The claim that behaviourally undetectable inverted spectra are possible has been endorsed by many physicalists. I explain why this starting point rules out standard forms of scientific explanation for qualia. The modern ‘phenomenal concept strategy’ is an updated way of defending problematic intuitions like these, but I show that it cannot help to recover standard scientific explanation. I argue that Chalmers is right: we should accept the falsity of physicalism if we accept this problematic starting point. I further argue that (...) accepting this starting point amounts to at least implicitly endorsing certain theoretical claims about the nature of introspection. I therefore suggest that we allow ourselves to be guided, in our quest to understand qualia, by whatever independently plausible theories of introspection we have. I propose that we adopt a more moderate definition of qualia, as those introspectible properties which cannot be fully specified simply by specifying the non-controversially introspectible ‘propositional attitude’ mental states (including seeing x, experiencing x, and so on, where x is a specification of a potentially public state of affairs). Qualia thus defined may well fit plausible, naturalisable accounts of introspection. If so, such accounts have the potential to explain, rather than explain away, the problematic intuitions discussed earlier; an approach that should allow integration of our understanding of qualia with the rest of science. (shrink)

To the familiar idea of an undetectable spectrum inversion some have added the idea of inverted earth. This new combination of ideas is even harder to make coherent, particularly as it applies to a supposed inversion of black and white counteracted by an environmental switch of these. Black and white exhibit asymmetries in their connections with illumination, shadow and visibility, which rule out their being reversed. And since the most saturated yellow is light and the most saturated blue dark, yellow (...) and blue could not be reversed unless light and dark could be. The difficulties suggest some more general morals for how to think of the role of 'qualia' in colour perception. (shrink)

Intentionalism debates seek to uncover the relationship between the qualitative aspects of experience—phenomenal character—and the intentionality of the mind. They have been at or near center stage in the philosophy of mind for more than two decades, and in my view need to be reexamined. There are two core distinct intentionalism debates that are rarely distinguished (Sect. 1). Additionally, the characterization of spectrum inversion as involving inverted qualities and constant intentional content is mistaken (Sect. 3). These confusions can be witnessed (...) from an often-ignored and lonely perspective, that of the sense-datum theorist, and in particular of the projectivist (Sect. 2). In my view we have been so wary of sense-datum theory in recent years that we have failed to see that, even if false, it may permit perspectives on intentionalism issues difficult to occupy from other views. (shrink)

As Gert says, the basic claim of representationism is that the phenomenal character of an experience supervenes on its representational content. Restricted to color experience, representationism may be put as follows.

Qualia inversion thought experiments are ubiquitous in contemporary philosophy of mind (largely due to the influence of Shoemaker 1982 and Block 1990). The most popular kind is one or another variant of Locke's hypothetical case of.

Palmer's subjectivity barrier seems to be erected on a popular but highly suspect conception of visual experience, and his color room argument is invalid.

Philosophers have devoted a great deal of discussion to the question of whether an inverted spectrum thought experiment refutes functionalism. (For a review of the inverted spectrum and its many philosophical applications, see Byrne, 2004.) If Ho?man is correct the matter can be swiftly and conclusively settled, without appeal to any empirical data about color vision (or anything else). Assuming only that color experiences and functional relations can be mathematically represented, a simple mathematical result.

Philosophers who advocate the possibility of spectrum inversion often conclude that the qualitative content of experiential states pose a serious problem for functionalism. I argue that in order for the inversion hypothesis to support this conclusion one needs to show that it generalizes to all species of qualia. By examining features of touch, taste, and olfactory sensations, I show there is good reason to resist this generalization, in which case appeals to the possibility of spectral inversion are considerably less effective (...) than they may initially appear. (shrink)

I argue that the inverted spectrum hypothesis is nota possibility we should take seriously. The principlereason is that if someone's qualia were inverted inthe specified manner there is reason to believe thephenomenal difference would manifest itself inbehaviour. This is so for two reasons. First, Isuggest that qualia, including phenomenal colours, arepartly constituted by an affective component whichwould be inverted along with the connected qualia. Theresulting affective inversions will, given theintimate connections that exist between emotions andbehaviour, likely manifest themselves in behaviour, (...) inwhich case the underlying phenomenal differences canbe functionally captured. Second, I argue that othersense modalities lack the structural featuresnecessary for undetectable inversion which, because oftheir analogy with colour qualia, weakens theplausibility of such an inversion in the original caseof vision. (shrink)

