The Inverted Spectrum
Philosophy papers
Austen Clark (1985). Spectrum inversion and the color solid.
(NO ABSTRACT)
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.
Ned Block (1990). Inverted Earth. Philosophical Perspectives 4:53-79.
(NO ABSTRACT)
Inverted Earth = (converse of traditional IS) inverted intentional content and function, same qualia. That is, the same qualia represent different things:
“If I am right about this case, the distinction between the intentional and qualitative content of experience is vindicated, and the functionalist theory of qualitative content is refuted” (pdf 11, p 62)
Inverted Earth diff from Earth in that (1) everything actually has complementary colour (B-Y, R-G). (2) Vocab same as ours (.’. inverted for their own colours). They see a yellow sky, but say blue. In other words, our behaviour and qualia are indistinguishable, but the intentional content is inverted.
Now an Earthling gets inversion lenses inserted into eyes, and transported to Inverted Earth. Qualia remain the same. You notice no difference. Brain states same. But the representation different; your intentional content (what your experience is about) is about the stuff back home. That's what your language was rooted in, so that's what you're referring to. Thus, you have different intentional content than Inverted Earthlings (pdf 13, p 64). This means that your utterances & thoughts are WRONG, because they have the wrong intentional content--they're not referring to the properties of the Inverted Earth.
Crucially, after 50 years of living on Inverted Earth, your language adapts (your words start to refer to) Inverted Earth world. Now the Inverted Earth scenario is complete: your intentions / functions have inverted, invert to match those of the natives' of Inverted Earth, while your qualia remain the same. Thus, we have a complete inverted spectrum with no detectable behavioural differences, but an inversion of reference / function. Functionalism is refuted.
Justin Broackes Black and White and the Inverted Spectrum The Philosophical Quarterly, Vol. 57, No. 227 (Apr., 2007), pp. 161-175
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.
Arg:
1. Y&B and R&G inversion requires inversion of black & white (B&W)
2. But B&W can’t be inverted because their function in visibility precludes it. (p. 170)
.’. 3. Y&B and R&G can’t be inverted.
Campbell, N. (2000). Physicalism, Qualia Inversion, and Affective States Synthese, 124(2), 239-255.
I argue that the inverted spectrum hypothesis is not a possibility we should take seriously. The principle reason is that if someone's qualia were inverted in the specified manner there is reason to believe the phenomenal difference would manifest itself in behaviour. This is so for two reasons. First, I suggest that qualia, including phenomenal colours, are partly constituted by an affective component which would be inverted along with the connected qualia. The resulting affective inversions will, given the intimate connections that exist between emotions and behaviour, likely manifest themselves in behaviour, in which case the underlying phenomenal differences can be functionally captured. Second, I argue that other sense modalities lack the structural features necessary for undetectable inversion which, because of their analogy with colour qualia, weakens the plausibility of such an inversion in the original case of vision.
Cohen, J. (2001). Color, Content, & Fred: On a Proposed Reductio of the Inverted Spectrum Hypothesis. Philosophical Studies: An International Journal for Philosophy in the Analytic Tradition, 103, 121-144.
The inverted spectrum hypothesis holds that there might possibly be someone whose linguistic and non-linguistic behavior is just like ours, but whose color experiences are systematically inverted: what he experiences when he looks at red objects is what we experience when we look at green objects and vice versa. Recently, Byrne and Hilbert have argued that such cases are impossible (Byrne and Hilbert, 1997a, pp. 268-272). This strategy is truly bold. After all, inverted spectrum cases have seemed possible to very many philosophers with otherwise divergent views, and even young children. Byrne and Hilbert challenge all this, claiming that the widespread intuitions are incoherent. I, too, have devoted sleepless nights to inverted spectra, so I would be delighted if Byrne's and Hilbert's strategy succeeded. Unfortunately, I don't think it can. In this paper, I shall explain why.Cohen must argue against IS... But not the way that Byrne & Hilbert do.
David J. Cole (1990). Functionalism and Inverted Spectra. Synthese 82 (2):207-22.
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.
Dennett, D. (1991). Consciousness Explained. Little, Brown and Co.(A Philosophical Fantasy: Inverted Qualia, p. 389 – 398)
“If there are no qualia over and above the sum total of dispositions to react, the idea of holding the qualia constant while adjusting the dispositions is self-contradictory.” (p. 398)
The intuition that qualia would remain the same is thanks to the tenacious, mistaken intuition of a Cartesian Theatre.
Terence E. Horgan (1984). Functionalism, Qualia, and the Inverted Spectrum. Philosophy and Phenomenological Research 44 (June):453-69.
(NO ABSTRACT)
Horgan thinks Inverted spectrum is intelligible.
Functionalism is the doctrine that every mental state-type may be fully defined by means of its typical causal connections to sensory stimulation, behavior, and other mental state-types similarly defined. Some philosophers, myself included, believe that although functionalism is plausible as regards certain aspects of mentality, nevertheless there is one aspect that is incapable, in principle, of being analyzed functionally: viz., the qualitative, or phenomenal, content of our mental states - i.e., what it is like to undergo these states. What we mean by the notion of qualitative content, and why we think that this aspect of mentality cannot be accommodated by functionalism, are nicely summarized by Jerry Fodor:
Try to imagine looking at a blank wall through a red filter. Now change the filter to a green one and leave everything else exactly the way it was. Something about the character of your experience changes when the filter does, and it is this kind of thing that philosophers call qualitative content....
