Modern color science finds its birth in the middle of the nineteenth century. Among the chief architects of the new color theory, the name of the polymath Hermann von Helmholtz stands out. A keen experimenter and profound expert of the latest developments of the fields of physiological optics, psychophysics, and geometry, he exploited his transdisciplinary knowledge to define the first non-Euclidean line element in color space, i.e., a three-dimensional mathematical model used to describe color differences in (...) terms of color distances. Considered as the first step toward a metrically significant model of color space, his work inaugurated researches on higher color metrics, which describes how distance in the color space translates into perceptual difference. This paper focuses on the development of Helmholtz’s mathematical derivation of the line element. Starting from the first experimental evidence which opened the door to his reflections about the geometry of color space, it will be highlighted the pivotal role played by the studies conducted by his assistants in Berlin, which provided precious material for the elaboration of the final model proposed by Helmholtz in three papers published between 1891 and 1892. Although fallen into oblivion for about three decades, Helmholtz’s masterful work was rediscovered by Schrödinger and, since the 1920s, it has provided the basis for all subsequent studies on the geometry of color spaces up to the present time. (shrink)

Amblyopia, or lazy eye, is a neurological vision disorder that studies have shown to affect two to five percent of the population. Current methods of treatment produce the best visual outcome, if the condition is identified early in the patient's life. Several early screening procedures are aimed at finding the condition while the patient is a child, including an automated vision screening system. This paper aims to use artificial intelligence techniques to automatically identify children who are at risk for developing (...) the amblyopic condition and should therefore be referred to a specialist, i.e., pediatric ophthalmologist. Three techniques, namely, decision tree learning, random forest, and artificial neural network, are studied in this paper in terms of their effectiveness, using metrics of sensitivity, specificity, and accuracy. The features used by the techniques are extracted from images of patient eyes and are based on the color information. The efficacy of pixel color data is investigated with respect to the measurement of the rate of change of the color in the iris and pupil, i.e., color slope features. A 10-fold stratified cross validation procedure is used to compare the effectiveness of the three AI techniques in this medical application domain. (shrink)

Systems for color naming across languages have been a fascinating topic for decades. Zaslavsky and colleagues challenge Gibson's argument that color names are shaped by patterns of communicative need. Using an information‐theoretic analysis, they show that color naming is shaped by both perceptual structure (as is usually argued) but also by communication need.

There is growing body of knowledge about how humans and animals perceive col- ours; we may safely say that both physiology and physics of colour perception are becoming less and less mysterious. Still it doesn't help to solve a philosophical puzzle: What do exactly mean expressions like “perceived red” or “perceived green”? What do perceived colours refer to in the world? There are three problem fields I am touching on in this paper: (i) semantics of colour names, (ii) ontological status (...) of colours, (iii) cognitive relevance of colours. I am trying to formulate onto- logical and epistemological assumptions for semantics of colour names. I am espe- cially focused on classical problem of objectivity of colours. While pursuing my task I am making some critical remarks about Wittgenstein's views on colours as formulated in “Tractatus” and modified in “Remarks on Colours”. I am using. (shrink)

The simulations of Steels & Belpaeme (S&B) suggest that communication could lead to color categories that are closely shared within a language and potentially diverge across languages. We argue that this is opposite of the patterns that are actually observed in empirical studies of color naming. Focal color choices more often exhibit strong concordance across languages while also showing pronounced variability within any language.

In their article ‘In defense of incompatibility, objectivism, and veridicality about color’ P. Roberts and K. Schmidtke offer the results of an experiment supposed to show that if selection of colored samples representing unique hues for subjects has a greater inter-subject variability than identification of sample pairs with no perceptual difference between them the result provides support for the philosophical concept of color realism. On examining the results in detail, we find that, according to standard statistical methodology, the (...) relative magnitude of inter-subject variability in the matching experiment is for both tested colors larger than that in the naming experiment, thus invalidating their claims. In addition, we point out several serious shortcomings in the experiment. (shrink)

We recently conducted an experiment to show that a lot of the empirically measured disagreement cited to support the premise that there is mass perceptual disagreement about the colors, a premise often cited by philosophers, is due to conceptual factors. Kuehni and Hardin object to how we measured disagreement and to various aspects of our experimental design. In this reply, we defend our study.