In ‘Wittgenstein and Qualia’ Ned Block argues for the existence of inverted spectra and those ineffable things, qualia. The essence of his discussion is a would-be proof, presented through a series of pictures, of the possible existence of an inverted spectrum. His argument appeals to some remarks by Wittgenstein which, Block holds, commit the former to a certain ‘dangerous scenario’ wherein inverted spectra, and consequently qualia live and breath. I hold that a key premise of this proof is incoherent. Furthermore, (...) Block’s dangerous scenario does not follow from Wittgenstein’s innocent one, as Block believes it does, but rather is in conflict with it. (shrink)

Subjectivists hold that you cannot specify color kinds without implicitly or explicitly referring to the dispositions of observers. Even though "yellow" is ascribed to physical items, and presumably there is something physical in each such item causing it to be so characterized, the only physical similarity between all such items is that they all affect an observer in the same way. So the principles organizing the colors are all found within the skin.

The possibility that what looks red to me may look green to you has traditionally been known as "spectrum inversion." This possibility is thought to create difficulties for any attempt to define mental states in terms of behavioral dispositions or functional roles. If spectrum inversion is possible, then it seems that two perceptual states may have identical functional antecedents and effects yet differ in their qualitative content. In that case the qualitative character of the states could not be functionally defined.

Formerly a spectral apparition that haunted behaviorism and provided a puzzle about our knowledge of other minds, the inverted spectrum possibility has emerged as an important challenge to functionalist accounts of qualia. The inverted spectrum hypothesis raises the possibility that two individuals might think and behave in the same way yet have different qualia. The traditional supposition is of an individual who has a subjective color spectrum that is inverted with regard to that had by other individuals. When he looks (...) at red objects, this individual has the qualia normally produced in others by blue objects. And when presented with a blue object, this individual experiences qualia that most persons experience only when presented with red objects. And so forth - the Invert's color spectrum is the inverse of normal; there are systematic inter-subjective differences in qualia. (shrink)

Functionalism, a philosophical theory, has empirical consequences. Functionalism predicts that where systematic transformations of sensory input occur and are followed by behavioral accommodation in which normal function of the organism is restored such that the causes and effects of the subject's psychological states return to those of the period prior to the transformation, there will be a return of qualia or subjective experiences to those present prior to the transform. A transformation of this type that has long been of philosophical (...) interest is the possibility of an inverted spectrum. Hilary Putnam argues that the physical possibility of acquired spectrum inversion refutes functionalism. I argue, however, that in the absence of empirical results no a priori arguments against functionalism, such as Putnam's, can be cogent. I sketch an experimental situation which would produce acquired spectrum inversion. The mere existence of qualia inversion would constitute no refutation of functionalism; only its persistence after behavioral accommodation to the inversion would properly count against functionalism. The cumulative empirical evidence from experiments on image inversion suggests that the results of actual spectrum inversion would confirm rather than refute functionalism. (shrink)

As a lefthanded person, I can wonder whether I am a left-hemisphere-dominant speaker or a right-hemisphere-dominant speaker or something mixed, and the only way I can learn the truth is by submitting myself to objective, Athird-person@ testing. I don =t Ahave access to @ this intimate fact about how my own mind does its work. It escapes all my attempts at introspective detection, and might, for all I know, shunt back and forth every few seconds without my being any the (...) wiser. In striking contrast to this is the traditional idea that there are. (shrink)

Philosophers have adopted various names for the things in the beholder (or properties of the beholder) that have been supposed to provide a safe home for the colors and the rest of the properties that have been banished from the "external" world by the triumphs of physics: "raw feels", "sensa", "phenomenal qualities" "intrinsic properties of conscious experiences" "the qualitative content of mental states" and, of course, "qualia," the term I will use. There are subtle differences in how these terms (...) have been defined, but I'm going to ride roughshod over them. I deny that there are. (shrink)

Michael Tye’s considered position on visual experience combines representationalism with externalism about color, so when considering spectrum inversion, he needs a principled reason to claim that a person with inverted color vision is seeing things incorrectly. Tye’s responses to the problem of the inverted spectrum ( 2000 , in: Consciousness, color, and content, The MIT Press, Cambridge, MA and 2002a , in: Chalmers (ed.) Philosophy of mind: classical and contemporary readings, Oxford University Press, Oxford) rely on a teleological approach to (...) the evolution of vision to secure the grounds upon which people with normal color vision can be justly called ‘right’ and those with inverted color vision can be called ‘wrong’. I demonstrate that since the inverted spectrum thought experiment requires that both sorts of vision be behaviorally indistinguishable, no biologically acceptable concept of teleology will allow Tye to draw the distinction he needs. (shrink)

This expanded edition of C L Hardin's ground-breaking work on colour features a new chapter, 'Further Thoughts: 1993', in which the author revisits the dispute ...

