Color-vision defects constitute a spectrum of disorders with varying degrees and types of departure from normal human color vision. One form of color-vision defect is dichromacy; by mixing together only two lights, the dichromat can match any light, unlike normal trichromatic humans, who need to mix three. In a philosophical context, our titular question may be taken in two ways. First, it can be taken at face value as a question about visible properties of external objects, and second, it may (...) be interpreted as the more intangible question of “what it’s like” to be color-blind. (shrink)

This article is a summary of two chapters of a book published in French in 1997, entitled Comment L'esprit vient aux Bêtes, Paris, Gallimard. The core idea is that the crucial distinction between internal and external states, often used uncritically by theorists of intentionality, needs to be made on a non-circular basis. The proposal is that objectivity - the capacity to reidentify individuals as the same across places and times depends on the capacity to extract spatial crossmodal invariants, which in (...) turn presupposes a capacity to (re)calibrate perceptual inputs across modalities in a principled way. (shrink)

University of Connecticut Storrs, CT 06279-2054. Recent versions of objectivism can reply to the argument from metamers. The deeper rift between subjectivists and objectivists lies in the question of how to explain the structure of qualitative similarities among the colors. Subjectivism grounded in this fashion can answer the circularity objection raised by Dedrick. It endorses skepticism about the claim that there is some one property of objects that it is the function of color vision to detect. Color vision may enable (...) us to detect differences in spectral composition without granting us the capacity to detect identities. (shrink)

Primary quality theories of color claim that colors are intrinsic, objective, mind-independent properties of external objects — that colors, like size and shape, are examples of the sort of properties moderns such as Boyle and Locke called primary qualities of body.¹ Primary quality theories have long been seen as one of the main philosophical options for understanding the nature of color.

A serious crisis is identified in theories of neurocomputation, marked by a persistent disparity between the phenomenological or experiential account of visual perception and the neurophysiological level of description of the visual system. In particular, conventional concepts of neural processing offer no explanation for the holistic global aspects of perception identified by Gestalt theory. The problem is paradigmatic and can be traced to contemporary concepts of the functional role of the neural cell, known as the Neuron Doctrine. In the absence (...) of an alternative neurophysiologically plausible model, I propose a perceptual modeling approach, to model the percept as experienced subjectively, rather than modeling the objective neurophysiological state of the visual system that supposedly subserves that experience. A Gestalt Bubble model is presented to demonstrate how the elusive Gestalt principles of emergence, reification, and invariance can be expressed in a quantitative model of the subjective experience of visual consciousness. That model in turn reveals a unique computational strategy underlying visual processing, which is unlike any algorithm devised by man, and certainly unlike the atomistic feed-forward model of neurocomputation offered by the Neuron Doctrine paradigm. The perceptual modeling approach reveals the primary function of perception as that of generating a fully spatial virtual-reality replica of the external world in an internal representation. The common objections to this picture-in-the-head concept of perceptual representation are shown to be ill founded. Key Words: brain-anchored; Cartesian theatre; consciousness; emergence; extrinsic constraints; filling-in; Gestalt; homunculus; indirect realism; intrinsic constraints; invariance; isomorphism; multistability; objective phenomenology; perceptual modeling; perspective; phenomenology; psychophysical parallelism; psychophysical postulate; qualia; reification; representationalism; structural coherence. (shrink)