Much research on color representation and categorization has assumed that relations among color terms can be proxies for relations among color percepts. We test this assumption by comparing the mapping of color words with color appearances among different observer groups performing cognitive tasks: an invariance of naming task; and triad similarity judgments of color term and color appearance stimuli within and across color categories. Observer subgroups were defined by perceptual phenotype and (...) photopigment opsin genotype analyses. Results suggest that individuals rely on at least two different representational models of color experience: one lexical, conforming to the culture's normative linguistic representation, and another individual perceptual representation organizing each observer's color sensation experiences. Additional observer subgroup analyses suggest that perceptual phenotype variation within a language group may play a greater role in the shared color naming system than previously thought. A reexamination of color naming data in view of these findings may reveal influences on color naming important to current theories. (shrink)

In Basic Color Terms, Berlin and Kay argued for a restricted number of "basic" color words—words they claimed to be culturally universal. This claim about language was buttressed by psychologist Eleanor Rosch's famous work on color prototypes. Together, the works of Berlin and Kay and Rosch are the foundation for a contemporary research tradition investigating the biological foundations of color naming. In this article, the author describes some common objections to the works of Berlin and (...) Kay and Rosch and argues that they are not significant. The claim that explanations of color naming ought to be strictly cultural also is discussed and rejected. (shrink)

In "Does the Basic Color Terms discussion suffer from the Stimulus Error?" Rolf Kuehni describes a research stumbling block known as the "stimulus error," and hints at the difficulties it causes for mainstream color naming research. Among the issues intrinsic to Kuehni's "stimulus error" description is the important question of what can generally be inferred from color naming behaviors based on bounded samples of empirical stimuli. Here we examine some specifics of the color (...) class='Hi'>naming research issues that Kuehni raises. While we share Kuehni's view regarding potential problems caused by the "stimulus error" and his concern regarding its prevalence, Kuehni's commentary seems primarily aimed at stimulating a general discussion of color naming research implications, because the articles he critiques do not actually commit the "stimulus error" in any serious sense. Based on Kuehni's comments, we further examine some of the relevant empirical and theoretical implications for cross-cultural color naming research. (shrink)

Saunders & van Brakel's claim that Berlin and Kay (1969) assumed a language/vision correlation in the area of color categorization and disguised this assumption as a finding is shown to be false. The methodology of the World Color Survey, now nearing completion, is discussed and the possibility of an additional language/vision correlation in color categorization is suggested.

Confusion concerning the issue of universality of colour categorization would greatly diminish if context regains its fundamental status in psychological research and we give up on the reductionist notion that biological universality implies behavioral universality.

The paper presents an approach to encrypt the color images using bit-level permutation and alternate logistic map. The proposed method initially segregates the color image into red, green, and blue channels, transposes the segregated channels from the pixel-plane to bit-plane, and scrambles the bit-plane matrix using Arnold cat map (ACM). Finally, the red, blue, and green channels of the scrambled image are confused and diffused by applying alternate logistic map that uses a four-dimensional Lorenz system to generate a (...) pseudorandom number sequence for the three channels. The parameters of ACM are generated with the help of Logistic-Sine map and Logistic-Tent map. The intensity values of scrambled pixels are altered by Tent-Sine map. One-dimensional and two-dimensional logistic maps are used for alternate logistic map implementation. The performance and security parameters histogram, correlation distribution, correlation coefficient, entropy, number of pixel change rate, and unified averaged changed intensity are computed to show the potential of the proposed encryption technique. (shrink)

What makes it the case that we draw the boundary between “blue” and “green” where we draw it? Do we draw this boundary where we draw it because our perceptual system is biologically determined in this way? Or is it culture and language that guide the way we categorize colors? These two possible answers have shaped the historical discussion opposing so-called universalists to relativists. Yet, the most recent theoretical developments on color categorization reveal the limits of such a polarization.

Subfocal Color Categorization and Naming: The Role of Exposure to Language and Professional Experience The current state of the debate on the linguistic factors in color perception and categorization is reviewed. Developmental and learning studies were hitherto almost ignored in this debate. A simple experiment is reported in which 20 Academy of Fine Arts, Faculty of Painting students' performance in color discrimination and naming tasks was compared to the performance of 20 Technical University students. Subfocal (...) colors were used. While there was no difference in overall discrimination ability, AFA students had a much richer and specialized color vocabulary. Both groups also applied different strategies of discrimination and naming. However, naming system in neither group was coherent. This suggests that naming played primarily the role of markers for control processes rather than names for categories. It is concluded that up-to-date debate is too simplified and a complex model of interrelations between perceptual categorization and naming framed in the developmental context is needed rather than the search for a simple answer "language", "environment", or "perceptual universals". (shrink)

