David R. Hilbert

Larry Hardin has been the most steadfast and influential critic of physicalist theories of color over the last 20 years. In their modern form these theories originated with the work of Smart and Armstrong in the 1960s and 1970s1 and Hardin appropriately concentrated on their views in his initial critique of physicalism.2 In his most recent contribution to this project3 he attacks Michael Tye’s recent attempts to defend and extend color physicalism.4 Like Byrne and Hilbert5, Tye identifies color with the reflecting properties of objects (“reflectance physicalism”). Specifically, the determinate and determinable colors are identified with types of reflectances. (Setting some complications aside, the reflectance of an object is the proportion of light that it reflects at each wavelength in the visible spectrum.) These reflectance types are, in the terminology of Hilbert, anthropocentric—in the terminology of Lewis6, they are not very “natural”.

The Dangerous Book for Boys Abstract: Seventeenth and eighteenth century discussions of the senses are often thought to contain a profound truth: some perceptible properties are secondary qualities, dispositions to produce certain sorts of experiences in perceivers. In particular, colors are secondary qualities: for example, an object is green iff it is disposed to look green to standard perceivers in standard conditions. After rebutting Boghossian and Velleman’s argument that a certain kind of secondary quality theory is viciously circular, we discuss three main lines of argument for the secondary quality theory. The first is inspired by an intuitively compelling picture of perception articulated by Reid; the second is that the secondary quality theory is a conceptual truth; the third line of argument is presented in Johnston’s influential paper ‘How to speak of the colors’. We conclude that all these arguments fail, and that the secondary quality theory is unmotivated. Keywords: color, secondary quality, disposition, vision, perception..

Naturalistic theories of content and whether or not reason-giving explanations of human behavior are causal explanations have been central topics in recent philosophy of mind. Fred Dretske, in his book Explaining Behavior, attempts to construct a naturalistic theory of the contents of beliefs and desires that gives these mental states an important role in the causation of behavior. Even if Dretske is granted that the theory adequately accounts for individual behaviors the theory still faces problems in offering an adequate account of important features of extended sequences of behavior. Some sequences of behavior exhibit coherence in the sense that the elements of the sequence either contribute to the atttainment of a goal state or only make sense on the supposition that the goal state will be attained. Two ways of attaining coherence are distinguished. In chaining behavior coherence is guaranteed by the fit between the internal structure of the organism and the structure of the external environment. In other cases of coherence chaining is not available as an explanation. It is argued that Dretske.

Deeply original, inspiring to some, abhorrent to others, George Berkeley’s philosophy of immaterialism is still influential three hundred years after the publication of his most widely read book, _Three Dialogues Between Hylas and Philonous. _Berkeley published the _Dialogues _because of the unenthusiastic reception of his _Principles of Human Knowledge _in 1710._ _He hoped the use of the_ _dialogue format would win a more favorable hearing, but unfortunately for Berkeley, the response was every bit as scathing as the reception of his previous work. In recent decades, Berkeley’s work has been recognized as an excellent introduction to the English philosophy of the eighteenth century, and to philosophy in general. This edition of the dialogues is accessibly organized by David Hilbert and John Perry.

The target article is an attempt to make some progress on the problem of color realism. Are objects colored? And what is the nature of the color properties? We defend the view that physical objects (for instance, tomatoes, radishes, and rubies) are colored, and that colors are physical properties, specifically types of reflectance. This is probably a minority opinion, at least among color scientists. Textbooks frequently claim that physical objects are not colored, and that the colors are "subjective" or "in the mind." The article has two other purposes: first, to introduce an interdisciplinary audience to some distinctively philosophical tools that are useful in tackling the problem of color realism and, second, to clarify the various positions and central arguments in the debate.

There are serious reasons for accepting each of these propositions individually but there are apparently insurmountable difficulties with accepting all three of them simultaneously if we assume that color is a single property. 1) and 2) together seem to imply that there is some property which all organisms with color vision can see and 3) seems to imply that there can be no such property. If these implications really are valid then one or more of these propositions will have to be rejected in spite of whatever reasons can be given for their apparent acceptability. Before going on to discuss possible resolutions of this apparent contradiction it is worth pointing out there our three propositions are not all of a kind. Proposition 1) is a metaphysical thesis about the ontological status of color and proposition 3) is an empirical thesis about what properties organisms with color vision are capable of detecting. If you accept 1) then 2) will appear to verge on the trivial, but if 1) is denied then the status of 2) will appear more problematic. In what follows I will have more to say about why we either should or should not accept all three of these propositions.

Anomaloscope An instrument used for detecting anomalies of color vision. The test subject adjusts the ratio of two monochromatic lights to form a match with a third monochromatic light. The most common form of this procedure involves a Rayleigh match: a match between a mixture of monochromatic green and red lights, and a monochromatic yellow light. Normal subjects will choose a matching ratio of red to green light that falls within a fairly narrow range of values. Subjects with anomalous color vision will choose a ratio of red to green that falls outside this range, and red-green dichromats will accept any ratio of red to green as forming a match

One of the traditional problems of philosophy is the nature of the connection between perceptual experience and empirical knowledge. That there is an intimate connection between the two is rarely doubted. Three case studies of visual deficits due to brain damage are used to motivate the claim that perceptual experience is neither necessary nor sufficient for perceptual knowledge. Acceptance of this claim leaves a mystery as to the epistemic role, if any, of perceptual experience. It is argued that one function of perceptual experience is to provide information about the sources of beliefs, both as to which perceptual modality and within a given modality. This information is useful in assessing the reliability of perceptual beliefs.

