Sensing Depth through Vision and Touch in Architectural Space

A dissertation submitted in partial fulfillment of the regulations for the Degree of Master of Arts in Architecture and Critical Theory in the University of Nottingham, September 2011.


New technologies especially development in design tools are seemingly increasing the distance between the architect, the users and the finished building. More often than not, the design of a building is dominated by the visual aesthetic look without much concern to other senses such as touch.

The challenge for architecture nowadays is to deliver a design with consideration for meaningful perceptual experience and thoughtfulness with regard to the body’s sensory systems.

The first objective of this dissertation is to understand the relationship of vision and touch with depth perception through mediation of light.

The second is to identify the possibilities for enhancement of architectural space experiences and meanings by using results obtained from the first objective.

The research of this dissertation is conducted through analytical reviews on theories and studies from philosophy, psychology, and biology with writers such as Merleau-Ponty, Descartes, Berkeley, Levin and so on. Finally, there are two case studies which are used to examine the results from the discussions of the topic.

The dissertation concludes that our conception and perception of architectural space and depth can be enhanced and can exceed beyond the physical realms when visual and haptic sensory systems are taken into the consideration and emphasis is placed on the design’s process. This can lead to the creation of aura of the depth in architectural experiences. Furthermore, there is also a scope for improvement in kinetic depth effect for future research in this topic.

Table of Contents

Chapter 1: Introduction

Chapter 2: Understanding the Relationship of Vision and Touch

Chapter 3: Sensing Depth through Vision and Touch

Chapter 4: Sensing Depth in Architectural Space

Chapter 5: Study Case: An Analysis on Architectural Project

Chapter 6: Conclusion and Future Development



Depth of field: the range of distances in object space within which an observer is unable to detect image blur due to misaccommodation.

Depth of focus: the range of distances in image space within which an image appears in focus.

Depth perception: the visual ability to perceive the world in three dimensions and the distance of an object.

Depth sensation: the ability to move accurately, or to respond consistently, based on the distances of objects in an environment.

Haptic: relating to the sense of touch

Kinaesthesia: the sensation of movement of body and limbs. Relating to sensation originating in muscles, tendons, and joints.

Kinetic depth effect: depth is perceived when observing a rotating two dimensional figure, object is perceived as rigid rather than a series of lines, depth is also perceived due to the stereokinetic effect

Motion parallax: dynamically changing pattern of light on retina, things nearby seem to move quickly and things far away move slower

Perspective: parallel lines converge to a single point

Proprioception: perception of the position, state and movement of the body and limbs in space.

Size gradient: object which are farther away smaller than objects which are closer

Tactile: related to the sensation of pressure rather than temperature or pain.

Texture gradient: texture becomes denser with distance from viewer

(Source: Braunstein-1976, Howard-a2002, Paterson-2007)

