off' position. I will make no attempt to settle the issue completely. In particular, I will make no attempt to argue for the causal position over against the epiphenomenal position, or vice versa. My own belief (usually!) is that the causal view is correct, but there are actual cases which to me, lend some plausibility to the epiphenomenal view (see, for instance. Weiskrantz [1988], p. 189).

6 see Thomas Reid ([1785/1969], p. 242), whose view I believe to be close to my own: 'Almost all our perceptions have corresponding sensations which accompany them, and, on that account, are very apt to be confounded with them ... Hence i happens, that a quality perceived, and the sensation corresponding to that perception, often go under the same name'. See also pp. 28, 60, 130, 242-5, 247 and 257.

7 Actually, there is more than one sort of red-green colour blindness. There ar those (deuteranopes) whose cones lack one light-absorbing dominant pigment (in the green range of light waves for most observers under most conditions) and those (protanopes) who lack, instead, another light-wave dominant pigment (in the red range of light waves for most observers under most conditions). The former, oddly enough, are not totally insensitive to green light, although ther are conditions under which they are unable to distinguish green from combinations of red and blue light on the basis of hue itself. See, for instance, Lloyd Kaufman ([1974], p. 177).

8 There are also trichromatic forms of 'colour blindness.' Some people seem to be sensitive to wavelengths different from the three that most perceivers are sensitive to. These people make many of the same colour judgements as ordinary perceivers; but when they mix wavelengths to match a particular wavelength, the combine a different three wavelengths, quite removed from the ordinary range. (See Kaufman ([1974], p. 178).) It is only under special conditions of testing that actual deficits (in making judgements about relations among hues, for instance) appear (Cavonius, Muller, and Mollon [1990]).

9 C. L. Hardin [1988] provides the fullest, most interesting, and most provocative philosophical discussion of colour perception that I know of. Hardi argues that colours (hues) are not instantiated in the external world. In fact, he argues that they are not instantiated at all. His position, as I understand it, is a kind of Adverbialist position; but, I believe, he also leans toward th 'read off' position of phenomenal states. It is at this point where we most disagree.

10 Hardin, in a personal communication, maintains that the lenses do not enable the subjects to make trichromatic discriminations (hue discriminations) but onl to make corresponding discriminations, by being able to make further lightness discriminations. While Hardin may be right, his being right does not affect the argument. What is really important for my argument is that it is an empirical question as to whether the discriminations are chromatic or lightness based. We can imagine either case.

11 Of course, one might claim that these people are not really agreeing on thei hue judgements: They only seem to be. The range of cases over which they disagree shows that they are not really agreeing even in these cases of apparen agreement. 'Green', say, just means something different to the deuteranope from what it means to most people. A discussion of this issue begins in the next paragraph.

12 To describe one's phenomena as differing in any of these four ways, if meant literally, is really a mistake. Such ways of describing what is going on, whether we realize it or not, are elliptical for longer expressions such as, 'I am now having a phenomenon like the ones I used to have when I perceived blue' (or 'a less highly intense red', or 'a less highly saturated red', or 'the soun of a trumpet'). But since the ellipticality of such expressions is part of my conclusion, I will here talk as if these ways of expressing oneself were all right as they nonelliptically stand.

13 There have been arguments denying the possibility of an inverted spectrum (Shoemaker [1981]--who isn't fully committed to the impossibility, Harman [1982], Hardin [1988]). Despite the appeal of these arguments, the tens wearer and anomalous trichromat cases seem to give empirical reason to believe the arguments are deficient. For a more philosophical critique of the arguments, se Ned Block [forthcoming]. If the arguments against the inverted spectrum nevertheless be correct, they would make my point much more readily. I am willing to grant the Phenomenological View the possibility of inverted spectra. I want to show that even if they be actual, their existence would tell against, rather than for, the Phenomenological View.

14 It is true that there are discriminations normal colour perceivers make (especially about the relations among hues) that the lens wearers and the anomalous trichromats do not make (see Cavonius, Muller, and Mollon [1990]): but, again, what is important is that experiments had to be undertaken to revea these deficits. The discriminatory powers of these nonnormal groups appear unde most circumstances to be perfectly normal. Again, if the discriminations made b these latter groups are nonnormal (even their normal ones!), then that result i discovered by empirical methods. Conceptually, we understand perfectly well tha the experiments could have come out otherwise. Moreover, the interpretation of the results of the experiments showing these deficits will be partly a matter o theory. Why, for instance, should these experiments make us think that these anomalous perceivers differ from us in their phenomena? They certainly differ from us in their judgements, but the explanation of that difference is exactly what is at stake. Even if someone would report a difference in phenomena (havin suddenly become an anomalous perceiver), his or her own introspections would be unable to reveal the role these different phenomena were playing. Any of the three positions set out in the beginning of the paper would be compatible with such facts. It should be kept in mind (see Section 6 for further clarification) that I am not denying the subjectivity of hue judgements. I am instead denying that the best theory to explain our hue judgements will maintain that phenomena are bearers of hues.

15 Note that this result accords with that of the arguments raised against the possibility of inverted spectra, although it is arrived at by allowing for thei possibility.

16 The reason for the shudder-quotes will be clarified in Section 2.4.

17 Or some other physical property, such as reflectance.

18 Though how to square the claim that colours are phenomena with the existence of unconscious colour discriminations (for which there seems to be evidence--Keating [1979], Stoerig and Cowey [1989]) may be a real problem.

19 At least not as we think them to have. However, if it turns out that phenomena are identical to brain processes, then some of these properties, at least, will be truly ascribable to them. But then phenomena will have real position, say, not phenomenal position.

20 Of course, this story leaves out the great complication that exists with shape but not (at least to the same degree) with colour, namely, that most ofte when we judge an object to be square the image we are having is not an image we ourselves would describe as square. We seem to compute, using information about direction and distance to the object, what the real shape of the object is, tha its real shape is square and not one of these nonsquare shapes which our images possess. Since this complication will not enter the argument, the reader is fre to consider only those images people have when an object is in full view while they are standing directly over it or have it directly in front of them. I myself do not think phenomena (or mental images) are square, round, or any othe shape. As with colour, such talk is elliptical and such ascriptions parasitic. But, as in the case of colour, I will allow such talk for a while only in order to show why, when considered nonelliptical, it is illegitimate.

21 Locke's speculations aside, there is good empirical evidence that this failure of recognition can occur, as experiments by von Senden, Riesen, and Gregory and Wallace show (Kaufman [1974], p. 490).

22 Actually, I do not think that the right interpretation is that there are no phenomena in these cases. Rather, it is only that we are not second-order conscious of these phenomenal states (see Nelkin [1989c]). But it is at least empirically and theoretically possible that these are cases of perception without phenomena, and it is only this possibility that I need to make my point

23 See Nelkin [1990] for further arguments in favour of this position.

24 See, for instance, Dennett [1988].

25 I would like to thank C. L. Hardin and Edward Johnson for the critical care

they gave to earlier versions of this paper. Hardin, in particular, helped to make my exposition of the science more correct. I would especially like to than Carolyn Morillo, who h as read this paper in every one of its manifestations. Her comments have helped me greatly.


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Date:Jun 1, 1994
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