A Fable: Mary the color scientist

Once upon a time, there was a very eminent scientist named Mary
who knew absolutely everything there is to know - literally - about the physical side of color. Mary understood that the human eye can perceive light frequencies within the rage of 4.3-7.5 x 10¹⁴ Hz of the electromagnetic spectrum. If you said “red” she could tell you the range of frequencies that comprise the color that comes into our minds when we hear that word. Mary knew perfectly how the optic nerves send their information to the visual cortex to produce the experience of seeing colors. She understood in full detail neurology and optics, diseases of the eye, practical ophthalmology, and much more besides. Her memory and understanding were extraordinary. Now, be that as it may, Mary had never actually seen colors. To be sure, she had the ability to see color, but all her life she had been cruelly confined to a room where nothing had color. Mary’s eyes had only seen things that were black, white, and different shades of gray. (Yes, this is just a fable!)

Then one day her colleagues at the Institute of Vision finally decided it was time to let Mary out of her color-challenged environment. They led her down a black hallway into a white room where on a gray table was a single red rose.

Mary gasped. She saw color for the first time and was shocked by the ineffable quality of it. She could not name the color; in fact, she could not even begin to think of a specific word to describe it.

Now the point is this: I said that Mary knew everything about color from the objective, physical point of view, but when she saw it for the first time, she knew something she'd never known before—what it’s like to see color. Or did she?

We might say that Mary experienced the reality of something she had a great deal of knowledge about. But was it just that—a new experience—or did Mary acquire any additional knowledge about redness when she saw the rose? Did her information about redness increase? What is the difference between those last two questions? And in terms of language, how can we define the word “red” anyway? How many topics from the TOK wheel are evoked by this story?

You stand awed looking at a sunset, feel dwarfed before the Grand Canyon, or gaze in silence at a million stars on a cool, clear night. Are you simply a passive receptacle of this sensory information? In what way can these experiences be said to transcend the data of our sensory perceptions, if they do at all. If they don’t, why do we feel so powerfully and intuitively that they do?

Story taken from Jackson, F. 1982 "Epiphenomenal Qualia," Philosophical Quarterly, 32, 127-136. Edited and adapted for TOK by J Henderson.

Qualia and the Ineffable Experience of Being: Three Views

When we see a red word on a page, our brain acquires all sorts of data about the wavelength of the light, the shape and size of the letters, and so on. But there is more to it than that: we also have an experience of redness, and this experience is over and above the mere data-gathering, which a computer could do equally well. This experienced red, along with experienced blue, cold, noise, bitterness, and so on are qualia, and it is very hard to give a fully satisfactory account of them. In particular it is hard to find any satisfactory place for them in the account of the world provided by physics. They are 'raw feels', we know they exist because 'there is something it is like' to see red, smell grass, and so on. (See Nagel’s essay “What is it Like to be a Bat?”)

The problem of qualia has been at the forefront of recent discussions of consciousness, but somehow it nevertheless lacks the established respectability of some other philosophical issues: it is not one of the old philosophical chestnuts chewed over since the time of Socrates. Perhaps it only began to seem a mystery in its own right once a mechanical explanation of the general workings of the mind seemed possible, though whether this perception of mystery represents enlightenment or bedazzlement remains an open question. It is certainly an exceptionally slippery issue, and most of the literature on the subject is about establishing the existence and nature of the problem, rather than solving it.

The arguments for the reality of qualia take many forms and some have become very convoluted. A clear exposition of five is given by Chalmers. All the arguments, however, depend on the basic intuition that there is something involved in subjective experience over and above the simple mechanical, physical story, something which could in principle be taken away without affecting the course of that story at all.

There are three main ways to go on qualia. The first is the Dennettian path of scepticism: there are no qualia, the whole thing is a category mistake, or some other confusion or delusion. This approach avoids an immense number of problems, but it rides roughshod over the very powerful intuitive conviction that there is something more to seeing a red object than just acquiring the knowledge that it is, in fact, red. Instead of having to explain qualia themselves, we have to explain just why so many people find their existence undeniable.

The second course is to start explaining the physical process of perception in the brain and hope that somewhere along the line it will somehow amount to, or include an explanation of qualia. This approach is particularly appealing to scientists and engineers. Let's just build the robot; if we succeed we may have picked up our explanation of qualia along the way, and if we succeed without the explanation, maybe it doesn't matter anyway; the philosophers never explained how this stuff works in human beings, either, did they? But building the robot turns out to be more difficult than it seemed; and our purely physical theories of the brain, interesting as they may be, don't seem to provide the answer. Either we end up with a purely neurological theory which, whatever may be claimed for it, does not touch on the problem of qualia at all; or we end up reducing qualia to a special kind of flag or label which plays some role in an ordinary computational physical process. There might be such flags, and they might be well worth studying, but they aren't, in the original sense, qualia, and nothing we might say about them can possibly resolve the original problem.

The third path is to accept the full-blooded version of qualia: but this involves insoluble problems. Qualia aren't part of the normal physical process of cause and effect, but speaking and writing are: it follows, bizarrely, that nothing we may say or write about qualia can actually have been caused by them, or by our experience of them. Quite how bad this problem is depends on one's views about reference and causality, but it is very bad even in the best case, and in attempting to deal with it Qualians are driven towards hopeless philosophical positions such as dualism and epiphenomenalism. So far as I can see, there is no-one who accepts the full reality of qualia and who even claims to be able to clear up the mystery completely.

Adapted from Bedtime Stories on http://www.consciousentities.com/