List of Illustrations

Figure 1: Human senses …5

Figure 2: Structure of retina …6

Figure 3: Structure of the eye …6

Figure 4: Structure of the eye …7

Figure 5: The changes of eye’s lenses and position when seeing object

with different distance …7

Figure 6: The rotation of the eye when seeing moving object … 8

Figure 7: Experiment for mapping microsaccades – eye movement

when looking at face …9

Figure 8: Axis and planes of the body …19

Figure 9: Spot as foreground on page …22

Figure 10: Experiment on eye movement and focus in seeing building …31

Figure 11: Colours of Shadow …33

Figure 12: Colours of Shadow …34

Figure 13: The changes of light contours in surface …35

Figure 14: Entrance Hall, Thorvaldsen’s Museum, Copenhagen …39

Figure 15: Site Plan, Church of the Light …42

Figure 16: Interior 1, Church of the Light …42

Figure 17: Axonometri, Church of the Light …43

Figure 18: Interior 2, Church of the Light …43

Figure 19: Plan, Bruder Klaus Field Chapel …47

Figure 20: Section, Bruder Klaus Field Chapel …47

Figure 21: Exterior, Bruder Klaus Field Chapel …48

Figure 22: Entrance 1, Bruder Klaus Field Chapel …49

Figure 23: Entrance 2, Bruder Klaus Field Chapel …50

Figure 24: Opening, Bruder Klaus Field Chapel …51

Chapter 1: Introduction

Initially, in inhabiting our built environment, we constantly attempt to relate and understand space by relating it to certain objects or signs. We see objects in space and we make sense of them by attributing them with nearness or farness from other objects. This spatial-relations model is applied unconsciously by means of our perceptual and conceptual systems. Being in the world, consciously or not, we are always orienting our bodies toward another object in our living environment – furniture, rooms, and buildings. This orientation is based on body-centred coordinates and every time we move, we move with respect to our body and its relation to other objects by determining their position in space. This is accomplished by directing our eyes to gain visual sensations to see the object and to reinforce our sense by touching the objects. Referring to Merleau-Ponty’s notion on reversibility, when we are locating ourselves in the space of building, the perception we have of the object’s location in the space is also presented back to us as the perception of ourselves being located in the world. We perceive the object as within our reachable area, and we are aware of our limbs and bodies as being capable of reaching the objects. As we experience and use the building, what is being stimulated is not simply our vision, but also our sense of touch as we walk and touch the ground, as we hold the handrail and open the door. It is a combination of visual and haptic systems working simultaneously to create kinesthesia and the sense of movement, and proprioception, the sense of body position and orientation towards the building.

There is no artistic or architectural experience without the merging of the space and the viewer’s sense of self. The task of architecture is “to make visible how the world touches us”, as Merleau-Ponty writes of the paintings of Cézanne (Pallasmaa 2009: p.128).

However, today the visual sensory system has become particularly dominant in the modern world, aided by new technologies such as the internet and Computer-Aided-Design software. Visual dominance also influences architectural design as many of our living environments seldom acknowledge the other senses. The modern mediated gaze separates us from experiencing the architecture as the viewer becomes only “a spectator of images projected on the surface of the retina” (Holl 2006: p.29). A warning is given by Geoffrey Scott for architects “not to accept a standard of architectural beauty derived from visual criteria alone” (Bloomer 1977: p.32). The challenge of architecture is to provide for the function needed whilst stimulating the meaningful perceptual experience for the users in response to particular sites and circumstances. Juhani Pallasmaa points out that architectural experience, including qualities of matter, space and scale, is constituted by all our sensory systems which interact and support each other. He quotes Merleau-Ponty’s stating that through our sight depth, speed, softness and hardness of objects emerges (Holl 2006: p.30, Malnar 2004: p.159). A building must be encountered, approached, confronted and experienced to its maximum function with our bodies’ actions and reactions which determine the connection between them. Steven Holl points out that the reality of architectural experience is based on the tectonic language of building and the comprehensibility of the act of construction to the senses (Holl 2006: p.35). Architecture through itself offers the tactile sensations of textured surfaces, the experience of light and shadow’s movement, the smell and the sounds of space, scale and proportion. The building speaks through the silence of perceptual phenomena because “only architecture can simultaneously awaken all the senses – all the complexities of perception” (Holl 2006: p.41, Malnar 2004: p.25). A building is not designed merely to be seen, therefore other sensory stimulation must be considered as part of the source for design ideas as is shown in our case studies later. The question is raised as to whether we should put forward the engagement of sensory senses as the more important factor to consider when we design our built environment and in our design because up to now it has rarely been fundamental in the design process. If so, then what sort of architecture will be produced from this awareness of the interaction of the sensory systems such as vision and touch? With all of this in mind, the key question addressed by this dissertation is how and in what way vision and touch can enhance the quality of depth perception in architectural space, particularly through the mediation of light. Indeed, most importantly it questions the meaning of depth in architectural space regardless of its physical dimensionality.

The purpose of the dissertation therefore is to suggest a distinct framework of thinking to help construct ideas and meaning in the design process. The aim is to examine the relationship of vision and touch in the development of bodily awareness, to explain the notion of perceptual depth, and to investigate the possibilities of deeper and varying levels of meaning which can be attached to spatial depth perception. Among the aims of the dissertation is to develop the connections between these factors. The topic is important in order to provide an understanding of the phenomenon of depth perception in space and the enhancement of it by the use of light. Previous researches and writings on this topic have been conducted; however it is likely that they were not specifically discussing the relationship between vision, touch, and light in spatial depth perception. It would be interesting to see how the architects create spaces which have different perceptual meanings by using light as a means to see and feel the space.

