Intrapersonal variation due to color contrast effects has been used to argue against the following intuitive propositions about the colors: No object can be more than one determinable or determinate color of the same grade all over at the same time ; external objects are actually colored ; and the colors of objects are mind-independent. In this article, I provide a defense of Incompatibility, Realism, and Objectivism from intrapersonal variation arguments that rely on color contrast (...) effects. I provide a novel, ecumenical response to such arguments according to which typical variants are right, and which respects Incompatibility, Realism, and Objectivism, using the thesis that the colors of objects depend on the colors of objects in their surrounds. (shrink)

In psychophysical experiments, the use of a psychophysical procedure of brightness/darkness cancellation shed light on interactions between spatial arrangement and figure–ground contrast in the perceptual filling in of achromatic and colored surfaces.Achromatic and chromatic Kanizsa squares with varying contrast, contrast polarity, and inducer spacingwere used to test how these factors interact in the perceptual filling in of surface brightness or darkness. The results suggest that the neuronal processing of surfaces with apparent contrast, leading to figure–ground segregation (...) (i.e., perceptual organization), is governed by mechanisms that integrate both luminance contrast and spatial information carried by the inducing stimuli, while discarding information on contrast polarity or color. The findings are discussed in relation to earlier observations on brightness assimilation and contrast. They support theories of nonantagonistic neural mechanisms suppressing local contrast or color signs in brightnessbased figure–ground percepts. Such mechanismsmight be necessary to cancel potentially conflicting polarities in geometricallycomplex visual stimuli so that perceptual filling in resulting in the most plausible representation of figure and ground can be achieved. (shrink)

Poorly saturated colors are closer to a pure grey than strongly saturated ones and, therefore, appear less “colorful”. Color saturation is effectively manipulated in the visual arts for balancing conflicting sensations and moods and for inducing the perception of relative distance in the pictorial plane. While perceptual science has proven quite clearly that the luminance contrast of any hue acts as a self-sufficient cue to relative depth in visual images, the role of color saturation in such figure-ground (...) organization has remained unclear. We presented configurations of colored inducers on grey ‘test’ backgrounds to human observers. Luminance and saturation of the inducers was uniform on each trial, but varied across trials. We ran two separate experimental tasks. In the relative background brightness task, perceptual judgments indicated whether the apparent brightness of the grey test background contrasted with, assimilated to, or appeared equal (no effect) to that of a comparison background with the same luminance contrast. Contrast polarity and its interaction with color saturation affected response proportions for contrast, assimilation and no effect. In the figure-ground task, perceptual judgments indicated whether the inducers appeared to lie in front of, behind, or in the same depth with the background. Strongly saturated inducers produced significantly larger proportions of foreground effects indicating that these inducers stand out as figure against the background. Weakly saturated inducers produced significantly larger proportions of background effects, indicating that these inducers are perceived as lying behind the backgrounds. We infer that color saturation modulates figure-ground organization, both directly by determining relative inducer depth, and indirectly, and in interaction with contrast polarity, by affecting apparent background brightness. The results point towards a hitherto undocumented functional role of color saturation in the genesis of form, and in particular figure-ground percepts in the absence of chromatostereopsis. (shrink)

Back when researchers thought about the various forms that color vision could take, the focus was primarily on the retinal mechanisms. Since that time, research on human color vision has shifted from an interest in retinal mechanisms to cortical color processing. This has allowed color research to provide insight into questions that are not limited to early vision but extend to cognition. Direct cortical connections from higher-level areas to lower-level areas have been found throughout the brain. (...) One of the classic questions in cognitive science is whether perception is influenced, and if so to what extent, by cognition and whether a clear distinction can be drawn between perception and cognition. Since perception is seen as providing justification for our beliefs about properties in the external world, these questions also have metaphysical and epistemological significance. The aim of this paper is to highlight some of the areas where research on color perception can shed new light on questions in the cognitive sciences. A further aim of the paper is to raise some questions about color research that are in dire need of further reflection and investigation. (shrink)

