How should we characterize the nature of perceptual experience? Some theorists claim that colour experiences, to take an example of perceptual experiences, have both intentional properties and properties called 'colour qualia', namely, mental qualitative properties which are what it is like to be conscious of colour. Since proponents of colour qualia hold that these mental properties cannot be explained in terms of causal relations, this position is in opposition to a functionalist characterization of colour experience.

C. L. Hardin led a recent development in the philosophical literature on color in which research from visual science is used to argue that colors are not properties of physical objects, but rather are mental processes. I defend J. J. C. Smart's physicalism, which claims that colors are physical properties of objects, against this attack. Assuming that every object has a single veridical (that is, nonillusory) color, it seems that physicalism must give a specification of veridical color in terms natural (...) to physics, independently of our interests. Hardin argues that since physicalism doesn't give us any such specification of veridical color, this view is false. However, this argument assumes a mistaken account of veridical color. I show physicalism can appeal to an alternative account, according to which veridical color is characterized in terms of favored conditions of perceptual access, independently of any specification of the physical nature of color. (shrink)

The problem of the nature of color is typically put in terms of the following question about the intentional content of visual experiences: what’s the nature of the property we attribute to physical objects in virtue of our visual experiences of color? This problem has proven to be tenacious largely because it’s not clear what the constraints are for an answer. With no clarity about constraints, the proposed solutions range widely, the most common dividing into subjectivist views which hold that (...) attributed colors are mental properties or mental events} and a variety of realist views, which hold that colors are properties of physical objects. These realist views, in turn, divide into views that hold that attributed colors are dispositions of physical objects to produce color experiences (dispositionalism),° nondispositional relations between objects and perceivers (the relational view)," physical properties of physical objects (physicalism),‘ or sui generis properties of physical objects (primitivism and impressionism).‘ I’ll examine a proposed constraint which Mark Johnston (1992) calls Revelation. According to Revelation, the appearance of color in our ordinary visual experience provides us with unqualified access to the nature of color. While every proposal about the nature of color must take a stand on how the.. (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)

Color subjectivism is the view that color properties are mental properties of our visual sensations, perhaps identical with properties of neural states, and that nothing except visual sensations and other mental states exhibits color properties. Color phys- icalism, by contrast, holds that colors are exclusively properties of visible physical objects and processes.

The explanatory gap and theknowledge argument are rooted in the conflationof propositional and phenomenal knowledge. Thebasic knowledge argument is based on theconsideration that ``physical information'' aboutthe nervous system is unable to provide theknowledge of a ``color experience'' . The implication is that physicalism isincomplete or false because it leaves somethingunexplained. The problem with Jackson'sargument is that physical information has theform of highly symbolic propositional knowledgewhereas phenomenal knowledge consists in innateneurophysiological processes. In addition totheir fundamental epistemological differences,clinical, anatomical, pathological and brainimaging (...) studies demonstrate that phenomenal andpropositional knowledge are fundamentallydifferent neurobiological processes. Propositional knowledge is phylogeneticallynew, highly symbolic, culturally acquired,exclusively human and expressible in differentnatural and artificial languages. By contrast,phenomenal knowledge consists inqualitative experiences and phenomenal conceptsthat provide an internal, language-independentreference to the properties of objects and theneeds of the organism. Language andpropositional knowledge are exclusively humanattributes implemented in specific regions ofthe dominant hemisphere. This contrastssharply with the phylogenicallysensory areas that are common to animals andhumans, which implement qualitativeexperiences. Experiences are hard-wiredneurobiological processes that can neither betransmitted nor re-created through thesymbolism of propositions. Thus, I concludethat the fallacy in the explanatory gap and inthe knowledge argument is a fallacy ofequivocation that results from ignoringfundamental neurobiological differences betweenphenomenal and propositional knowledge. (shrink)

In this paper I consider the relationship between the spatial properties of visual perceptual experience and the sense-datum inference. I argue that the sense datum inference should be accepted if spatial properties are not merely intentionally present in such experiences. This result serves to underline the seriousness of the difficulties that are presented to direct realism by a particular class of illusory spatial experiences based on the geometry of visual perceptual experience. In light of these considerations I argue that it (...) is a constraint on direct realism that the underlying spatial character of visual perceptual experiences must be the same as that of the physical world. (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)

The philosophical debate over the nature of color has been governed by what we have learnt from color vision science and what color phenomenology suggests to us. It is usually thought that color eliminativism, which maintains that physical objects do not have any properties that can be identified with colors, can account for the former but not the latter. After all, what could be more obvious than the external world to be colored? Here I outline one color eliminativistic response to (...) the objections based on phenomenology. (shrink)