The research method adopted begins by examining variants theories and points of view from different disciplines such as philosophy, psychology, and biology in order to develop a better understanding of the research questions, and then, the results are analysed in two case studies of architectural projects from two different architects from different cultural backgrounds.

Thus, the first objective of this dissertation is to identify the relationship of vision and touch and its significance in depth perception. The second is to evaluate its possibilities and implementation in architectural space. Chapter 2 provides an explanation for the understanding of the relationship of vision, touch and body. Chapter 3 explains the conception of depth and how its perception relates to vision, touch and movement. Following this, chapter 4 contextualises the connections and findings from previous discussions regarding architectural space. Chapter 5 shows how they have been used in architectural space in two case studies which helps give further insight into our discussion. Finally, chapter 6 summarises the discussion and draws conclusions whilst recommending some future implications of the design.

Chapter 2: Understanding the Relationship of Vision and Touch

Our body is in constant interaction with our built environment as we create places for the basic needs of protection which “at its beginnings all architecture derived from this body-centered sense of space and place” (Bloomer 1977: p.5). All of our experiences of living in a three dimensional world cannot be separated from the presence of the body and its sensory organ’s experiences and this may constitute our spatial understanding in the building. By our mind’s consciousness, we locate and limit our bodies in the tangible boundaries surrounding the space which we inhabit.

Since Aristotle, senses have been known consist of sight, sound, smell, taste and touch. However, the psychologist, J.J Gibson suggests new classifications and categorises the senses into visual system, auditory system, taste-smell system, basic-orienting system, and haptic system (refer to figure 1). To begin, this chapter provides an explanation for how the senses particularly vision and touch work. Each of the sections is divided into discussion of these two senses and their relationship. The vision part is evaluated from the physiology and philosophy stand point, as well as touch. Next, we discuss their connections with our body and mind awareness. The aim is to give an understanding of the senses relationship which is important for the discussion segment of the next chapter.


Figure 1: Human senses (source Malnar 2004)

2.1. Vision

2.1.1. Eye, How can we see

When it comes to the discussion of vision, it is necessary to know how the related organ, the eye works. All of our abilities to see are enabled by the stimulation through retina which is connected to the brain by the optic nerve consisting of millions of light sensitive receptors, called rods and cones (refer to figure 2). These cells are specifically adapted to transmit signals containing information to the brain when they are exposed to the light. Other parts of our eye are the cornea, the lens and the pupil which, also play crucial roles with regards to our vision (refer to figure 3 and 4). In order to help focus the image, the eye changes the shape of its lens by pulling or relaxing the tendons which hold it so that it goes from more spherical for near objects to flatter for far ones (refer to figure 5). Meanwhile, the diameter of the pupil is changed to adjust the amount of light entering the eye as light is necessary for stimulation at the cornea interface.


Figure 2: Structure of retina (source: Gregory, 1966)


Figure 3: Structure of the eye (source: Ronchi, 1970)


Figure 4: Structure of the eye (source: Howard, 2002)


Figure 5: The changes of eye’s lenses and position when seeing an object at different distances (source: Gregory, 1966)

It is equally important to know that when the eye explores our visual surroundings, it rolls around smoothly with continuous movement (refer to figure 6 and 7). David H. Hubel indicates that “what our two eyes in fact do is fixate on an object: we first adjust the positions of our eyes so that the images of the object fall on two retinas; then we hold that position for a brief period before our eyes jump to a new position by fixating on new target” (Hubel 1988: p.79). However, he also makes another counterintuitive finding stating that “when we look at a stationary scene by fixating on some point of interest, our eyes lock onto that point, as just described, but the locking is not absolute. Despite any efforts we may make, the eyes do not hold perfectly still but make constant tiny movements called microsaccades” (Hubel 1988: p.81).