The quantization error in a fixed-size Self-Organizing Map (SOM) with unsupervised winner-take-all learning has previously been used successfully to detect, in minimal computation time, highly meaningful changes across images in medical time series and in time series of satellite images. Here, the functional properties of the quantization error in SOM are explored further to show that the metric is capable of reliably discriminating between the finest differences in local contrast intensities and contrast signs. While this capability of the (...) QE is akin to functional characteristics of a specific class of retinal ganglion cells (the so-called Y-cells) in the visual systems of the primate and the cat, the sensitivity of the QE surpasses the capacity limits of human visual detection. Here, the quantization error in the SOM is found to reliably signal changes in contrast or colour when contrast information is removed from or added to the image, but not when the amount and relative weight of contrast information is constant and only the local spatial position of contrast elements in the pattern changes. While the RGB Mean reflects coarser changes in colour or contrast well enough, the SOM-QE is shown to outperform the RGB Mean in the detection of single-pixel changes in images with up to five million pixels. This could have important implications in the context of unsupervised image learning and computational building block approaches to large sets of image data (big data). (shrink)

Colour has often been supposed to be a subjective property, a property to be analysed orretly in terms of the phenomenological aspects of human expereince. In contrast with subjectivism, an objectivist analysis of color takes color to be a property objects possess in themselves, independently of the character of human perceptual expereince. David Hilbert defends a form of objectivism that identifies color with a physical property of surfaces - their spectral reflectance. This analysis of color (...) is shown to provide a more adequate account of the features of human color vision than its subjectivist rivals. The author's account of colro also recognises that the human perceptual system provides a limited and idiosyncratic picture of the world. These limitations are shown to be consistent with a realist account of colour and to provide the necessary tools for giving an analysis of common sense knowledge of color phenomena. (shrink)

Colour vision plays a foundational explanatory role in the philosophy of colour, and serves as perennial quarry in the wider philosophy of perception. I present two contributions to our understanding of this notion. The first is to develop a constitutive approach to characterizing colour vision. This approach seeks to comprehend the nature of colour vision qua psychological kind, as contrasted with traditional experiential approaches, which prioritize descriptions of our ordinary visual experience of colour. The second contribution is to argue that (...) colour vision does not constitutively involve the ability to see colours, in a natural and categorically committed sense. I argue that two subjects exactly alike in respect of their constitutive colour vision abilities could differ in respect of whether or not they have categorical perception of colour. The argument is supported by thought experiment and dissociations observed in cognitive neuropsychology. The argument also bears connections to recent neo-Whorfian accounts of colour categorization. _1._ Introduction _2._ Colour Vision, Experience, and Natures _3._ The Central Argument _3.1._ Colour constancy and discrimination _3.2._ Dissociating colour vision and categorical perception for colour _4._ Whorf and the View from Cognitive Neuropsychology _5._ Conclusion. (shrink)

Colour relationalism holds that the colours are constituted by relations to subjects. Anti-relationalists have claimed that this view stands in stark contrast to our phenomenally-informed, pre-theoretic intuitions. Is this claim right? Cohen and Nichols’ recent empirical study suggests not, as about half of their participants seemed to be relationalists about colour. Despite Cohen and Nichols’ study, we think that the anti-relationalist’s claim is correct. We explain why there are good reasons to suspect that Cohen and Nichols’ experimental design skewed (...) their results in favour of relationalism. We then run an improved study and find that most of our participants seem to be anti-relationalists. We find some other interesting things too. Our results suggest that the majority of ordinary people find it no less intuitive that colours are objective than that shapes are objective. We also find some evidence that when those with little philosophical training are asked about the colours of objects, their intuitions about colour and shape cases are similar, but when asked about people’s colour ascriptions, their intuitions about colour and shape cases differ. (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.

Colors are sensible qualities. They are qualities that objects are perceived to have. Thus, when Norm, a normal perceiver, perceives a blue bead, the bead is perceived have a certain quality, perceived blueness. `Quality', here, is no mere synonym for property; rather, a quality is a kind of property a qualitative, as opposed to quan• titative, property. (The quantitative is a way of contrasting with the qualitative perhaps not the only way.).