The Hurvich-Jameson (H-J) opponent-process network offers a familiar account of the empirical structure of the phenomenological color space for humans, an account with a number of predictive and explanatory virtues. Its successes form the bulk of the existing reasons for suggesting a strict identity between our various color sensations on the one hand, and our various coding vectors across the color-opponent neurons in our primary visual pathways on the other. But anti-reductionists standardly complain that the systematic parallels discovered by the (...) H-J network are just empirical correspondences, constructed post facto, with no predictive or explanatory purchase on the intrinsic characters of qualia proper. The present paper disputes that complaint, by illustrating that the H-J model yields some novel and unappreciated predictions, and some novel and unappreciated explanations, concerning the qualitative characters of a considerable variety of color sensations possible for human experience, color sensations that normal people have almost certainly never had before, color sensations whose accurate descriptions in ordinary language appear semantically ill-formed or even self-contradictory. Specifically, these "impossible" color sensations are activation-vectors (across our opponent-process neurons) that lie inside the space of neuronally possible activation-vectors, but outside the central 'color spindle' that confines the familiar range of sensations for possible objective colors. These extra-spindle chimerical-color sensations correspond to no reflective color that you will ever see objectively displayed on a physical object. But the H-J model both predicts their existence and explains their highly anomalous qualitative characters in some detail. It also suggests how to produce these rogue sensations by a simple procedure made available in the latter half of this paper. The relevant color plates will allow you to savor these sensations for yourself. (shrink)

To make progress on the problem of consciousness, we have to confront it directly. In this paper, I first isolate the truly hard part of the problem, separating it from more tractable parts and giving an account of why it is so difficult to explain. I critique some recent work that uses reductive methods to address consciousness, and argue that such methods inevitably fail to come to grips with the hardest part of the problem. Once this failure is recognized, the (...) door to further progress is opened. In the second half of the paper, I argue that if we move to a new kind of nonreductive explanation, a naturalistic account of consciousness can be given. I put forward my own candidate for such an account: a nonreductive theory based on principles of structural coherence and organizational invariance, and a double-aspect theory of information. (shrink)

Edgington has proposed a solution to the sorites paradox in terms of ‘verities’, which she defines as degrees of closeness to clear truth. Central to her solution is the assumption that verities are formally probabilities. She is silent on what verities might derive from and on why they should be probabilities. This paper places Edgington’s solution in the framework of a spatial approach to conceptualization, arguing that verities may be conceived of as deriving from how our concepts relate to each (...) other. Building on work by Kamp and Partee, this paper further shows how verities, thus conceived of, may plausibly be assumed to have probabilistic structure. The new interpretation of verities is argued to also help answer the question of what the verities of indicative conditionals are, a question which Edgington leaves open. Finally, the question of how to accommodate higher-order vagueness, given this interpretation, is addressed. (shrink)

Are colors relational or non-relational properties of their bearers? Is red a property that is instantiated by all and only the objects with a certain intrinsic (/non-relational) nature? Or does an object with a particular intrinsic (/non-relational) nature count as red only in virtue of standing in certain relations - for example, only when it looks a certain way to a certain perceiver, or only in certain circumstances of observation? In this paper I shall argue for the view that color (...) properties are relational (henceforth, relationalism), and against the view that colors are not relational (henceforth, anti- or non-relationalism). (shrink)

Anything is similar to anything, provided the respects of similarity are allowed to be gerrymandered or gruesome, as Goodman observed.2 But similarity in non-gruesome or—as I shall say—genuine respects is much less ecumenical. Colors, it seems, provide a compelling illustration of the distinction as applied to similarities among properties.3 For instance, in innumerable gruesome respects, blue is more similar to yellow than to purple. But in a genuine respect, blue is more similar to purple than to yellow (genuinely more similar, (...) as I shall sometimes put it). (shrink)

Representationalism holds that a perceptual experience's qualitative character is identical with certain of its representational properties. To date, most representationalists endorse atomistic theories of perceptual content, according to which an experience's content, and thus character, does not depend on its relations to other experiences. David Rosenthal, by contrast, proposes a view that is naturally construed as a version of representationalism on which experiences’ relations to one another determine their contents and characters. I offer here a new defense of this holistic (...) representationalism, arguing that some objections to atomistic views are best interpreted as supporting it. (shrink)

Seattle rain smelled different from New Orleans rain…. New Orleans rain smelled of sulfur and hibiscus, trumpet metal, thunder, and sweat. Seattle rain, the widespread rain of the Great Northwest, smelled of green ice and sumi ink, of geology and silence and minnow breath.— Tom Robbins, Jitterbug PerfumeMuch of the philosophical literature on perception has focused on vision. This is not surprising, given that vision holds for us a certain prestige. Our visual experience is incredibly rich, offering up a mosaic (...) of apparent three-dimensional objects. For this reason, it is commonplace to suppose that visual experience is world-directed, with the view taking its most popular form in the representational, or content, view. World-directed views contrast with what we might call subjectivist views — views according to which experiences are raw feels or mere sensations. (shrink)