This paper attempts to refute the familiar sceptical argument based upon the theoretical possibility of systematic transpositions of colours in different observers? colour?vision. The force of this argument lies in its apparent demonstration that cases of transposed colour?vision would be on a quite different cognitive footing from ordinary cases of colour?blindness; since colour transposition, unlike colour?blindness, could not possibly have any effect on the use of language by a person who suffered from it. It is argued (1) that this demonstration (...) works only if we assume the truth of a certain theory of the logical nature of our colour vocabulary, and (2) that this theory is false. (shrink)

It seems intuitively obvious that metameric matching of color samples entails a loss of information, for spectrophotometrically diverse materials appear the same. This intuition implicitly relies on a conception of the function of color vision and on a related conception of how color samples should be individuated. It assumes that the function of color vision is to distinguish among spectral energy distributions, and that color samples should be individuated by their physical properties. I challenge these assumptions by articulating a different (...) conception of the function of color vision, according to which color vision serves to partition object surfaces into discrimination classes. (shrink)

If you trained someone to emit a particular sound at the sight of something red, another at the sight of something yellow, and so on for other colors, still he would not yet be describing objects by their colors. Though he might be a help to us in giving a description. A description is a representation of a distribution in a space (in that of time, for instance).

If you trained someone to emit a particular sound at the sight of something red, another at the sight of something yellow, and so on for other colors, still he would not yet be describing objects by their colors. Though he might be a help to us in giving a description. A description is a representation of a distribution in a space (in that of time, for instance).

Robert Kirk uses the notion of "raw feeling" to bridge the intelligibility gap between our knowledge of ourselves as physical organisms and our knowledge of ...

In this paper, I shall evaluate a strategy recently used to try to demonstrate the impossibility of behaviorally undetectable spectrum inversion. After showing that the impossibility proof proves too much, I shall identify where it goes wrong. In turn, I shall explain why someone attracted to functionalist and representationalist assumptions might rightly remain agnostic about the possibility of inversion.

Purest points of Hering's six primary colors reside at different levels of lightness such that inversion of each hue pair would be detectable in subjects' choice of foci on the Munsell array. An inverted spectrum would not impose the isomorphism constraint on a contrast of red-green or yellow-blue, whatever we conclude about inference in functionalism.

In this paper I examine whether representationalism can account for various thought experiments about colour inversions. Representationalism is, at minimum, the view that, necessarily, if two experiences have the same representational content then they have the same phenomenal character. I argue that representationalism ought to be rejected if one holds externalist views about experiential content and one holds traditional exter- nalist views about the nature of the content of propositional attitudes. Thus, colour inver- sion scenarios are more damaging to externalist (...) representationalist views than have been previously thought. More specifically, I argue that representationalists who endorse externalism about experiential content either have to become internalists about the content of propositional attitudes or they have to adopt a novel variety of externalism about the content of propositional attitudes. This novel type of propositional attitude externalism is investigated. It can be seen that adopting it forces one to reject Putnam. (shrink)

There has been much written in recent years about whether a pair of subjects could have visual experiences that represented the colors of objects in their environment in precisely the same way, despite differing significantly in what it was like to undergo them, differing that is, in their qualitative character. The possibility of spectrum inversion has been so much debated1 in large part because of the threat that it would pose to the more general doctrine of Intentionalism, according to which (...) the representational content of an experience fixes what it. (shrink)

Susan Hurley has attacked the ''Duplication Assumption'', the assumption thatcreatures with exactly the same internal states could function exactly alike inenvironments that are systematically distorted. She argues that the dynamicalinterdependence of action and perception is highly problematic for the DuplicationAssumption when it involves spatial states and capacities, whereas no such problemsarise when it involves color states and capacities. I will try to establish that theDuplication Assumption makes even less sense for lightness than for some ofthe spatial cases. This is due (...) not only to motor factors, but to the basic physicalasymmetry between black and white. I then argue that the case can be extendedfrom lightness perception to hue perception. Overall, the aims of this paper are:(1) to extend Susan Hurley''s critique of the Duplication Assumption; (2) to argueagainst highly constrained versions of Inverted Spectrum arguments; (3) to proposea broader conception of the vehicle for color perception. (shrink)

Palmer's target article is surely one of the most scientifically detailed and knowledgeable treatments of spectrum inversion ever. Unfortunately, it is built on a very shaky philosophical foundation, the notion of the "intrinsic". In the article's ontology, there are two kinds of properties of mental states, intrinsic properties and relational properties. The whole point of the article is that these aspects of experience are mutually exclusive: the intrinsic is nonrelational and the relational is nonintrinsic.