Inter-species variation in colour perception poses a serious problem for the view that colours are mind-independent properties. Given that colour perception varies so drastically across species, which species perceives colours as they really are? In this paper, I argue that all do. Specifically, I argue that members of different species perceive properties that are determinates of different, mutually compatible, determinables. This is an instance of a general selectionist strategy for dealing with cases of perceptual variation. According to selectionist views, objects (...) simultaneously instantiate a plurality of colours, all of them genuinely mind-independent, and subjects select from amongst this plurality which colours they perceive. I contrast selectionist views with relationalist views that deny the mind-independence of colour, and consider some general objections to this strategy. (shrink)

Luminance and color are strong and self-sufficient cues to pictorial depth in visual scenes and images. The present study investigates the conditions Under which luminance or color either strengthens or overrides geometric depth cues. We investigated how luminance contrasts associated with color contrast interact with relative height in the visual field, partial occlusion, and interposition in determining the probability that a given figure is perceived as ‘‘nearer’’ than another. Latencies of ‘‘near’’ responses were analyzed to test (...) for effects of attentional selection. Figures in a pair were supported by luminance contrast or isoluminant color contrast and combined with one of the three geometric cues. The results of Experiment 1 show that luminance contrasts associated with hue, when it does not interact with other hues, produces the same effects as achromatic luminance contrasts: The probability of‘‘near’’ increases with luminance contrast while the latencies for ‘‘near’’ responses decrease. Partial occlusion is found to be a strong enough pictorial cue to support a weaker red luminance contrast. Interposition cues lose out against cues of spatial position and partial occlusion. The results of Experiment 2, with isoluminant displays of varying color contrast, reveal that red color contrast on a light background supported by any of the three geometric cues wins over green or white supported by any of the three geometric cues. On a dark background, red color contrast supported by the interposition cue loses out against green or white color contrast supported by partial occlusion. These findings reveal that color is not an independent depth cue, but is strongly influenced by luminance contrast and stimulus geometry. Systematically shorter response latencies for stronger ‘‘near’’ percepts demonstrate that selective visual attention reliably detects the most likely depth cue combination in a given configuration. (shrink)

Victor Vasarely's (1906–1997) important legacy to the study of human perception is brought to the forefront and discussed. A large part of his impressive work conveys the appearance of striking three-dimensional shapes and structures in a large-scale pictorial plane. Current perception science explains such effects by invoking brain mechanisms for the processing of monocular (2D) depth cues. Here in this study, we illustrate and explain local effects of 2D color and contrast cues on the perceptual organization in terms (...) of figure-ground assignments, i.e. which local surfaces are likely to be seen as “nearer” or “bigger” in the image plane. Paired configurations are embedded in a larger, structurally ambivalent pictorial context inspired by some of Vasarely's creations. The figure-ground effects these configurations produce reveal a significant correlation between perceptual solutions for “nearer” and “bigger” when other geometric depth cues are missing. In consistency with previous findings on similar, albeit simpler visual displays, a specific color may compete with luminance contrast to resolve the planar ambiguity of a complex pattern context at a critical point in the hierarchical resolution of figure-ground uncertainty. The potential role of color temperature in this process is brought forward here. Vasarely intuitively understood and successfully exploited the subtle context effects accounted for in this paper, well before empirical investigation had set out to study and explain them in terms of information processing by the visual brain. (shrink)

This paper resolves a paradox concerning colour constancy. On the one hand, our intuitive, pre-theoretical concept holds that colour constancy involves invariance in the perceived colours of surfaces under changes in illumination. On the other, there is a robust scientific consensus that colour constancy can persist in cerebral achromatopsia, a profound impairment in the ability to perceive colours. The first stage of the solution advocates pluralism about our colour constancy capacities. The second details the close relationship between colour constancy and (...) contrast. The third argues that achromatopsics retain a basic type of colour constancy associated with invariants in contrast processing. The fourth suggests that one person-level, conscious upshot of such processing is the visual awareness of chromatic contrasts ‘at’ the edges of surfaces, implicating the ‘colour for form’ perceptual function. This primitive type of constancy sheds new light on our most basic perceptual capacities, which mark the lower borders of representational mind. (shrink)

What is the relationship between color experience and color? Here, I defend the view that it is semantic: color experience denotes color in a code innately known by the perceiver. This semantic theory contrasts with a variety of theories according to which color is defined as the cause of color experience (in a special set of circumstances). It also contrasts with primary quality theories of color, which treat color as a physical quantity. (...) I argue that the semantic theory better accounts for the kinds of knowledge we have regarding both the color of objects that we see and of the colors themselves. (shrink)

Despite a wealth of data we still have no clear idea what color experiences represent. In fact, color experiences vary with so many factors that it has been claimed that they do not represent anything at all. The primary challenge for any representational account of color experience is to accommodate the various psychophysical results that demonstrate that color appearance depends not only on the spectral nature of the target but also on the spectral, spatial and figural (...) nature of the surround. A number of theorists have proposed that this dependence is an aspect of the visual system's constancy mechanism. However this does not in and of itself tell us what, if anything, is represented in color experience. Ultimately the answer to this question will be informed by one's theory of representational content. I will argue that adopting a molecular scheme of representation enables the development of an account of the represented object of color experience that can do justice to the psychophysical data. (shrink)

