Mary the Embodied Colour Scientist

(Being the techno-wiz that I am, I've worked out how to add additional authors to the blog. So who's written what should now be both more obvious and less obtrusive...this is Joe, by the way.)

"Mary the Colour Scientist" is a classic thought experiment, originally formulated by Frank Jackson (1982; 1986). For those unfamiliar with it, it goes something like this:

Mary has been raised from birth in an entirely monochrome environment, although she has been provided with a wealth of scientific data on colour and colour perception. She is in fact the world expert in the field, despite having never seen colour. For the purposes of the experiment, we are asked to assume that she knows all there is to know about the physical process of colour perception. What happens when she is released into the world? The thought is that she must learn something about what colours look like, despite already knowing all the physical information about colour and colour perception. Thus, there is more to experiencing colour than just the physical process, and therefore physicalism is false.

Monochrome

There's been a huge quantity of debate about this experiment over the years, and I don't intend to discuss much of it now. Most of the replies can be found in an anthology, There's Something About Mary (2004). What I want to discuss is a potential response, from the perspective of embodied cognition, which I don't think has been discussed in any detail before.

Jackson asks us to imagine that Mary knows all that there is to know, scientifically speaking, about colour. Ignoring the fact that the sheer weight of this claim is often underestimated¹, we might want to challenge his interpretation of what this in fact means. He assumes that a fully-detailed factual knowledge of colour perception will necessarily, if physicalism is correct, grant Mary knowledge about what colour looks like. On a traditional understanding of cognition, this seems to be a fair assumption. Knowledge, including phenomenal knowledge, is just in the head, and if we knew how colour perception worked, we would be able to imagine what it would be like to have such perceptions. This is the kind of cognitive materialism that was Jackson's original target, and given those assumptions his experiment can seem fairly convincing. My opinion used to be that we had just failed to grasp what truly complete knowledge of colour perception would be like, and that, contra Jackson, Mary in fact wouldn't learn anything knew when she perceived colour for the first time.

However, another possibility has now occurred to me. What if experiencing colour were to be more accurately conceived as an embodied phenomenon, involving not just the brain, but also the visual system and other physiological responses?² If this were the case, then scientific knowledge of colour perception just wouldn't allow for phenomenal knowledge of what colour looks like. Such knowledge would necessarily be impossible to acquire without actually seeing colour, and not because of any non-physical quality, but simply because that's how colour perception works. Once we shift our focus from the brain to the body as a whole, this seems pretty obvious.

A related kind of response has been made previously, that what Mary acquires when she first sees colour is knowledge, but knowledge of a different kind to that which the scientific understanding of colour perception granted her. Harman (1990), Flanagan (1992), and Alter (1998) all make arguments of this kind. What the perspective of embodied cognition adds to these kinds of responses is a principled stance from which to argue that there is more to knowledge and experience than what goes on in the brain. A more extreme response would be to deny that visual knowledge is ever possible without a world to perceive,³ in which case we would simply deny one of Jackson's original premises, that Mary has total scientific knowledge of colour perception. Such knowledge might not be acquirable without actual experience of colour. This might seem like a cheap way out, but scientifically implausible thought experiments can't easily be given scientifically plausible responses. Once you start discussing things that can't actually happen in the real world, the need to give you a real answer sometimes becomes moot.

1. A problem which pervades many thought experiments of this kind. Whenever you're asked to consider a situation where someone has total physical knowledge of a situation, be wary. Such knowledge is way beyond the reach of current science, and might simply be impossible for any human to comprehend. I often feel that the best response to such experiments is a cautious "I don't know what that would be like, so let's withhold our judgement".
2. There's a secondary issue here, which to my knowledge has not been satisfactorily resolved. After a lifetime of monochrome experience, Mary might in fact be totally unable to perceive colour. Experiments on sensory privation during visual development suggest that, at best, her perception of colour would take a while to develop, and might never quite reach 'normal'. Oversimplifications of this kind haunt many otherwise powerful thought experiments. 
3. Gibson's ecological theory of perception, discussed at length by Rockwell (2005), might entail something like this.

• Alter, T. 1998. “A Limited Defense of the Knowledge Argument.” Philosophical Studies 90/1: 35–56.
• Flanagan, O. 1992. Consciousness Reconsidered. Cambridge, MA: MIT Press.
• Harman, G. 1990. “The Intrinsic Quality of Experience." Philosophical Persepctives 4, Action Theory and Philosophy of Mind: 31–52.
• Jackson, F. 1982. "Epiphenomenal Qualia". Philosophical Quarterly 32: 127–136.
• Jackson, F. 1986. "What Mary Didn't Know". Journal of Philosophy 83: 291–295.
• Ludlow, P., Nagasawa, Y. & Stoljar, D. (eds.) 2004. There's Something about Mary: essays on phenomenal consciousness and Frank Jackson's knowledge argument. Cambridge, MA: MIT Press.