Figure 6: The rotation of the eye when seeing a moving object
(source: Gregory, 1966)

In addition to Hubel, in 1952 scientists from Brown University and Reading University, find that by stabilising an image optically and artificially on the retina in order to fixate it and prevent any movement of the retina causes vision to fade away after a while and the sight becomes blank. Conversely, moving that image even slightly causes the spot to reappear on the retina (Hubel 1988: p.81). Certainly, microsaccades are required in order to see the stationary objects constantly. It is identified that the cells, with their sensitivity to movement, are involved in this complex process causing microsaccadic movements which are apparently random in direction. This type of eye movement seems very useful to detect movements of objects contrary to a static background. It is confirming the movement’s direction and position. Our eyes follow the moving object relatively to the background by locking and tracking it. There are also other types of eye movement which include stabilisation of the image on the retina as the head moves (parallax) and convergence of the visual axes on a particular object. However, the most important type is the stereo vision system. Our vision is a stereo vision which is produced by looking at objects using two eyes at the same time with the brain comparing the images of a scene from the eyes and producing depth sensation. The same system is applied in three dimensional movies nowadays.


Figure 7: Experiment for mapping microsaccades – eye movement when looking at face (source: Hubel, 1988)

2.1.2. What is Visibility

All of the above the explanations for how the eyes can see, leads to the discussion of vision and what makes our vision become understandable, perceivable and have meanings to us. Vision, for David M. Levin, is a matter of capturing and focusing whatever the substances or the objects are in front of the eyes as visual sensory organs and bringing it directly into the view of retinal process. It also covers the notion of “horizon” or “background” which unifies the field of vision, without considering itself as an object within the field (Levin 1993: p.96). However, the way we see and perceive are not only determined by seeing clearly the objects before us, instead rather by attending to what is not directly there before our eyes, indeed not directly present before us at all (Levin 1993: p.97).

According to Levin and Merleau-Ponty, vision itself implies an observable distance between the observer and the object observed, and for Berkeley, distance is not something immediately visible (Levin 1993: p.99). However, the object of sight is there before us and becomes visible to our eyes. In fact, as Steven Holl explains by referring to Robert Irwin, it can be elucidated that object’s visibility and invisibility’s unite in the understanding of seeing and not-seeing, of how we actually perceive or fail to perceive” the visible object (Holl 2006: p.63). Merleau-Ponty through his example of our right hand touches our left and at the same time the right hand is touched back in reply, suggests that vision is reversible between itself and the world thus in order to see the world, one must be capable of being seen and visible for another’ (Johnson 1993: p.48, Vasseleu 1998: p.52). The union of visible and invisible is being studied in detail by Merleau-Ponty and for him, our vision is not concretised and limited by a visible thing but emerges from our understanding and the visibility of depths from the surroundings. Even so, visibility cannot become “visible” without the consciousness of our mind as pointed out by Arthur Zajonc. He states that sight only is not sufficient for the objects to become visible and perceivable by us, yet sight needs an “inner light,” with which it can transform the sensation into a meaningful perception. Indeed, even when the brain’s cells respond to visual stimuli, it does not mean that it participates in perception directly (Levin 1993: p.85).

2.1.3. The Significance of Seeing Light

Next, regarding the discussions of vision and the visibility of the object, light becomes essential in experiencing visual phenomena where light is a component of visibility which enables us to see an object. This is outlined by Descartes who states that “if an object is in the field of vision of an observer, and if the object is sufficiently illuminated by light and no other hides or obscures the object, then the observer will see the object as it really is, with all its detail, and will be able to distinguish it from other objects” (Lakoff 1999: p.396). Light can be considered as a medium that offers knowledge and visibility of objects to represent visual certainty of reality which is stressed by Cathryn Vasseleu who believes that “seeing light is a metaphor for seeing the invisible in the visible” (Vasseleu 1998: p.3). In the same way, Plato suggests that light is an invisible medium and becomes understandable as an idea in the objects that are made visible or brought into existence by its presence. Further, the role of light in our vision is also analysed by Merleau-Ponty. Indeed, for him, the eye’s role in vision is closely related with the carnality of the light which he sees as a substance experienced by the body’s sense of vision whilst acting as a background of sensibility to support our gaze (Vasseleu 1998: pp.45-46). Hence, it is through our mind that our gaze has the capacity to make sense of the light in order to give meanings to objects seen by our retina which it receives the figure upon it by stimulation of the light. It becomes clearer when Vasco Ronchi identifies that light is a movement of energy in the form of wave or photons reaching the retina to stimulate it, resulting in impulses being transmitted to the brain, to the psyche, and it evokes a meaningful image of the object but not before that (Ronchi 1970: pp.267-268). It is understandable as a contact matter between retina as receptor and substances of energy which consists of the reflection of objects that resembles itself and becomes meaningful through the system in our brain.

