- Shadows and Enlightenment by Michael Baxandall
Yale, 192 pp, £19.95, June 1995, ISBN 0 300 05979 5
Powdering one’s nose is a strategy for controlling the effects of light. The powder changes the reflectivity of the surface of the skin. Oily skin acts as a mirror which bounces light off at an angle equal to the angle at which it arrived; powdered skin is matte and reflects light in all directions. Powdering thus turns a bright, specular highlight (the kind you get on glass or polished metal, which moves across the surface of the object as you change your point of view) into a diffuse one. For an artist, getting to know the nature of highlights, grasping the fact, for example, that the end of a nose or a cheek, even a brown or black nose or cheek, will often be the brightest part of the face – brighter than the ‘white’ of the eye, which is, in fact, usually grey and shadowed by the eye socket – is one step on the path leading from naive to ‘realistic’ representations of faces.
Shadows and shading in pictures represent the variations in the light reflected from objects which, on reaching the eye, become the raw material of perception. Although we are good at using make-up and camouflage in order to manipulate appearance, it takes strenuous effort (what amounts to an act of suppression) to become aware of just how the perceptual material relates to such stratagems. Painters (well, some kinds of painters) must, as Michael Baxandall puts it, ‘backtrack down the channels of perception, undoing the integration of features that is higher perception’s achievement, pushing right back down to the early visual modules of brightness, colour and the rest’.
To be interested in Shadows and Enlightenment you must be interested in this kind of thing, interested, in particular, in looking at shadows. Baxandall says his book is ‘coloured by being an offshoot of work-in-progress on problems of visual attention in 18th-century thought, in modern thought and in the art of painting’. It raises very basic questions. Do we look at marks on the canvas, or the things the marks represent, or both? And if we look at both, in what sense can we be said to give our attention to, say, a patch of pink paint and, at the same time, to the Virgin’s cheek?
It helps, in reading Baxandall’s book, to be aware of the extent to which his examples from computer and cognitive science, as well as from the words and work of painters, help to define a central paradox: that if we pay close attention to variables like shadows, which are, in the ordinary way of things, perceived inattentively, our attention itself gets in the way of the process we are trying to understand. We have, in Baxandall’s words,
no clear idea of specifically in-attentive perception as a productive complement to attentive perception – attention this time in the sense of a directed, focused and constructive scrutiny in some reciprocal relation to consciousness ... ‘Attention’ effectively disables itself as a concept by reducing the ‘in-attentive’ to a negative or absence of something, rather than the active, determined and structured field in which consciousness plays.