This paper critiques the representationalist account of qualia, focussing on the Representational Naturalism presented by Fred Dretske in Naturalizing the Mind. After laying out Dretskes theory of qualia and making clear its externalist consequences, I argue that Dretskes definition is either too liberal or runs into problems defending its requirements, in particular naturalness and mentalness. I go on to show that Dretskes account of qualia falls foul of the argument from misperception in such a way that Dretske must either admit (...) that his kind of qualia have nothing at all to do with what mental life subjectively feels like, or that veridical perception involves qualia and misperception does not. (shrink)

The question of the constituting nature of colour is largely open. The old dispute between colour objectivism and colour subjectivism is still relevant. The former has defended itself against accusations of not being able to explain colour structures, while the latter view has received criticism for not being able to provide a plausible theory of the location of colours. By weakening the notion of physical categories, making some of them perceiver-depended, colour objectivists have managed to overcome at least some of (...) the previous accusations. However, the arguments based on Crane’s and Piantanida’s findings of the existence of binary colours like greenish-red and yellowish-blue, indicate the inadequacy of colour objectivism. Consequently, we have colours but our theories of them are false. (shrink)

Qualitative-consciousness arises at the sensory level of olfactory processing and pervades our experience of smells to the extent that qualitative character is maintained whenever we are aware of undergoing an olfactory experience. Building upon the distinction between Access and Phenomenal Consciousness the paper offers a nuanced distinction between Awareness and Qualitative-consciousness that is applicable to olfaction in a manner that is conceptual precise and empirically viable. Mounting empirical research is offered substantiating the applicability of the distinction to olfaction and showing (...) that olfactory qualitative-consciousness can occur without awareness, but any olfactory state that we are aware of being in is always qualitative. Evidence that olfactory sensory states have a qualitatively character in the absence of awareness derives from research on mate selection, the selection of social preference for social interaction and acquaintances, as well as the role of olfactory deficits in causing affective disorders. Furthermore, the conservation of secondary processing measures of olfactory valence during olfactory imagery experiments provides verification that olfactory awareness is always qualitatively conscious—all olfactory consciousness smells phenomenal. (shrink)

One popular materialist response to the explanatory gap identifies phenomenal concepts with type-demonstrative concepts. This kind of response, however, faces a serious challenge: that our phenomenal concepts seem to provide a richer characterization of their referents than just the demonstrative characterization of 'that quality'. In this paper, I develop a materialist account that beefs up the contents of phenomenal concepts while retaining the idea that these contents contain demonstrative elements. I illustrate this account by focusing on our phenomenal concepts of (...) phenomenal colour. The phenomenal colours stand in a similarity space relative to one another in virtue of being complex qualities—qualities that contain saturation, lightness, and various aspects of hue as component elements. Our phenomenal concepts, in turn, provide a demonstrative characterization of each of these component elements as well as a description of how much of that element is present in a given phenomenal colour. The result is an account where phenomenal concepts contain demonstrative elements and yet provide a significantly richer characterization of the intrinsic nature of their referents than just 'that quality'. (shrink)

I argue that phenomenal externalism is preferable to phenomenal internalism on the basis of externalism's explanatory power with respect to qualitative character. I argue that external qualities, namely, external physical properties that are qualitative independent of consciousness, are necessary to explain qualitative character, and that phenomenal externalism is best understood as accepting external qualities while phenomenal internalism is best understood as rejecting them. I build support for the claim that external qualities are necessary to explain qualitative character on the basis (...) of a model of color perception as a certain sort of information filter by which perceivers gain access to external qualities. (shrink)