Colors are of philosophical interest for two kinds of reason. One is that colors comprise such a large and important portion of our social, personal and epistemological lives and so a philosophical account of our concepts of color is highly desirable. The second reason is that trying to fit colors into accounts of metaphysics, epistemology and science leads to philosophical problems that are intriguing and hard to resolve. Not surprisingly, these two kinds of reasons are related. The fact that colors (...) are so significant in their own right, makes more pressing the philosophical problems of fitting them into more general metaphysical and epistemological frameworks. (shrink)

This dissertation defends the reliability of first-person methods for studying consciousness, and applies first-person experiments to two philosophical problems: the experience of size and of the self. In chapter 1, I discuss the motivations for taking a first-person approach to consciousness, the background assumptions of the dissertation and some methodological preliminaries. In chapter 2, I address the claim that phenomenal judgements are far less reliable than perceptual judgements (Schwitzgebel, 2011). I argue that the main errors and limitations in making phenomenal (...) judgements are due to domain-general factors, which are shared in the formation of perceptual judgements. Phenomenal judgements may still be statistically less reliable than perceptual judgements, though I provide reasons for thinking that Schwitzgebel (2011) overstates the case for statistical unreliability. I also provide criteria for distinguishing between reliable and unreliable phenomenal judgements, hence defending phenomenal judgements against general introspective scepticism. Having identified the main errors in making phenomenal judgements, in chapter 3, I discuss how first-person experiments can be used to control for these errors. I provide examples, and discuss how they overcome attentional and conceptual errors, minimise biases, and exhibit high intersubjective reliability. In chapter 4, I investigate size experience. I use first-person experiments and empirical findings to argue that distant things looking smaller cannot be explained as an awareness of instantiated objective properties (visual angle or retinal image size). I also discuss how an awareness of uninstantiated objective properties cannot adequately account for the phenomenal character of size experience. This provides support for a subjectivist account of variance in size experience. In chapter 5, I investigate the sense of self. I distinguish between a weak sense of self (for-me-ness) and a strong sense of self in which there is a polarity between subject and object. I use first-person experiments from Douglas Harding to demonstrate an explicit strong sense of self, specifically when I point at where others see my face. I also argue that this sense of self is not explained by inference, thoughts, feelings, imagination nor the viewpoint. Rather, it is part of the structure of experience that I seem to be looking from here. Even if there is a sense of self, there may be no self. The question of chapter 6 is whether there can be a direct experience of the self. I argue that to function as a bearer of experience the subject must be single and lack sensory qualities in itself. I use Harding’s first-person experiments to investigate the visual gap where I cannot see my head. I argue that it conforms to the above criteria, and hence is a candidate for being the subject. This finding, in conjunction with the fact that I seem to be looking from the same location, provides prima facie evidence for the reality of the subject. I hold then that contrary to Hume and most philosophers since, that there can be a direct self-experience, if one knows which direction to attend. (shrink)

The nature of the colors—what they are like, whether they are instantiated by objects or are projected by our minds, whether their nature is revealed to us in color perception, and whether there could be alien colors (e.g. reddish-green)—has been one of the central topics in philosophy for centuries. This entry focuses on the contemporary philosophical debate about the nature of the colors.

In this paper I shall defend a projectivist view of sensory experience. The case I shall focus on is that of color experience. Projectivism has recently been criticized by some authors who claim that it is unintelligible, or at least implausible, and that it makes a severe category mistake. I shall argue that despite some prima facie impressions of implausibility, projectivism can be made intelligible, and plausible, if its details are spelled out in a reasonable way. In addition, projectivism is (...) ubiquitous in human psychology, and certain cases of projection are reasonably viewed as making a category mistake. Viewed from this perspective, sensory projection is just one instance of projectivism, brought about by low-level perceptual processing. Whether sensory projection is one that makes a category mistake is not obvious. However, even if it does, this is perfectly compatible with the evolutionary advantage of sensation and perception. (shrink)

Our understanding of human visual perception generally rests on the assumption that conscious visual states represent the interaction of spatial structures in the environment and our nervous system. This assumption is questioned by circumstances where conscious visual states can be triggered by external stimulation which is not primarily spatially defined. This work discusses psychophysical experiments investigating flicker induced subjective experiences of colour and form. Using the presentation of spatially uniform flicker with a precise temporal resolution it is shown that subjective (...) experiences do not only depend on stimulation frequency, but also on stimulation phase. In addition, the occurrence of one subjective experience appears to be associated with the occurrence of others. The phenomenology of subjective colour and form is further explored and the physiological mechanisms underlying subjective colour are investigated using electroencephalography. While these data indicate that conscious visual experience may be evoked directly by particular variations in the flow of spatially unstructured light over time it may be assumed that the systems reponsible are essentially temporal in character and capable of representing a variety of visual forms and colours, coded in different frequencies or at different phases of the same processing rhythm. (shrink)