(Tye 2006) presents us with the following scenario: John and Jane are both stan- dard human visual perceivers (according to the Ishihara test or the Farnsworth test, for example) viewing the same surface of Munsell chip 527 in standard conditions of visual observation. The surface of the chip looks “true blue” to John (i.e., it looks blue not tinged with any other colour to John), and blue tinged with green to Jane.¹ Tye then in effect poses a multiple choice question.

What ecological advantages do animals gain by being able to detect, extract and exploit wavelength information? What are the advantages of representing that information as hue qualities? The benefits of adding chromatic to achromatic vision, marginal in object detection, become apparent in object recognition and receiving biological signals. It is argued that this improved performance is a direct consequence of the fact that many animals' visual systems reduce wavelength information to combinations of four basic hues. This engenders a simple categorical (...) scheme that permits a rich amount of sensory information to be rapidly and efficiently employed by cognitive machinery of limited capacity. (shrink)

It can happen that a single surface S, viewed in normal conditions, looks pure blue (“true blue”) to observer John but looks blue tinged with green to a second observer, Jane, even though both are normal in the sense that they pass the standard psychophysical tests for color vision. Tye (2006a) finds this situation prima facie puzzling, and then offers two different “solutions” to the puzzle.1 The first is that at least one observer misrepresents S’s color because, though normal in (...) the sense explained, she is not a Normal color observer: her color detection system is not operating in the current condition in the way that Mother Nature intended it to operate. His second solution involves the idea that Mother Nature designed our color detection systems to be reliable with respect to the detection of coarse-grained colors (e.g., blue, green, yellow, orange), but our capacity to represent the fine-grained colors (e.g., true blue, blue tinged with green) is an undesigned spandrel. On this second solution, it is consistent with the variation between John and Jane that both represent the color of S in a way that complies with Mother Nature’s intentions: both represent S as exemplifying the coarse-grained color blue, and since (we may assume) S is in fact blue, both represent it veridically. Of course, they also represent fine-grained colors of S, and, according to Tye, at most one of these representations is veridical (Tye says that only God knows which). But at the level of representation for which Mother Nature designed our color detection systems, both John and Jane (qua Normal observers) are reliable detectors. (shrink)

Color -order systems highlight certain features of color phenomenology while neglecting others. It is misleading to speak as if there were a single “psychological color space” that might be described by a rather simple formal structure. Criticisms of functionalism based on multiple realizations of a too-simple formal description of chromatic pheno-menal relations thus miss the mark. It is quite implausible that a functional system representing the full complexity of human color phenomenology should be realizable by radically different qualitative states.

Paul Churchland proposed a conceptual framework for translating reflectance profiles into a space he takes to be the color qualia space. It allows him to determine color metamers of spectral surface reflectances without reference to the characteristics of visual systems, claiming that the reflectance classes that it specifies correspond to visually determined metamers. We advance several objections to his method, show that a significant number of reflectance profiles are not placed into the space in agreement with the qualia solid, and (...) produce two sets of counterexamples to his claim for metamers. (shrink)

Because our only access to color qualities is through their appearance, Byrne & Hilbert's insistence on a strict distinction between apparent colors and real colors leaves them without a principled way of determining when, if ever, we see colors as they really are.

This paper is an introduction to a teaching series entitled, “Teaching Philosophers to Teach.” The series addresses graduate student teaching methods. The introduction outlines pedagogical goals and practices of the graduate curriculum of the Syracuse Program. The Program addresses the unequal distribution between high intellectual performance and good teaching amongst graduate students. Instead of focusing on graduate student values and beliefs on teaching, the Program curriculum addresses the particular institutional practices that shape student teaching. Some of the suggested changes, which (...) aim to reaffirm the link between philosophical thinking and teaching, include changing the duration of teaching training, assigning a faculty teaching mentorship to students at the beginning of their graduate studies, and emphasizing best practices in teaching assistantships. The papers in this series address teaching-related issues ranging from classroom pedagogy to graduate student training. (shrink)

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)

If, as Saunders & van Brakel assert, hue, lightness, and saturation characterize artificial color spaces and not the colors of everyday life, one would expect those color spaces to have limited relevance to our understanding of color phenomena and to be of little practical application. This is not the case. Although people perceive these and equivalent color dimensions holistically rather than analytically, they are able to use such triples to categorize the colors of their environment.

Painters are the experts in colour phenomenology. Their business is to use colour to affect our feelings. Psychophysicists are expert in making experimental inferences from behavioural responses to the functional mechanisms of perception. The varying aims of these two groups of people mean that much that is of interest to the one is of little concern to the other. However, in recent times several prominent psychophysicists, such as Floyd Ratliff , Jack Werner and Dorothea Jameson , have thrown much light (...) on painterly practice. Following their lead, I would like to sketch some of the mechanisms that are responsible for many of the features of colour appearance important to the work of visual artists. I will begin with some phenomena that can be accounted for by mechanisms that are reasonably well understood, and then move to phenomena whose underlying basis is less well established. I will conclude with a suggestive experiment and, true to my calling as a philosopher, a piece of downright speculation. (shrink)

Can qualia be analyzed by theories that contain only non-qualitative terms? A host of philosophers including Block, Levine, Nagel, and Jackson have argued that, in principle, they cannot. And yet psychophysicists have advanced explanations that seem to account for sensory appearances in terms of the operations of nervous systems. Here are some examples: Mach bands, the assimilation effect, and the Hermann grid illusion all have to do with the look of things, and all are routinely thought to be a consequence (...) of the structure of visual receptive fields. Simultaneous contrast and auditory tuning—both perceptual effects—are lateral inhibition phenomena. That television sets with only three phosphor colors can replicate natural scenes with thousands of distinguishable colors is due to our eyes having just three photopigments. The difference between a three-type receptoral configuration and an array of thousands of receptors with distinct responses accounts for the fact that hues form a closed loop in color space, whereas there are no closed pitch loops in auditory space. (shrink)