If the so-called 'science wars' are futile shouting-matches between extremists, some of the more bewildering skirmishes have been contested in the realm of colour science and culture. Ethnographers, postmodernists, and Wittgensteinians stress the specificity of local colour naming strategies, or the peculiarity of objects and emotions with which colours are associated, and may confess lingering attraction to Whorf's idea that cultures carve up an intrinsically unstructured colour space into quite arbitrary linguistic categories. Self-proclaimedly hard-headed biological and evolutionary psychologists, in (...) contrast, argue that the pan-human physiology of colour perception determines our colour categorization, and constrains whatever minimal linguistic variability there is. Don Dedrick's wonderful study in the philosophy of cognitive science offers not only a careful survey of the relevant evidence in this stand-off, but also a persuasive set of tools for thinking the issues through quite differently, and for avoiding the dichotomous terms in which the debates have previously been couched. The book should be essential reading for colour scientists, and for philosophers interested in links between cognition and culture; and it offers useful advanced introductions to detailed technical literatures in psychophysics, colour linguistics, and cognitive anthropol. (shrink)

This chapter explores the evidence for the existence of such new colour experiences and what their philosophical ramifications would be. I first define the notion of ‘novel colours’ and discuss why I think that this is the best name for such colours, rather than the numerous other names that they have sometimes been given in the literature. I then introduce the evidence and arguments for thinking that experiences as of novel colours exist, along with objections that people have had to (...) that evidence and to those arguments. To do so, I outline some facts about ordinary, non-novel colours before considering whether experiences as of novel colours, exist. Then I discuss the potentially significant ramifications the existence of novel colour experiences would have for theories of the metaphysics of colour, theories of the nature of colour experience, and for theories of the nature of perception more generally. (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)

Cross-cultural studies of color naming show that basic terms are universally the most frequently used to name colors. However, such basic color terms are always used in the context of larger linguistic systems when specific properties of color experience are described. To investigate naturalistic naming behaviors, we examined the use of modifiers in English and Vietnamese color naming using an unconstrained naming task. Monolingual and bilingual subjects named a representative set of 110 (...) color stimuli sampled from a commonly used color-order stimulus space. Results revealed greater reliance upon polylexemic naming among monolingual Vietnamese speakers and greater use of monolexemic basic hue terms and secondary terms among monolingual English speakers. Systematic differences across these language groups imply that widely used monolexemic naming methods may differentially impact color-naming findings in cross-cultural investigations of color cognition. (shrink)

By spotlighting the irreducible role of cognitive processes between biology and culture, this synthesis and critique of the universalist tradition in colour science offers a genuine starting-point for all future 'serious inquiry into the relationship between linguistic and non-linguistic aspects of colour classification'.

Many philosophers, especially in the wake of the 17th century, have favored an inegalitarian view of shape and color, according to which shape is mind-independent while color is mind-dependent. In this essay, I advance a novel argument against inegalitarianism. The argument begins with an intuition about the modal dependence of color on shape, namely: it is impossible for something to have a color without having a shape. I then argue that, given reasonable assumptions, inegalitarianism contradicts this (...) modal-dependence principle. Given the plausibility of the latter, I conclude that we should reject inegalitarianism in favor of some form of egalitarianism—either a subjective egalitarianism on which both shape and color are mind-dependent or an objective egalitarianism on which both shape and color are mind-independent. (shrink)

Since the publication of Brent Berlin and Paul Kay's Basic color terms in 1969 there has been continuing debate as to whether or not there are linguistic universals in the restricted domain of color naming. In this paper I am primarily concerned with the attempt to explain the existence of basic color terms in languages. That project utilizes psychological and ultimately physiological generalizations in the explanation of linguistic regularities. The main problem with this strategy is that (...) it cannot account for a particular subset of basic color words: words that the Berlin-Kay tradition calls “composite”. The existence of such words does not compromise the claim that there are basic color words. It does suggest that such words—and basic terms in general—require a more complex type of explanatory strategy than much contemporary work on color naming supposes. It is my main contention that the central problems with the Berlin-Kay tradition arise from the difficulty of linking conceptually and empirically disparate domains: linguistic, psychological, physiological. What is needed is not an attempt to reduce color naming to biology or to culture but, rather, an adequate conceptual account of how people may come to have and use basic color terms—an account which stands between the biological and the cultural. (shrink)