The resent paper reviews three phases in the literature on cognition and colour, and also Luria's (1976) observations of the effects that literacy and/or schooling have on colour naming and colour categorization. It is argued that Luria's own interpretation of his findings is partiafly flawed by inconsistency, and by ethnocentric presuppositions concerning mediation and abstraction. A revised interpretation is proposed that draws on Gibson's (1950, 1966) contrast between direct and indirect perceptions. It is suggested that language usage and cultural (...) practices come to exert a joint effect upon the experience of colour by selectively directing attention towards or away from the various perceptible aspects of coloured objects. (shrink)

It remains unclear what is being processed in blindsight in response to faces, colours, shapes, and patterns. This was investigated in two hemianopes with chromatic and achromatic stimuli with sharp or shallow luminance or chromatic contrast boundaries or temporal onsets. Performance was excellent only when stimuli had sharp spatial boundaries. When discrimination between isoluminant coloured Gaussians was good it declined to chance levels if stimulus onset was slow. The ability to discriminate between instantaneously presented colours in the hemianopic field (...) depended on their luminance, indicating that wavelength discrimination totally independent of other stimulus qualities is absent. When presented with narrow-band colours the hemianopes detected a stimulus maximally effective for S-cones but invisible to M- and L-cones, indicating that blindsight is mediated not just by the mid-brain, which receives no S-cone input, or that the rods contribute to blindsight. The results show that only simple stimulus features are processed in blindsight. (shrink)

Cortical color blindness, or cerebral achromatopsia, has been likened by some authors to ''blindsight'' for color or an instance of ''covert'' processing of color. Recently, it has been shown that, although such patients are unable to identify or discriminate hue differences, they nevertheless show a striking ability to process wavelength differences, which can result in preserved sensitivity to chromatic contrast and motion in equiluminant displays. Moreover, visually evoked cortical potentials can still be elicited in response to (...) chromatic stimuli. We suggest that these demonstrations reveal intact residual processes rather than the operation of covert processes, where proficient performance is accompanied by a denial of phenomenal awareness. We sought evidence for such covert processes by conducting appropriate tests on achromatopsic subject M.S. An ''indirect'' test entailing measurement of reaction times for letter identification failed to reveal covert color processes. In contrast, in a forced choice oddity task for color, M.S. was unable to verbally indicate the position of the different color, but was surprisingly adept at making an appropriate eye movement to its location. This ''direct'' test thus revealed the possible covert use of chromatic differences. (shrink)

Colour variation is the fact that what colour physical objects look to have depends on viewing conditions and a perceiver’s visual system. Both Colour Relationalists and Colour Eliminativists regard their analyses of colour variation as central to the justification for their respective views. Yet the analyses are decidedly different. Colour Relationalists assert that most instances of colour variation are veridical and infer from this that colours are relational properties of objects that are partly determined by perceivers. By contrast, Colour (...) Eliminativists assert that colour variation is too unsystematic to ground the claim that many or most instances of colour variation are veridical. From this they infer that objects don’t have colours. I argue that the Eliminativist analysis is superior. On my view, the Relationalist account of veridical colour experience reduces to the assertion that objects have colour simply because they cause perceivers to have colour experiences of them. In this context, I argue, the resulting conception of veridicality is vacuous. More directly, the foundational idea of Eliminativism is the opposite claim: the fact that objects cause perceivers to have colour experiences of them is on its own not sufficient to justify or ground the claim that objects have colour. The Relationalist, I argue, has failed to justify anything stronger than this. In this debate we should thus side with the Eliminativist: objects do not possess colour; they merely cause us to undergo colour experiences. (shrink)

In a recent paper, Gow raised a new and interesting problem for externalist representationalism, the conclusion of which is that its proponents are unable to provide an acceptable account of the phenomenal character of colour hallucination. In contrast to Gow, we do not believe that the problem is particularly severe – indeed, that there is any problem at all. Thus our aim is to defend externalist representationalism against the problem raised by Gow. To this end, we will first reconstruct (...) her reasoning, and then show that it poses no real challenge to externalist representationalism. (shrink)