The reason qualitative content is a problem for functionalism is straightforward. Functionalism is committed to defining mental states in terms of their causes and effects. It seems, however, as if two mental states could have all the same causal relations and yet could differ in their qualitative content. Let me illustrate this with the classic puzzle of the inverted spectrum.
Heuveln, Dietrich, & Oshima (1998). Let's Dance! The Equivodation in Chalmer's Dancing Qualia Arg. Minds & Machines, 8: 237-249.
David Chalmers‘ dancing qualia argument is intended to show that phenomenal experiences, or qualia, are organizational invariants. The dancing qualia argument is a reductio ad absurdum, attempting to demonstrate that holding an alternative position, such as the famous inverted spectrum argument, leads one to an implausible position about the relation between consciousness and cognition. In this paper, we argue that Chalmers‘ dancing qualia argument fails to establish the plausibility of qualia being organizational invariants. Even stronger, we will argue that the gap in the argument cannot be closed.
David R. Hilbert & Mark Eli Kalderon (2000). Color and the Inverted Spectrum. In Steven Davis (ed.), Vancouver Studies in Cognitive Science. New York: Oxford University Press.
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).
Let Nonvert be a normal subject—Nonvert enjoys blue-feeling experiences when looking at violets and yellow-feeling experiences when looking at marigolds. Invert, however, is phenomenologically inverted in the way that Locke describes. Invert has yellow-feeling experiences when looking at violets and blue-feeling experiences when looking at marigolds. In normal subjects blue-feeling and blue-representing experiences coincide. Consider now Invert’s visual experience of a violet. It is a yellow-feeling experience, but is it also yellow-representing? Or are Invert’s yellow-feeling experiences, in fact, blue-representing? There are at least four lines of thought that suggest that Invert’s yellow-feeling experiences are blue-representing.
J. Harvey (1979): Systematic transposition of colours, Australasian Journal of Philosophy, 57:3, 211-219
The question is sometimes raised whether one person can ever be sure that he sees the same colours as some other person if they both make the same discriminations between objects, on the basis of colour, for traditionally it is claimed that a 'systematic transposition' of colours between two people is logically impossible to detect. On the other hand, on this traditional view it is logically possible to detect a difference in colour-vision between two people if the difference is non-systematic, or is 'overlapping' as I shall call it. These two claims I shall refer to as the Transposition Doctrine. In this paper I shall argue that it is logically possible to detect both kinds of transposition of colours, and that the doctrine is therefore mistaken. And I shall argue that rejecting the central claim of my argument renders the key-concepts of the doctrine incoherent.
Bredo C. Johnsen (1993). Intelligibility of Spectrum Inversion. Canadian Journal of Philosophy, Vol. 23, No. 4 (Dec., 1993), pp. 631-636
Johnsen defends an extreme Inversion spectrum hypothesis (EISH) from Christopher Peacock’s attack.
Christopher Peacocke has recently made an important and insightful effort to fashion a non-verificationist method for distinguishing sense from nonsense (or, as he puts it, genuine from spurious hypotheses).1 The argument is subtle and complex, and varies somewhat with each of his three target 'spurious hypotheses': that if a perfect fission of one person into two were to occur, one and only one of the resulting persons would be identical with the original; that another person's visual experience can be qualitatively different from your own when you are both seeing the same object, even though your relevant brain states are physically identical and so are your environmental conditions...
However, my purpose here is not to engage in a comprehensive evaluation of Peacocke's project; it is rather to defend the extreme inverted spectrum hypothesis (henceforth EISH) against his attack. I shall argue not only that his argument against EISH fails, but that he is himself independently committed to its intelligibility...
Eric Marcus (2006). Intentionalism and the Imaginability of the Inverted Spectrum. Philosophical Quarterly 56 (224):321-339.
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 debated 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.
Marcus is against IS: he defends intentionalism against IS, as IS is supposed to show intentionalism to be false.
Shoemaker - 1982 - The Inverted Spectrum
(NO ABSTRACT)
If intrasubjective IS is possible, then intersubjective IS is also possible (Shoemaker 1982, p. 359).
The IS is implausible because it’s not parsimonious (evolutionarily).
Brad J. Thompson (2008). Representationalism and the Conceivability of Inverted Spectra. Synthese 160 (2):203-213.
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.
Michael Tye (1993). Qualia, Content, and the Inverted Spectrum. Noûs 27 (2):159-183.
This article has no associated abstract.
Jeff Speaks (2011). Spectrum Inversion Without a Difference in Representation is Impossible. Philosophical Studies 156 (3):339-361.
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.
NEUROPHILOSOPHY
Byrne, A., & Hilbert, D. R. (2003). Colour Realism & Colour Science. Behavioral and Brain Sciences 26(1), 3-21.
