Colors and Looks (1)
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
In a previous post (“Escher Colors”, 6/11/14),
I pointed out that that colors do not look the same to all normal people, on
any reasonable construal of ‘normal’. (See
also Ned Block’s “Wittgenstein and Qualia”, in Maria Baghramian (ed.), Reading Putnam.) As I pointed out in that post, colors do not
look quite the same when viewed with one eye closed and when viewed with both
eyes open, or when viewed with the other eye closed, even when the illumination
and the distance and the angle of vision, etc., are held constant. There is a
temptation to think that the questions, “Does my right eye see such the color
of such and such as it really is?” and “Does my left eye see such the color of
such and such as it really is?” make sense, but on reflection one realizes that
they don’t. “The color I see”, as Russell would have put it in The Problems of Philosophy, isn’t a
color anything could “really be”, for if it were then “The color I see when my
left eye is shut” could be the real
color of the object, and “The color I see when my right eye is shut” could equally
be the real color of the object, but those
“colors” are not the same, and the object could not be both colors at
once. Subjective colors are what I
called “Escher colors”; phenomenologically it seems as if they are “diaphanous”,
as if each eye in turn is seeing the object “as it really is”, but it is
impossible for any object then to be both of those ways, and, given that
neither way of looking is the way the
object looks to all normal people in those circumstances, neither is there any
sense in saying one way of looking is “veridical” and the other
“non-veridical”. So I argued in that post.
But why not conclude, a friend asks,
that colors aren’t real? The “person on
the street” project colors onto the surfaces of objects, but they aren’t really there. This was,
indeed, Russell’s view, and, before him, the view of Hume as well (except that
Hume thought that objects aren’t really “out there” either, but that is another
story).
This story about how the person on
the street mistakes what is in her own mind for properties of “external things”
has not gone unchallenged. In the 18th century, Thomas Reid, Hume’s
great contemporary and rival, argued that the person on the street knows
perfectly well the difference between a color and a sensation, and he was
absolutely right. We do not think that objects change their color between 10AM
and 7PM, although the look of any given colored object changes. We don’t think
an object changes color when a cloud passes over the sun, although we are all
aware that its look changes. Most people are not aware of the variability of subjective looks, for example, that
objects that look bluish green to one person might look pure green to another,
and the phenomenon of fine shades of difference in the apparent saturation of
colors owing to differences in the pigmentation in (“normal”) macular areas
that I mentioned in Escher Colors was
unknown to even the optical technician I mentioned in that post, but that a
color has a number of different looks depending on the conditions is not news.
Reid was right, that the empiricist story makes the person on the street too naïve.
An old story, which is not as
uncharitable to the person on the street as the claim that she projects what
are really subjective looks onto the surfaces of objects goes like this: colors are dispositions to produce certain
sense data (under appropriate conditions). This story still assumes the person
on the street is confused: she thinks that her sense data are looks of objects
in an objective sense, the sort of
looks that can be recorded with a camera. According to this story, she does not
realize that what she calls “looks” are themselves sense data. But she does
know that the dispositions to have those looks is a property of the objects, and she does not agree with
Russell’s view that the objects themselves are never experienced, but at best
“inferred”.
But this story too has problems
(which I will talk about in the next post).
My interest in all this is not merely
historical. The relations and distinctions between objective and subjective
looks, objective colors, sense data (or to use the currently fashionable term, qualia), perception, experience, and
apperception, are all topics Hilla Jacobson and I have been discussing for seven
years, as we work on a planned book on apperception and consciousness, and we have eached published things that
touch on these topic (and also have
forthcoming unpublished papers on them).
In posts subsequent to this one, I plan to continue my answer to my
friend’s question, why I persist in the view that colors are real. But I can give a preliminary answer: it is nowadays a respectable (and I believe correct)
view that many (though not all sorts of) dispositional properties of
objects are explanatory and ontologically robust. Properties that enter into
explaining the survival value of various phenotypes (and hence of the
corresponding genotypes in certain environments) are explanatory and robust in
this way. And colors are such properties, as evidenced by the fact that
convergent evolution has led very different species (e.g., humans and at least one species of octopus) to develop eyes able to differentially
respond to colors. [See Gunzo Kawamura, Kazuo
Nobutoki, Kazuhiko
Anraku, Yoshito
Tanaka, and Masaru
Okamoto, "Color Discrimination Conditioning in Two Octopus Octopus aegina and
O. vulgaris", Nippon Suisan Gaikashi, vo. 67 (2001), pp. 35-39, https://www.jstage.jst.go.jp/article/suisan1932/67/1/67_1_35/_article]
I don’t believe colors are dispositions to produce
particular sense data, as will be
explained in subsequent posts. But it is plausible that they are dispositions to
affect light reflected from the objects that have those disposition in certain
ways, ways that in turn affect our eyes (and those of Octopus aegina), and
thereby enable us (and O. aegina) to identify and re-identify those objects
more easily.
Of course, if you think that things
as intuitively different and colors and dispositions (of the kind just
mentioned) just cannot be contingently identical—if you don’t think that science
can and does discover non-analytic identities between
properties—then you will reject this account of colors as physical dispositions out of hand. But
then, I have long argued, you are making a serious mistake. [See my (1970) “On
Properties”, collected in Mathematics,
Matter, and Method, vol. 1 of my Philosophical
Papers (1975).]
nice post
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