RÉSUMÉ: Dans «Objectivism and the Evolutionary Value of Colour Vision», Don Dedrick suggère qu'une conception raffinée de la valeur adaptative en matière de vision des couleurs conduit à une explication non objectiviste de la couleur. Le raffinement, en l'occurrence, consiste à prendre en considération le rôle que jouent les processus perceptuels internes, contraints par les exigences de l'adaptation, dans la répartition des couleurs selon les catégories familières de rouge, violet, bleu, etc. L'objectivisme, par contraste, est présenté par Dedrick comme la (...) position selon laquelle les catégories de couleur sont proprement déterminées par des facteurs externes à l'esprit — une thèse qu'il attribue à Mohan Matthen. Mon objectif dans cet article est de souligner que les éléments internalistes de l'explication de Dedrick, qui sont rappelés à la section 1, sont parfaitement compatibles avec l'objectivisme chromatique. Cet objectivisme, cependant, n'est pas la thèse que Dedrick entend mettre en cause. Je distingue, dans la section 2, la version critiquée par Dedrick, que j'appelle «l'objectivisme fort», de «l'objectivisme modéré», qui est la thèse selon laquelle la couleur elle-même est indépendante de l'esprit bien que les catégories de couleur soient déterminées par des facteurs internes. La doctrine principale de l'objectivisme même, selon ce que je soutiens, demeure neutre eu égard aux versions fortes ou modérées. Dans la section 3, cette notion centrale d'objectivisme est réconciliée avec une explication de la vision des couleurs qui fait référence à la valeur adaptative en contexte évolutionnaire. (shrink)

The laws which predict how the perceptual quality of figure-ground can be extracted from the most elementary visual signals were discovered by the Gestaltists, and form an essential part of their movement (see especially Metzger, 1930, and Wertheimer, 1923 translated and re-edited by Lothar Spillmann, 2009 and 2012, respectively). Distinguishing figure from ground is a prerequisite for perception of both form and space (the relative positions, trajectories, and distances of objects in the visual field. The human brain has an astonishing (...) capacity for selecting and combining a few critical visual signals to accurately represent both form and space. (shrink)

A Naive Realist Theory of Colour defends the view that colours are mind-independent properties of things in the environment, that are distinct from properties identified by the physical sciences. This view stands in contrast to the long-standing and wide-spread view amongst philosophers and scientists that colours don't really exist - or at any rate, that if they do exist, then they are radically different from the way that they appear. It is argued that a naive realist theory of colour (...) best explains how colours appear to perceiving subjects, and that this view is not undermined either by reflecting on variations in colour perception between perceivers and across perceptual conditions, or by our modern scientific understanding of the world. A Naive Realist Theory of Colour also illustrates how our understanding of what colours are has far-reaching implications for wider questions about the nature of perceptual experience, the relationship between mind and world, the problem of consciousness, the apparent tension between common sense and scientific representations of the world, and even the very nature and possibility of philosophical inquiry. (shrink)

The thresholds of human observers detecting line targets improve significantly when the targets are presented in a spatial context of collinear inducing stimuli. This phenomenon is referred to as spatial facilitation, and may reflect the output of long-range interactions between cortical feature detectors. Spatial facilitation has thus far been observed with luminance-defined, achromatic stimuli on achromatic backgrounds. This study compares spatial facilitation with line targets and collinear, edge-like inducers defined by luminance contrast to spatial facilitation with targets and inducers (...) defined by color contrast. The results of a first experiment show that achromatic inducers facilitate the detection of achromatic targets on gray and colored backgrounds, but tend to suppress the detection of chromatic targets. Chromatic inducers facilitate the detection of chromatic targets on gray and colored backgrounds, but tend to suppress the detection of achromatic targets. Chromatic spatial facilitation appears to be strongest when inducers and background are isoluminant. The results of a second experiment show that spatial facilitation with chromatic targets and inducers requires a longer exposure duration of the inducers than spatial facilitation with achromatic targets and inducers, which is already fully effective at an inducer exposure of 30 ms only. The findings point towards two separate mechanisms for spatial facilitation with collinear form stimuli: one that operates in the domain of luminance, and one that operates in the domain of color contrast. These results are consistent with neural models of boundary and surface formation which suggest that achromatic and chromatic visual cues are represented on different cortical surface representations that are capable of selectively attracting attention. Multiple copies of these achromatic and chromatic surface representations exist corresponding to different ranges of perceived depth from an observer, and each can attract attention to itself. Color and contrast differences between inducing and test stimuli, and transient responses to inducing stimuli, can cause attention to shift across these surface representations in ways that sometimes enhance and sometimes interfere with target detection. (shrink)