In restricting his analysis to the causal relations of functionalism, on the one hand, and the neurophysiological realizers of biology, on the other, Palmer has overlooked an alternative conception of the relationship between color experience and the brain - one that liberalises the relation between mental phenomena and their physical implementation, without generating functionalism.

The relations among consciousness, brain, behavior, and scientific explanation are explored in the domain of color perception. Current scientific knowledge about color similarity, color composition, dimensional structure, unique colors, and color categories is used to assess Locke.

The principle of functional invariance states that it is a natural law that conscious beings with the same functional organization have the same quality of conscious experience. A group of arguments in support of this principle are rejected, on the grounds that they establish at most only the weaker intra-subjective principle that any two stages in the life of a single conscious being that duplicate one another in terms of functional organization also duplicate one another in terms of quality of (...) phenomenal experience. (shrink)

Martine Nida-Rümelin (1996) argues that color science indicates behaviorally undetectable spectrum inversion is possible and raises this possibility as an objection to functionalist accounts of visual states of color. I show that her argument does not rest solely on color science, but also on a philosophically controversial assumption, namely, that visual states of color supervene on physiological states. However, this assumption, on the part of philosophers or vision scientists, has the effect of simply ruling out certain versions of functionalism. While (...) Nida-Rümelin is quite right to search for empirical tests for claims about the nature of visual states, philosophical issues remain pivotal in determining the correctness of these claims. (shrink)

Martine Nida-Rümelin (1996) argues that color science indicates behaviorally undetectable spectrum inversion is possible and raises this possibility as an objection to functionalist accounts of visual states of color. I show that her argument does not rest solely on color science, but also on a philosophically controversial assumption, namely, that visual states of color supervene on physiological states. However, this assumption, on the part of philosophers or vision scientists, has the effect of simply ruling out certain versions of functionalism. While (...) Nida-Rümelin is quite right to search for empirical tests for claims about the nature of visual states, philosophical issues remain pivotal in determining the correctness of these claims. (shrink)

In this commentary I point out that Palmer mislocates the source of the inverted spectrum, misrepresents the nature of colour science, and offers no reason for prefering one colour machine over another. I conclude nonetheless that talk about “colour machines” is a step in the right direction.

Sydney Shoemaker is one of the most influential philosophers currently writing on philosophy of mind and metaphysics. The essays in this collection deal with the way in which we know our own minds, and with the nature of those mental states of which we have our most direct conscious awareness. Professor Shoemaker opposes the 'inner sense' conception of introspective self-knowledge. He defends the view that perceptual and sensory states have non-representational features - 'qualia' - that determine what it is like (...) to have them. Amongst the other topics covered are the unity of consciousness, and the idea that the 'first-person perspective' gives a privileged route to philosophical understanding of the nature of mind. This major collection is sure to prove invaluable to all advanced students of the philosophy of mind and cognitive science. (shrink)

Let me begin by indicating where I think Harman and I are in agreement. We both think that "subjective reactions" must come into an account of color, although we have different views about how they do. We both think that perceptual experience has a "presentational or representational character," and that color is represented by our visual experiences as a feature of external objects, not as a feature of our experience. Moreover, we agree that, as Harman puts it, "color is experienced (...) as a simple basic quality, rather than a disposition or complex of causal properties." As Harman emphasized in an earlier paper, 1 what we are introspectively aware of in our experience is its presentational or representational content, not any "mental paint" which bestows this content. I shall refer to all of this as Harman's "phenomenological point." Because we agree on this, we also agree that if his characters George and Mary were spectrum inverted relative to each other, supposing that to be possible, this would have to involve their perceiving the same objects as having different properties, this despite the fact that as normal perceivers they would perceive these objects as having the same colors. And I think we agree that in this case the properties would have to be relational ones, defined or constituted by their relations to the experiences of the subject perceiving them. (shrink)

Even if spectrum inversion of various sorts is possible, spectrum inversion without a difference in representation is not. So spectrum inversion does not pose a challenge for the intentionalist thesis that, necessarily, within a given sense modality, if two experiences are alike with respect to content, they are also alike with respect to their phenomenal character. On the contrary, reflection on variants of standard cases of spectrum inversion provides a strong argument for intentionalism. Depending on one’s views about the possibility (...) of spectrum inversion, the impossibility of spectrum inversion without a difference in representation can also be used as an argument against a variety of reductive theories of mental representation. (shrink)

