Monday, August 11, 2014

A Response to my Color Anti-realist Friend
In 1976, when I delivered the John Locke Lectures at Oxford, I often spent time with Peter Strawson, and one day at lunch he made a remark I have never been able to forget. He said, "Surely half the pleasure of life is sardonic comment on the passing show".  This blog is devoted to comments, not all of them sardonic, on the passing philosophical show.
Hilary Putnam

My old friend JW writes:

“I am not clear if you are claiming the ‘greenness’ that I can successfully ascribe through repeated experience of my lawn as colour constancy to be itself a physical property of the object in a particular state (which position teasingly I refer to as ‘farbe an sich’), because elsewhere you recently said that there is no such thing as ‘being' green.  

“Or, are you saying that other physical properties of the object cause me (and most others with my kind of eyes) to see light of such and such a frequency in such and such a scatter under such and such an illumination as the same green (more or less) as my lawn was yesterday - given that it has rained on both days - which is good for the garden in this heat - even if the look of it is different from morning to evening, from day to day.  This would mean that green objects have the same or similar physical properties but not necessarily that these properties are in and of themselves green, just green inducing to my kind of eyes?”

I want to share my responses to my friend’s questions, so that he and the other readers of this blog will be clear on what I am saying and what I am not saying. One thing I did not say was that there is no such thing as being green.

Escher colors again
What I wrote, in my post of June 11 (“Escher Colors”) - after pointing out that even for normal viewers there is a slight (but noticeable if one attends to it) difference between the shade of color an object appears when viewed with the left eye closed and when viewed either either both eyes open or with the right eye closed - was:
“Yes, the question “is the wall (or the sand, in the beach case) really the shade of gray (or yellow, in the case of the sand) that it appears to be when I use my right eye or the shade it appears to be when I use both eyes, has no answer, “makes no sense”—there is no metaphysical fact to the matter to decide this “question”; but, in another way, it seems to make sense.  It takes reflection, however brief, to convince oneself that there is no such thing as the wall (or the sand) being colorwise as it looks to my left eye as opposed to its being as it looks to my right eye. It seems, at least for a moment, as it something may “really be” that color.  But there is no such thing as that color!   The color, or better the exact shade of gray or yellow or whatever,  that the wall seems to be when I use my right or left eye isn’t the sort of thing that a color on a paint chart is; the wall could really be, say, purple-gray32, but there is no such thing as it’s really being “gray*”, where gray* is the “shade” that the wall “seemed to be” when I used my left eye to view the wall on that occasion.  Subjective colors are impossible colors.  Like an Escher building, they seem to be real and simultaneously to be impossible. As long I can remember how the “gray*” wall looked, I can say truly that “it looked gray*”, but “gray*” occurs intentionally, not referentially, in “looks gray*”; there is such a thing as “looking gray*” to a person at a time, but no such thing as really being gray*. Subjective colors aren’t colors; they are Escher colors.

Obviously, my friend misremembered the claim that there is “no such thing as really being gray*”, not only by forgetting that it was gray and not green, but my omitting the “*”. There is such a thing as being gray, but no such thing as being gray*.
But what is “gray*”? The short answer is that there is no such thing. The longer answer is that, in “looks gray*”- an expression I can use to describe a color experience as long as I remember what that look was[1] - “gray*” is, in scholastic terminology, syncategoramatic. It contributes to the meaningful denoting expression “looks gray*” – which denotes a subjective look – without denoting anything on its own. That’s  why there is no such thing as being (to shift the example) green* but absolutely there is such a thing as being green. Don’t lose the star!

The importance of distinguishing colors from color looks
It seems to me that a major reason that my friend gets me wrong is that, like Russell, in Problems of Philosophy, he conflates colors and color looks. Russell wrote:

“To make our difficulties plain, let us concentrate attention on the table. To the eye it is oblong, brown, and shiny, to the touch it is smooth and cool and hard; when I tap it, it gives out a wooden sound…but as soon as we try to be more precise our troubles begin. Although I believe that the table is ‘really’ of the same color all over, the parts that reflect the light look much brighter than the other parts, and some parts look  white because of reflected light. I know that, if I move, the parts that reflect the light will be different, so that the apparent distribution of colors on the table will change. It follows that if several people are looking at the same table at the same moment, no two of them will see exactly the same different distribution of colors….” (p. 8, 1912 edition)

Here Russell moves immediately from a difference in “the apparent distribution of colors”, to “not the same distribution of colors”, that is, he takes a difference in apparent colors, or color looks, to be ipso facto a difference in actual colors. And two pages later Russell writes,

“When, in ordinary life, we speak of the color of the table, we only mean the sort of color it will seem to have to a normal spectator from an ordinary point of view under usual conditions of light. But the other colors which appear under other conditions have just as good a right to be considered real; and therefore, to avoid favoritism, we are compelled to deny that, in itself, the table has any one particular color.”