In this paper, I report new empirical data on folk semantic intuitions concerning color adjectives in so-called context-shifting experiments. Contextualists present such experiments — that is, they describe different conversational contexts in which a given sentence is uttered — in order to argue that context can shape meaning and truth conditions to such a degree that competent speakers would give opposite truth evaluations of the same sentence in different contexts. The initial findings of Hansen and Chemla (2013) suggest that (...) laypersons’ semantic judgments are sensitive to context in the same way that is predicted by contextualists. In this paper, I focus on context-shifting experiments that involve color adjectives; also, I present experiments that are a partial replication and methodological extension of Hansen and Chemla’s study. One aim of my study was to corroborate these authors’ findings using a bigger sample (total N = 1128), but the main goal was to test the stability of results in different methodological variants of empirical adaptations of context-shifting experiments. This part of the study addresses the issues pointed out in my earlier paper (Ziółkowski 2017), where I argued that certain experimental settings (within-subjects) might bring data that is more favorable to contextualism than other settings (between-subjects). My study compares three different experimental settings: within-subjects (with randomized order of context presentation), between-subjects (where participants evaluating different contexts aredistinct groups), and “contrastive design” (where both contexts are presented side by side on the same screen). My results are highly consistent across the methodological variants I employed, but while they show some of the effects expected by contextualists, it is disputable whether they bring strong support to contextualism with respect to color adjectives. (shrink)

Traditional theories locate color in primary qualities of objects, in dispositional properties of objects, in visual fields, or nowhere. In contrast, we argue that color is located in properties of light. More specifically, light is red iff there is a property P of the light that typically interacts with normal human perceivers to give the sensation of red. This is an error theory, because objects and visual fields that appear red are not really red, since they lack (...) the properties that make light red. We show how this light theory solves or avoids problems that afflict its competitors. (shrink)

We investigated how color preferences vary according to season and whether those changes could be explained by the ecological valence theory. To do so, we assessed the same participants’ preferences for the same colors during fall, winter, spring, and summer in the northeastern United States, where there are large seasonal changes in environmental colors. Seasonal differences were most pronounced between fall and the other three seasons. Participants liked fall-associated dark-warm colors—for example, dark-red, dark-orange, dark-yellow, and dark-chartreuse—more during fall than (...) other seasons. The EVT could explain these changes with a modified version of Palmer and Schloss’ weighted affective valence estimate procedure that added an activation term to the WAVE equation. The results indicate that color preferences change according to season, as color-associated objects become more/less activated in the observer. These seasonal changes in color preferences could not be characterized by overall shifts in weights along cone-contrast axes. (shrink)

Synaesthetes persistently perceive certain stimuli as systematically accompanied by illusory colours, even though they know those colours to be illusory. This appears to contrast with cases where a subject’s colour vision adapts to systematic distortions caused by wearing coloured goggles. Given that each case involves longstanding systematic distortion of colour perception that the subjects recognize as such, how can a theory of colour perception explain the fact that perceptual adaptation occurs in one case but not the other? I argue (...) that these cases and the relationship between them can be made sense of in light of an existing view of colour perception. Understanding colours as ways in which objects and surfaces modify light, perceived through grasping patterns and variations in colour appearances, provides a framework from which the cases and their apparent disanalogy can be predicted and explained. This theory’s ability to accommodate these cases constitutes further empirical evidence in its favour. (shrink)

Our modern scientific explanation of colour as a subjective impression has replaced a ‘pre-theoretical’ notion of colour as an intrinsic property of objects, which was mainstream in ancient thought. Why have we lost such pre-theoretical notion, and what have we lost by losing it? I argue that most ancient Greek philosophers exploited this pre-theoretical assumption – one that was obvious to them – in terms and ways that are still worthy of attention in the context of contemporary philosophy of colour. (...) I offer an in-depth analysis of the theories of a number of early Greek philosophers, as well as of Plato in the Timaeus, showing that they tend to share the idea that colour is an essential property of external bodies and therefore plays a causal role in perception. Then I focus on a comparison between Democritus’ stance and Aristotle’s in order to highlight a significant contrast between the two. Democritus' theory is an exception in ancient thought because it traces the colour phenomenon back to a refraction of atmospheric light through atomic aggregates. Aristotle, instead, posits the presence of colour and light in the bodies themselves. Finally, I interpret Aristotle's account as the most complex attempt in ancient thought to weld together what we call the ‘manifest image’ of colour and its ‘scientific image’. (shrink)

