Knowledge and Skepticism

8. Revelations: On What Is Manifest in Visual Experience

8 Revelations: On What Is Manifest in Visual Experience Joseph T. Tolliver The Doctrine of Revelation for Colors In ‘‘How to Speak of the Colors,’’ Mark Johnston articulates several theses he takes to be part of our commonsense conception of color. They include: Paradigms: Some of what we take to be paradigms of canary yellow things (e.g. some canaries) are canary yellow. Explanation: The fact of a surface or volume or radiant source being canary yellow sometimes causally explains our visual experience as of canary yellow things. Unity: Thanks to its nature and the nature of the other determinate shades, canary yellow, like the other shades, has its own unique place in the network of similarity, difference and exclusion relations exhibited by the whole family of shades. (Think of the relations exemplified along the axes of hue, saturation and brightness in the so-called color solid. The color solid captures central facts about the colors, e.g. that canary yellow is not as similar to the shades of blue as they are similar among themselves, i.e. that canary yellow is not a shade of blue.) Perceptual availability: Justified belief about the canary yellowness of external things is available simply on the basis of visual perception. That is, if external things are canary yellow we are justified in believing this just on the basis of visual perception and the beliefs which typically inform it. (Further philosophical explication of this belief would come to something like this: if you are looking at a material object under what you take to be adequate conditions for perceiving its color and you take yourself to be an adequate perceiver of color then your visually acquired belief that the material object is canary yellow is justified simply on the strength of (i) the information available in the relevant visual experience and (ii) those general background beliefs about the external causes of visual experience which inform ordinary perception.)1 My concern is with the last doctrine, namely, Revelation: Revelation: The intrinsic nature of canary yellow is fully revealed by a standard visual experience as of a canary yellow thing. For a yellow canary, see figure 8.1 (plate 1). As an example of an endorsement of Revelation, Johnston quotes Russell ’s discussion of the knowledge of colors by acquaintance, in his The Problems of Philosophy. The particular shade of colour that I am seeing may have many things said about it— I may say that it is brown, that it is rather dark, and so on. But such statements, though they make me know truths about the colour, do not make me know the colour itself any better than I did before: so far as concerns knowledge of the colour itself, as opposed to knowledge of truths about it, I know the colour perfectly and completely when I see it, and no further knowledge of it itself is even theoretically possible.2 Figure 8.1 Goldfinch mule near clear canary. See plate 1. 182 J. T. Tolliver And this from Galen Strawson: ‘‘color words are words for properties which are of such a kind that their whole and essential nature as properties can be and is fully revealed in sensory-quality experience given only the qualitative character that that experience has.’’3 Both of these statements of Revelation focus on color properties, but are clearly intended to capture a feature of a whole class of properties. A more general characterization of this idea might look like the following: (Rev.) There are perceivable qualities Q such that, a normal experience as of Q has a qualitative character C, such that, a subject’s awareness of C is sufficient for the subject to fully know the intrinsic nature of a way a thing is when it is Q. (Rev.) captures the idea that there are qualities in the world that have their intrinsic natures, what they are in themselves, fully revealed by the means of the qualitative character of normal experiences of them. The force of the ‘‘fully’’ is given by the comparison to what science can tell us about the colors: n The relationship between color and the underlying physical and chemical make-up of colored things; n The psychophysics of the perception of color; n The neurophysiology of the encoding and exploitation of color information in the brain; n The semantics of color categorization and color naming systems. Science delivers a variety of...