In my Bastille Day post (“The Manifest Image Is Not Wrong”), I wrote that this sort of view leads to a wholesale skepticism about the veridicality of what Sellars famously called “the manifest image. In Russell’s case this “leading to” is immediate. The very next sentence in Problems of Philosophy reads: “The shape of the table is no better. We are all in the habit of judging as to the ‘real’ shapes of things, and we do this so unreflectingly we come to think that we actually see the real shapes. But if our table is ‘really’ rectangular, it will look from almost all points of view as if it had two acute angles and two obtuse angles.” (He makes similar points about texture, solidity, etc.) And just as he concluded from the fact that the table has different color looks when viewed from different positions, that has “no one particular color”, so he now concludes that “the ‘real’ shape is not what we see” (page 11), and, further down the same page, “The real table, if there is one (sic), is not immediately known to us at all, but must be an inference from what is immediately know.”
 (Since none of the properties of the object can actually be seen or felt, the “object” becomes an inferred unobservable.)

The answer to the question in my friend’s first paragraph is that I am saying “the ‘greenness’ that I can successfully ascribe through repeated experience of my lawn as color constancy to be itself a physical property of the object in a particular state” and I am also saying (his second paragraph, but I have intentionally deleted the word “other”) “physical properties of the object cause me (and most others with my kind of eyes) to see light of such and such a frequency in such and such a scatter under such and such an illumination as the same green (more or less) as my lawn was yesterday - given that it has rained on both days - which is good for the garden in this heat - even if the look of it is different from morning to evening, from day to day.  This would mean that green objects have the same or similar physical properties” – BUT where he continues “but not necessarily that these properties are in and of themselves green, just green inducing to my kind of eyes” I would say that a particular distribution of those properties (technically, a reflectance profile) is identical with being (physically, really, green [in hue, neglecting here saturation and brightness]).  (That properties can be identical even though the concepts expressed by the corresponding predicates are quite different is something I first argued for and applied to the philosophy of mind in a paper published in 1967[2].) In sum, I believe that hues are identical with reflectance profiles, and that this identity is an empirical one, an identity we discover through theory building and confirmation.

But this would, of course, be absurd, if hues were identical with subjective looks like gray*. (Russell’s “apparent colors”, which he later says are in a “private space”).  But they are not. What looks are, and the distinction I draw between objective looks and subjective looks will be taken up next in this series of posts.

Epistemology
To close, I need to say a word about my difference with Russell over epistemology.
[I discuss these differences in more detail in “Naïve Realism and Qualia”, forthcoming in Adam Pautz and Daniel Stoljar (eds.) Themes from Block (MIT)]
Russell takes it that perception starts with sense data. That is why things in the environment can only be inferences.  I take it that we are essentially embodied creatures, and our knowledge starts with transactions between our bodies, including our brains and sense organs, and the external environment. Perception (as Tyler Burge has recently emphasized in his path-breaking book The Origins of Objectivity) involves representation of objects and features of the environment by perceptual systems; and our perceptual systems do not begin by examining the organism’s own qualia. And the properties our perceptual systems represent are not dispositions to produce qualia. I am a functionalist, but my functionalism today is a liberal functionalism[3]: the functional states involved in perception are not computational states, as I once thought, but object-involving states, states with “long arms”. If knowledge were something that begins in “private spaces”, as Russell held, there is no way it would ever get outside!












[1] In a terminology Ned Block uses, I think in “Wittgenstein and Qualia”, “looks gray*” is  ineffable, meaning by that, not the in principle ineffability that philosophers rightly view with suspicion, but that there is at present no name for that look in public language, nor, since it is a purely  subjective look, any way of introducing such a name until we know more about the neural correlates of the various subjective looks.
[2] “Psychological Predicates.” Art, Mind and Religion, ed. W. H. Capitan and D. D. Merrill (Pittsburgh, Penn.: University of Pittsburgh Press, 1967), 37-48. Repr. as “The Nature of Mental States” in Mind, Language and Reality (1975), 429-440.
[3] For an explanation of the term “liberal functionalism” see chapter 3, “Corresponding with Reality”, of my Philosophy in the Age of Science

1 comment:

  1. Love this post. The Sellarsian point that "x looks red" does not mean "x has the power to produce the sensation of red* in ordinary percipients" must (apparently) be made again and again (and again). I only wish you had also made this point in your contribution to the Block book, because I don't think Block has ever quite gotten it himself--and you come off as being on the other side of this divide in that paper.

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