The target article is an attempt to make some progress on the problem of color realism. Are objects colored? And what is the nature of the color properties? We defend the view that physical objects (for instance, tomatoes, radishes, and rubies) are colored, and that colors are physical properties, specifically, types of reflectance. This is probably a minority opinion, at least among color scientists. Textbooks frequently claim that physical objects are not colored, and that the colors are “subjective” or “in the mind.” The article has two other purposes: First, to introduce an interdisciplinary audience to some distinctively philosophical tools that are useful in tackling the problem of color realism and, second, to clarify the various positions and central arguments in the debate. The first part explains the problem of color realism and makes some useful distinctions. These distinctions are then used to expose various confusions that often prevent people from seeing that the issues are genuine and difficult, and that the problem of color realism ought to be of interest to anyone working in the field of color science. The second part explains the various leading answers to the problem of color realism, and (briefly) argues that all views other than our own have serious difficulties or are unmotivated. The third part explains and motivates our own view, that colors are types of reflectances and defends it against objections made in the recent literature that are often taken as fatal.
Martine Nida-Rumelin (1996). Pseudonormal Vision: An Actual Case of Qualia Inversion? Philosophical Studies 82 (2):145-57.
Is it possible that a person who behaves just like you and me in normal life situations and applies colour words to objects just as we do and makes the same colour discriminations and colour similarity judgements that we make, see green where we see red and red where we see green? Many philosophers assert that the description of such a case is somehow incoherent. Often the motivation for this assertion is "that they suspect that admitting that claim [the possibility of such a case] will put one on a slippery slope which will eventually land one in skepticism about other minds." Theories about the physiological basis of colour vision deficiencies together with theories about the genetics of colour vision deficiencies lead to the prediction that some people are 'pseudonormal' (according to an estimation of Piantanida (1974) this occurs in around 14 of 10 000 males). Pseudonormal people "would be expected to have normal colour vision except that the sensations of red and green would be reversed - something that would be difficult, if not impossible, to prove... No hypotheses accepted or seriously considered in colour vision science should be regarded according to a philosophical theory to be either incoherent or unstatable or false.
Neuroscience
Robert M. Boynton "Human Color Vision", New York et al. 1979, Holt Rinehart and Winston, p. 351-358
(No abstract) (Cites Piantanida’s work (below), and there I assume builds on it.)
Piantanida, T. P., 1974. A replacement model of X-linked recessive color vision defects. In Annals of Human Genetics 37: 393-404
One of the many unexplained aspects of defective colour vision is the dominance hierarchy within the allelic series at each colour vision locus. Since the work of Franceschetti (1928, 1949) it has been known that the dominance order favours less defective forms of colour vision, but until recently, too little was known about the causes of anomalous trichromacy to even speculate about the manner in which the expression of the mutant alleles was either repressed or compensated by the allele for normal colour vision in the heterozygote. However, the recent reports by Rushton, Powell & White (1973a, b ) and Piantanida & Sperling (1973a, 6) have provided psychophysical evidence that may help explain the dominance hierarchy. The findings of each of these groups of researchers indicate that the anomalous trichromacies are due to the replacement of one of the normal photopigments by one which has an abnormal absorption spectrum. In the simple protanomalous trichromat, the normal red-sensitive photopigment, erythrolabe (Rushton, 1965), has been replaced by an abnormal photopigment, protanolabe (Rushton et al. 1973a, b ) , and in the simple deuteranomalous trichromat, the green-sensitive photopigment, chlorolabe (Rushton, 1963), has been replaced by the abnormal photopigment deutanolabe (Rushton et al. 1973a, b ) . The spectral region of maximum absorption of both abnormal photopigments is displaced in the wavelength dimension toward the absorption peak of the remaining red/green-sensitive photopigment. Piantanida & Sperling (1973a, b ) reported that the peak absorption of protanolabe was probably near 545nm., the peak of the spectral sensitivity curve of violet-adapted protanomalous trichromats. Thus, the absorption peak of protanolabe is quite close to the 535nm. absorption peak of chlorolabe. They also reported that the sensitivity peak of violet-plus-red-adapted deuteranomalous trichromats, which they interpreted as the absorption peak of deutanolabe, was near 560 nm.
J Pokorny, VC Smith (1982) New observations concerning red–green color defects
Color Research & Application. J. Opt. Soc. Am. 67(9), p. 1196-1209.
The spectral sensitivity of the visual photopigments, the interobserver variability in color judgments, and the spectral locus of unique yellow provide three major problems for accounts of X-chromosomal-linked anomalous trichromacy. According to the single-pigment hypothesis, the primary defect in anomalous trichromacy is a wavelength shift in the peak sensitivity of one of the three visual photopigments. We show that this shift results in reduction of the anomalous trichromat's r-g opponent chromatic channel. The distribution of response variability in Rayleigh equation match widths due.4o factors other than the spectral characteristics of the photopigments is similar in normal and anomalous trichromats. When normal and anomalous trichromats make hue estimations of sets of stimuli designed to contain similar chromatic information, their judgments show similar variability. Calculation of the r-g opponent chromatic channel can provide correct predictions of the spectral loci for unique yellow for anomalous trichromats.
22 abstracts