In this paper I explicate a technique which can be used to make subtle relational features of experience more evident to awareness. Results of this method could be employed to diffuse one intuition that drives the common critique of functionalist-information theoretic accounts of mind that "qualia" cannot be exhaustively characterized in information theoretic-functional terms. An intuition that commonly grounds this critique is that the qualitative aspects of experience do not entirely appear in consciousness as informational-functional structures. The first section of (...) the paper is a schematic overview of nature of the qualitative and the problem that qualia are taken to create for information theoretic-functionalist theories of mind. §2 contains a précis of the concept of different levels of functional scale in mental activity that was developed by Armstrong and the Churchlands and that is needed to interpret (possible) results of the proposed experiment. In §3, I outline a method whereby analogies would be generated between purely relational forms, structures, configurations, etc. and purely qualitative aspects of experience. These analogies would be created by subjects through forced choice selection of presented images of structures that "most resembled" a pure quality. Repeated choices would then be shaped by a genetic program into the structural configuration that "most resembled" the pure quality. The final section of the paper explores how consistent, reliable results from the experiment would make information-theoretic functionalism more intuitively plausible in spite of the "fact" that the qualitative aspects of experience do not immediately appear as entirely relational/structural. (shrink)

Quality-space theory (QST) explains the nature of the mental qualities distinctive of perceptual states by appeal to their role in perceiving. QST is typically described in terms of the mental qualities that pertain to color. Here we apply QST to the olfactory modalities. Olfaction is in various respects more complex than vision, and so provides a useful test case for QST. To determine whether QST can deal with the challenges olfaction presents, we show how a quality space (QS) could be (...) constructed relying on olfactory perceptible properties and the olfactory mental qualities then defined by appeal to that QS of olfactory perceptible properties. We also consider how to delimit the olfactory QS from other modalities. We further apply QST to the role that experience plays in refining our olfactory discriminative abilities and the occurrence of olfactory mental qualities in non-conscious olfactory states. QST is shown to be fully applicable to and useful for understanding the complex domain of olfaction. (shrink)

I argue against a class of philosophical views of color perception, especially insofar as such views posit the existence of color sensations. I argue against the need to posit such nonconceptual mental intermediaries between the stimulus and the eventual conceptualized perceptual judgment. Central to my arguments are considerations of certain color illusions. Such illusions are best explained by reference to high-level, conceptualized knowledge concerning, for example, object identity, likely lighting conditions, and material composition of the distal stimulus. Such explanations obviate (...) the need to appeal to nonconceputal mental links in the causal chains eventuating in conceptualized color discriminations. (shrink)

Contrary to certain rumours, the mind-body problem is alive and well. So argues Joseph Levine in Purple Haze: The Puzzle of Consciousness . The main argument is simple enough. Considerations of causal efficacy require us to accept that subjective experiential, or 'phenomenal', properties are realized in basic non-mental, probably physical properties. But no amount of knowledge of those physical properties will allow us conclusively to deduce facts about the existence and nature of phenomenal properties. This failure of deducibility constitutes an (...) explanatory problem - an explanatory gap - but does not imply the existence of immaterial mental properties. Levine introduced this notion of the explanatory gap almost two decades ago. Purple Haze allows Levine to situate the explanatory gap in a broader philosophical context. He engages with those who hold that the explanatory gap is best understood as implying anti-materialist metaphysical conclusions. But he also seeks to distance himself from contemporary naturalistic philosophical theorizing about consciousness by arguing that reductive and eliminative theories of consciousness all fail. Levine's work is best seen as an attempt to firmly establish a definite status for the mind-body problem, i.e. that the mind-body problem is a real, substantive epistemological problem but emphatically not a metaphysical one. Because Levine's work is tightly focused upon contemporary Anglophone analytic philosophy of mind, there is little discussion of the broader conceptual background to the mind-body problem. My aim here is to place Levine's work in a broader conceptual context. In particular, I focus on the relationship between consciousness and intentionality in the belief that doing so will allow us better to understand and evaluate Levine's arguments and their place in contemporary theorizing about mentality and consciousness. (shrink)