THE INTERRELATION BETWEEN PHILOSOPHY AND SCIENCE

In light of growing evidence in support of the dual visual system hypothesis – gathered not only from anatomical studies, but from electrophysical testing and psychological research too – it is clearly no longer adequate to think of vision as singularly tailored to the demands of perception, as Marr‟s theory (and by implication Willats‟s) would seem to suggest. The idea may owe its pervasiveness to the fact that conscious awareness is largely ventral (or perceptual) and so we tend to see the world as a collection of definite identities, or as Merleau-Ponty might have put it, we think of it as a realm of „determinate being‟. However, it seems that the philosopher may have been right in juxtaposing this form of seeing with a more primary and embodied stratum of

perception. 165 For, insofar as the dorsal stream evokes motor imagery and guides our actions, it might be said to induce the carnal phenomenology that he attributes to sight.

However, it is necessary to exercise caution in making this claim for, as Taylor Carman points out, „motor intentionality is not a neurological datum, not is it simply Merleau-Ponty‟s name for…dorsal stream processing‟. Rather it is the essential intermediary which connects our bodies to the world and which, by establishing their unity, allows our conscious activities and thoughts to gain their significance against a background of perceptual experience.166 Accordingly, it is not my intention to suggest that psychology supplies an explanation for – or indeed, explains away – Merleau-Ponty‟s metaphysical assertions. My claim is simply that science and philosophy point in the same direction by positing the existence of a more embodied form of sight. Thus, while the dorsal stream might tentatively be understood as the physiological correlate of motor intentionality, its identification does not detract from the philosophical implications of Merleau- Ponty‟s account. And in particular, it does not imply that the body is reducible to an object or that it is ultimately a complex of physio-chemical processes. In short, while knowledge of these operations may illuminate aspects of our perceptual or our aesthetic experience, their human significance may lie somewhere beyond.

165

Goodale argues that the evolutionary development of the dorsal stream predates that of the ventral stream since the brain „did no evolve to enable us to think, it evolved to enable us to act.‟ „Action Insight: The Role of the Dorsal Stream in the Perception of Grasping‟, Neuron, 47, no. 3 (August 2005), pp. 329. If this is correct then the dorsal stream can be characterised as „primary‟ in a phylogenetical sense. Bur of course, this has no relation to Merleau-Ponty‟s claim that embodied perception is the ground of consciousness.

166

Nevertheless, taken together these two modes of description supply us with a powerful tool for reassessing the validity of our commonsense assumptions. And more importantly for my argument, this scientific research lends support to Merleau-Ponty‟s criticism of the view that visual information is only made available to our motor capacities by way of an associative process.167 What classical psychology suggests, for instance, is that when I see a pen I relate this to my previous experience by way of memory and judgement. Thus, I infer

how to coordinate my movements towards it rather than having this information directly available. But the existence of parallel pathways in the brain suggests the opposite: that an integral part of seeing the pen is understanding it as a target for action, or, more generally, that perceiving motor affordances is a direct consequence of vision. This is not to say, of course, that I do not need to recognise the pen in order to select it for use. What it suggests, however, is that when I do form this plan I already possess the requisite knowledge to reach out and grasp it. Since visuomotor processing is faster than perception, actions can often pre-empt judgements of identity. For instance, when a projectile is flying towards me, I may duck before I know what it is.168

167

While this view has been held by various philosophers and scientists for many hundreds of years, it reached a peak in the twentieth century with Ivan Pavlov‟s studies of classical conditioning. Pavlov showed that the repeated pairing of two stimuli led them to be associated, thereby producing a behavioural response. This idea proved to be influential in the formation of behaviourist psychology, an approach which Merleau-Ponty constantly challenged in his work. For Merleau-Ponty‟s criticism of this view see Phenomenology of Perception, pp. 15 – 29.

168

This is to be predicted from the fact that, in order to be effective, our capacities to move and to act – and particularly to perform such defensive responses as flinching and ducking – need to be continually updated with information about the location and movement of objects in our

immediate environment. Therefore, in contrast to visual percepts which need to be taken „offline‟ in order to supply content to memory, visuomotor representations must always be „online‟ in order to keep track of real time changes (although, psychophysical studies suggest that they can be briefly encoded in short-term memory). Evidence for these different modes of processing is provided by the anatomical organisation of each visual pathway. While the ventral stream passes through several intermediary areas before reaching the inferotemporal cortex, the dorsal stream includes projections from the magnocellular area of the lateral geniculate nucleus which link to areas MT and V6 directly. Thus, according to Jacob and Jeannerod, „visual latencies in the dorsal stream (40 – 80 ms) are faster than in the ventral stream (100 –150 ms). Ways of Seeing, p. 55.

And so, hypothetically speaking, this duality of sight might also have a bearing on the way that we perceive representational pictures. That is, any image which refers to some content iconically (which is to say, by resembling it visually) may not only present us with something we recognise, but even before this, with something we know how to orientate our bodies towards. Thus, while it might seem natural to classify pictures as visual objects pure and simple, we might here have been led astray by the ostensible phenomenology of seeing – a phenomenology which pictures generally heighten by reducing the information available about depth and which the Western tradition has emphasised even further by celebrating the conjunction of the eye with the mind. But while the motor intentionality of sight may lie hidden – and indeed, while in some cases it may have been wilfully disavowed – its growing acknowledgement in the twentieth century shows that it is not beyond the scope of our conscious awareness, even if it is not transparently available to thought.

If „vision for perception‟ and „vision for action‟ are therefore so separated in normal seeing but if, however, the latter lies hidden and either takes the insight of a philosopher or the expertise of a scientist to be drawn out, can an artist also be said to perform this revelatory function? This, I want to suggest, was precisely the advance of Cézanne‟s classicism – that is, the power of his style in producing a criterion of a visual experience that the post-Renaissance tradition had systematically disavowed. And equally, I wish to propose that it was the lesson that Picasso and Braque took from his art and further developed through their invention of Cubism. What this means, therefore, is that they did not simply

consult his style in order to learn from its technical innovations (the use of

passage and the integration of foreground and background being the most often cited). Rather, what makes their Cubism truly „Cézannian‟ – and not only in 1908 - 9, but later on too – is their desire to build on his art‟s peculiar aesthetic: that is, the way it replaced visualised thinking with physicalised sight.

Nonetheless, we still do not have an adequate explanation for how this elusive dimension of motor intentionality can be transfigured into a language of form, or why its counterpart, the conceptualising tendency of vision for perception, should give rise to the particular representational conventions it does. As I intend to show in the following chapter, this will require something of a detour: an attempt, no less, to trace representation back to its very roots. In short, we shall have to consider the fundamental – and crucially, the non-arbitrary – relationship between the structure of pictures and the structure of sight.

CHAPTER 4

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