In Colour for Architecture, published in 1976, the editors, Tom Porter and Byron Mikellides, explain that their book was “produced out of an awareness that colour, as a basic and vital force, is lacking from the built environment and that our knowledge of it is isolated and limited.”1 Lack of urban color was then especially salient in Britain—where the book was published—which had just begun to recoil at the Brutalist legacy of angular stained gray concrete strewn across the postwar landscape. Perhaps because the most urgent need was to inject some hue into this architectural dystopia, one of the main innovations illustrated in the book involves nothing more than cans of paint. Dull unfinished concrete façades, the interior of a subway station, a cement works, and so on, are shown enlivened by fields of bright color.

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.

1. The “puzzle” Physical objects are coloured: roses are red, violets are blue, and so forth. In particular, physical objects have fine-grained shades of colour: a certain chip, we can suppose, is true blue (unique, or pure blue). The following sort of scenario is commonplace. The chip looks true blue to John; in the same (ordinary) viewing conditions it looks (slightly) greenish-blue to Jane. Both John and Jane are “normal” perceivers. Now, nothing can be both true blue and greenish-blue; since the chip is true blue, it is not greenish-blue. Hence Jane, unlike John, is misperceiving the chip. Generalizing, the conclusion is that there is widespread misperception of fine-grained shades. According to Tye (2006), and Cohen, Hardin, and McLaughlin (2006), the previous paragraph amounts to a paradox: an apparently unacceptable conclusion has been drawn from apparently acceptable premises via apparently acceptable reasoning. (See also Hawthorne and Kovakovich 2006, 180-1.) Tye swallows the conclusion, aided by a dose of evolutionary speculation. Hardin (1988), on the other hand, rejects the first premise, and denies that physical objects are coloured. Cohen (2004) and McLaughlin (2003) claim that both Jane and John have the colour of the chip right. Our opening paragraph concealed a crucial parameter. In fact, the chip looks greenish-blue-relative-to- circumstances-C to Jane, and true-blue-relative-to-circumstances-C* to John, and the chip has both these relativized colours.1 All this ingenious philosophizing would be in vain, of course, if the conclusion of the opening paragraph were not puzzling or problematic. So, why is it supposed to be? According to Tye, the conclusion is puzzling because John and Jane are both “normal perceivers” (xx). He seems to think that it is (prima facie) plausible to assume..

Philosophers have devoted a great deal of discussion to the question of whether an inverted spectrum thought experiment refutes functionalism. (For a review of the inverted spectrum and its many philosophical applications, see Byrne, 2004.) If Ho?man is correct the matter can be swiftly and conclusively settled, without appeal to any empirical data about color vision (or anything else). Assuming only that color experiences and functional relations can be mathematically represented, a simple mathematical result.

Perception and thought are often, although not exclusively, concerned with information about the world. In the case of perceiving though, unlike thinking, it is widely believed that there is an additional element involved, a subjective feeling or, as it is often put, something that it is like to be perceiving. Qualia are these characteristic feelings that accompany perceiving. One motivation for the idea that we experience qualia is that there is a clear difference between seeing a red tomato and thinking that a tomato is red and that the difference has to do with some extra element present in the case of seeing that is absent in the case of thinking. Philosophical attempts to understand qualia and their place in the world have played a central role in recent debates about the nature of mind and its place in the world. Before getting to those debates, we will take a more detailed look at the distinction between the content of perceptual experiences,what they tell us about the world, and their qualitative or phenomenal character, what it is like to experience them.

A sensible quality is a perceptible property, a property that physical objects (or events) perceptually appear to have. Thus smells, tastes, colors and shapes are sensible qualities. An egg, for example, may smell rotten, taste sour, and look cream and round.1,2 The sensible qualities are not a miscellanous jumble—they form complex structures. Crimson, magenta, and chartreuse are not merely three different shades of color: the first two are more similar than either is to the third. Familiar color spaces or color solids capture, to a greater or lesser extent, these relations between the colors. The same goes for sensible qualities perceived in other modalities: middle C, high C, and D are not merely three different notes, and the taste of lemons, oranges, and sugar cubes are not merely three different tastes. How can this structure of appearance be explained? One idea is that sensible qualities are of two sorts: basic and derived. The basic sensible qualities are the building blocks from which the derived sensible qualities can be..

The typical kind of color realism is reductive: the color properties are identified with properties specified in other terms (as ways of altering light, for instance). If no reductive analysis is available — if the colors are primitive sui generis properties — this is often taken to be a convincing argument for eliminativism. That is, realist primitivism is usually thought to be untenable. The realist preference for reductive theories of color over the last few decades is particularly striking in light of the generally anti-reductionist mood of recent philosophy of mind. The parallels between the mind—body problem and the case of color are substantial enough that the difference in trajectory is surprising. While dualism and non-reductive physicalism are staples, realist primitivism is by and large a recent addition to the color literature. And it remains a minority position, although one that is perhaps gaining support. In this paper, we investigate whether it should be accepted, and conclude it should not be