The article discusses the characterization of the visualization of visible reality in Crime and Punishment by Fyodor Dostoyevsky. The author suggests that semiotic and legal analysis should be used to understand the meaning of the color code of the novel. Semiotic discourse reduces the ambiguity, uncertainty, and expression of the color code to a conscious, discrete, and conditioned meaning of individual colors. Legal analysis helps to better understand the main idea and other aspects of the novel, encoded in (...) colors. Psychological, personal associations, and symbolic methods are used to reveal direct and indirect meaning of the colors used by Dostoyevsky. The basic characterization of colors proposed by Goethe is employed as a key for color decoding. The article also establishes the correlation of the color code of the novel with the colors of the flags of the Russian Empire and the German Confederation. The message and meaning of the same colors of these national flags are contrasted. The interpretation is complemented by the author’s drawings, which enable to visualize the color code that stores and transmits information about national identity. (shrink)

Matthen’s semantic theory of color is compared and contrasted with a variety of dispositionalism, to be called response-intentionalism (since it claims that color is a disposition to produce intentional states involving color-looks. First, it is argued that the two theories are not so far from each other; Matthen might be a closed dispositionalist, since he does stress the causal power of surfaces to produce color representations (signs). Next, the pragmatist component of his theory is addressed. Can (...) usefulness unify color? It seems that some degree of unity is required for a plurality of things to be treated as a group useful in a specifi c way: existence is prior to usefulness, not the other way around. Finally, the dispositionalism (including response-intentionalism) is defended against Mohan’s epistemological objection, according to which the dispositionalist cannot account for a priori nature of one’s knowledge of color looks; it is argued that it can,and that it can even use roughly the same means as semantic realism. (shrink)

Matthen’s semantic theory of color is compared and contrasted with a variety of dispositionalism, to be called response-intentionalism (since it claims that color is a disposition to produce intentional states involving color-looks. First, it is argued that the two theories are not so far from each other; Matthen might be a closed dispositionalist, since he does stress the causal power of surfaces to produce color representations (signs). Next, the pragmatist component of his theory is addressed. Can (...) usefulness unify color? It seems that some degree of unity is required for a plurality of things to be treated as a group useful in a specifi c way: existence is prior to usefulness, not the other way around. Finally, the dispositionalism (including response-intentionalism) is defended against Mohan’s epistemological objection, according to which the dispositionalist cannot account for a priori nature of one’s knowledge of color looks; it is argued that it can,and that it can even use roughly the same means as semantic realism. (shrink)

We have used fMRI to measure responses to chromatic and achromatic contrast in retinotopically defined regions of macaque and human visual cortex. We make four observations. Firstly, the relative amplitudes of responses to color and luminance stimuli in macaque area V1 are similar to those previously observed in human fMRI experiments. Secondly, the dorsal and ventral subdivisions of macaque area V4 respond in a similar way to opponent (L j M)-cone chromatic contrast suggesting that they are part (...) of a single functional area. Thirdly, we find that macaque area V4, like area V1, responds preferentially to chromatic contrast compared to luminance contrast and the degree of preference is strongly influenced by the temporal frequency of the stimulus. Finally, we observe that while macaque V4d is a region on the dorsal surface of the macaque visual cortex that responds robustly to chromatic stimuli, human chromatic responses to identical stimuli are largely confined to the ventral surface suggesting a fundamental difference in the topographical organization of higher visual areas between humans and macaques. (shrink)

This chapter focuses on the notion of color as a property of the surfaces of objects. It considers three positions on what colors are: objectivist, subjectivist, and relationalist. Examination of the arguments of the objectivists will help us understand how they seek to reduce color to a physical property of object surfaces. Subjectivists, by contrast, seek to argue that no such reduction is possible, and hence that color must be wholly subjective. This chapter argues that when (...) functional considerations are taken into account, a relationalist position best accommodates the primary data concerning color perception, and permits a better understanding of the ways in which color is both objective and subjective. The chapter ends with a reconsideration of the notions of objectivity and subjectivity themselves, and a consideration of how modern technology can foster misleading expectations about the specificity of color properties. (shrink)