In America today, the problem of achieving racial justice--whether through "color-blind" policies or through affirmative action--provokes more noisy name-calling than fruitful deliberation. In Color Conscious, K. Anthony Appiah and Amy Gutmann, two eminent moral and political philosophers, seek to clear the ground for a discussion of the place of race in politics and in our moral lives. Provocative and insightful, their essays tackle different aspects of the question of racial justice; together they provide a compelling response to our (...) nation's most vexing problem.Appiah begins by establishing the problematic nature of the idea of race. He draws on the scholarly consensus that "race" has no legitimate biological basis, exploring the history of its invention as a social category and showing how the concept has been used to explain differences among groups of people by mistakenly attributing various "essences" to them. Appiah argues that, while people of color may still need to gather together, in the face of racism, under the banner of race, they need also to balance carefully the calls of race against the many other dimensions of individual identity; and he suggests, finally, what this might mean for our political life.Gutmann examines alternative political responses to racial injustice. She argues that American politics cannot be fair to all citizens by being color blind because American society is not color blind. Fairness, not color blindness, is a fundamental principle of justice. Whether policies should be color-conscious, class conscious, or both in particular situations, depends on an open-minded assessment of their fairness. Exploring timely issues of university admissions, corporate hiring, and political representation, Gutmann develops a moral perspective that supports a commitment to constitutional democracy.Appiah and Gutmann write candidly and carefully, presenting many-faceted interpretations of a host of controversial issues. Rather than supplying simple answers to complex questions, they offer to citizens of every color principled starting points for the ongoing national discussions about race. (shrink)

Could there be genuinely novel colours — that is, visual qualities having a hue that bears a resemblance relation to red, green, yellow, and blue, yet is neither reddish, nor greenish, nor yellowish, nor blueish?1 And if there could be such colours, what would it be like to see them? How would the colours look? In his article,"Epiphenomenal Qualia,"2 Frank Jackson presents a philosophical thought experiment that raises these questions . Jackson asks us to imagine a perceiver named Fred who (...) is like us except that he has the ability to see a hue we cannot see. Jackson's question is: "What is the new colour or colours like?"3 Jackson argues that all the physical information about Fred, including the physiology of his brain and visual system, and his dispositions to behaviour, would not enable us to answer this question. The totality of physical information would still leave out something about Fred's experience, namely, what the extra hue is like from the subjective perspective of Fred. And if at some point we became able to see this extra hue , we would learn something that we did not know as a result of having all the physical information about Fred: We would learn how the extra hue looks and thereby learn just what it was that made Fred's experience different from ours. Jackson calls his argument "the knowledge argument." In his view, the argument is similar to Thomas Nagel's in his article "What is it Like to Be a Bat?,"4 but both its point and ultimate conclusion are different. Nagel argues that facts about what conscious experience is like for some creature are essentially connected to the subjective perspective of the creature. The problem that Nagel poses is, how could such facts be revealed in anything objective and physical about the creature? How could the objective characterization indicate what it is like to be the creature ? The point of Jackson's argument, however, is not that we would not know what it is like to be Fred even if we knew everything physical about him ; it is rather that there is still something we do not know about Fred's experience — a property that it has — even when we have all the physical information about him: We do not know how the extra hue that Fred sees looks to Fred, and so we do not know all that there is to know about how Fred's experience of seeing the extra hue differs from his experience of seeing red, green, yellow, and blue.5 Jackson's conclusion is also stronger than Nagel's. (shrink)

It is argued that colour name strategy, object name strategy, and chunking strategy in memory are all aspects of the same general phenomena, called stereotyping, and this in turn is an example of a know-how representation. Such representations are argued to have their origin in a principle called the minimum duplication of resources. For most the subsequent discussions existence of colour name strategy suffices. It is pointed out that the BerlinA- KayA universal partial ordering of colours and the frequency of (...) traffic accidents classified by colour are surprisingly similar; a detailed analysis is not carried out as the specific colours recorded are not identical. Some consequences of the existence of a name strategy for the philosophy of language and mathematics are discussed: specifically it is argued that in accounts of truth and meaning it is necessary throughout to use real numbers as opposed to bi-valent quantities; and also that the concomitant label associated with sentences should not be of unconditional truth, but rather several real-valued quantities associated with visual communication. The implication of real-valued truth quantities is that the Continuum Hypothesis of pure mathematics is side-stepped, because real valued quantities occur ab initio. The existence of name strategy shows that thought/sememes and talk/phonemes can be separate, and this vindicates the assumption of thought occurring before talk used in psycho-linguistic speech production models. (shrink)