Critics of wide functionalism have traditionally sought to attack the theory by exposing weaknesses in its account of the qualitative content of experience. Wide functionalist theories of intentional content, however, were spared philosophical scrutiny. I propose that wide functionalist accounts of the intentional content are equally susceptible to attack. I will attempt to demonstrate this by enlisting the functionalist's old foe from the qualia wars - the inverted spectrum hypothesis - in a new way. If the argument is sound, not (...) only will I have shown that the inverted spectrum hypothesis may have more use than philosophical literature recognizes, I will have also exposed a weakness in a dominant philosophical theory: the wide functionalist theory of intentional content. (shrink)

This book maintains that our conception of consciousness and cognition begins with and depends upon a few fundamental errors. Thau elucidates these errors by discussing three important philosophical puzzles - Spectrum Inversion, Frege's Puzzle, and Black-and-White Mary - each of which concerns some aspect of either consciousness or cognition. He argues that it has gone unnoticed that each of these puzzles presents the very same problem and, in bringing this commonality to light, the errors in our natural conception of consciousness (...) and cognition are also reviewed. (shrink)

Most philosophers who have endorsed the idea that there is such a thing as phenomenal content—content that supervenes on phenomenal character—have also endorsed what I call Standard Russellianism. According to Standard Russellianism, phenomenal content is Russellian in nature, and the properties represented by perceptual experiences are mind-independent physical properties. In agreement with Sydney Shoemaker [Shoemaker, S. (1994). Philosophy and Phenomenological Research, 54 249–314], I argue that Standard Russellianism is incompatible with the possibility of spectrum inversion without illusion. One defense of (...) (...) Standard Russellianism is to hold that spectrum inversion without illusion is conceivable but not in fact possible. I argue that this response fails. As a consequence, either phenomenal content is not Russellian, or experiences do not represent mind-independent physical properties. (shrink)

I defend the possibility of a functional account of the intrinsic qualities of sensory experience against the claim that functional characterization can only describe such qualities to the level of isomorphism of relational structures on those qualities. A form sensory holism might be true concerning the phenomenal, and this holism would account for some antifunctionalist intuition evoked by inverted spectrum and absent qualia arguments. Sensory holism is compatible with the correctness of functionalism about the phenomenal.

Sydney Shoemaker offers an account of color perception that attempts to do justice, within a functionalist framework, to the commonsense view that colors are properties of ordinary objects, to the existence of qualia, and to the possibility of spectrum inversions. Shoemaker posits phenomenal properties as dispositional properties of colored objects that explain how there can be intersubjective variation in the experience of a particular color. I argue that his account does not in fact allow for the description of a spectrum (...) inversion scenario, and that it cannot sustain a functionalist relationship between an object's color and its phenomenal properties. Functionalists must, however, come to terms with Shoemaker's recognition that intersubjective spectrum shifts are possible. (shrink)

Palmer=s main intuition pump, the Acolor machine, @ greatly underestimates the complexity of a system isomorphic in color experience to humans. The neuroscientific picture of this complexity makes clear that the brain actively produces our experiences by processes that science can investigate, thereby supporting functionalism and leaving no (color) room for a passive observer to witness subisomorphic experiential differences.

Chalmers (The Conscious Mind, Oxford Unversity Press, Oxford 1996) has argued for a form of property dualism on the basis of the concept of a zombie (which is physically identical to normals), and the concept of the inverted spectrum. He asserts that these concepts show that the facts about consciousness, such as experience or qualia, are really further facts about our world, over and above the physical facts. He claims that they are the hard part of the mind-body issue. He (...) also claims that consciousness is a fundamental feature of the world like mass, charge, etc. He says that consciousness does not logically supervene on the physical and all current attempts to assert an identity between consciousness and the physical are just as non-reductive as his dualism. They are simply correlations and are part of the problem of the explanatory gap. In this paper, three examples of strong identities between a sensation or a quale and a physiological process are presented, which overcome these problems. They explain the identity in an a priori manner and they show that consciousness or sensations (Q) logically supervene on the physical (P), in that it is logically impossible to have P and not to have Q. In each case, the sensation was predicted and entailed by the physical. The inverted spectrum problem for consciousness is overcome and explained by a striking asymmetry in colour space. It is concluded that as some physical properties realize some sensations or qualia that human zombies are not metaphysically possible and the explanatory gap is bridged in these cases. Thus, the hard problem is overcome in these instances. (shrink)

Taking the real Newtonian colour circle – and not the one Palmer depicts as Newton's – we don't have to wait 300 years for Palmer to say no to the Lockean aperçu about the inverted spectrum. One of the aims of this historical detour is to show that one's commitment about the “topology” of the colour space greatly affects Palmer's argument.