However, it is noticeable from Descartes’s statement that what reaches the eye and brain from the objects we see are not the physical image reflections that imprint in our retina. Also, it does not mean that there is something in the objects we see which resembles the ideas, sensations, or images that we have of them. All that reaches the brain from external objects, according to Descartes, are the “corporeal motions” of our nerves which have been triggered by the light from objects hitting the eye and which in turn stimulates the soul to produce certain sensations or images which are “innate” to the mind and bear no similarity to the corporeal motions themselves or to the objects that trigger them (Levin 1993: p.102). Further, Descartes explains the nature of light by investigating the differences between the sensation of light and its cause with the latter being identified as “the idea of light which is formed in our imagination by the mediation of our eyes” (Levin 1993: p.71). If the idea of light is perceived similarly to the object itself, it is because light stimulates the retina as usually it would do. The eye is misled by an objectless perception but somehow it does not affect the idea of the world whereas there are objects in the world which stands oppositely with other objects outside themselves as the “other objects are only reflected light rays which happen to have an ordered correspondence with the real thing” (Merleau-Ponty b1964: p.170). Indeed, Merleau-Ponty explains in his writing that light, shadows, reflections, and colour are not real objects and have only come into concrete substance through visual existence (Merleau-Ponty b1964: p.166).

Moreover, along with discussions on the significance of light in our visual system, Merleau-Ponty develops a term named chiasmic light which has a lived reality in seeing rather than being a coincidence or a clarification of anything. Merleau-Ponty accounts for visible and invisible light based on his distinction between the visible and the invisible notions. The distinction between visible and invisible light, also known as “lux” and “lumen”, where “lumen” (equated as the invisible light) refers to the physical movement of invisible rays of light whose perfect linearity is the essence of illumination and requires no organ of sight. The passage of lumen is transparent and unperceivable and exists independently of any material assistance. In addition, “lux” (equated as the visible light) refers to the phenomenon of light, or light as it is experienced in sight, composed of color, shadow and visible qualities. Within this in mind, Merleau-Ponty, continues with discussions regarding the distinction between the “real light” of scientific understanding and the “phenomenal light” as a qualitative experience. This distinction demonstrates the inability of light to distinguish between the two notions of light objectively where he asserts that it is impossible to differentiate between scientific and naïve perception, because both are ultimately corporeally based (Vasseleu 1998: p.42). In the same way, Levinas also makes a distinction between light in daylight and phenomenological light at night. The light at night is understood as a loss of visibility and the disappearance of objects from the condition of being seen caused by the absence of the light (Vasseleu 1998: pp.83-84). In Levinas’s notion of vision, night is crucial in that it sustains the transparency of light which light is not an absolute certainty. Levinas’s night differs from Merleau-Ponty’s chiasm of light in term of night’s invisibility breaks open the indeterminacy of phenomenological light. Night reveals the limits of phenomenology in the body’s carnality where light is the totality of the position we find ourselves in (Vasseleu 1998: p.86). Light and darkness represent the dialectic notions that can exclude each other whereas the light is absolutely influences the existence of darkness, which dispels it once light is present.

In terms of the significant role of light in vision, a discussion about light also involves the relationship between vision and tactile senses in ways that challenge the traditional distinction of these senses. With regards to these double intertwining terms, vision judges the distance from the object outside itself and gives the sense of objective certainty and freedom, while the tactile faculty gives the sense of closeness, intimacy and intuition. In its sensible dialectic whereas both feeling subject and object are affected, tactile perception is defined as a loss of objectivity in relation to the infinitude of vision’s scope. Our body becomes reference in the sensing of meaning of surfaces as it is unexplained.

2.2.Touch: Sensitivity and Movement

Our body is affected by the environment around us which gives tactile impressions to the skin covering the entire surface of our body. Through our skin we can gain information and knowledge of the world through its sensitivity of the heat of the sun, the breeze of the wind, and the cold of the rain. In the skin, stimuli are applied directly to different locations so that no special devices are required. The skin itself has the epidermis layer which houses the tactile system which consisting of an enormous number of sensory receptors receiving stimuli such as nerve endings and cells connected to the brain. Our skin is the element of our touch as part of sensory system which is classified into five sensations: pressure, warmth, cold, pain, and kinesthesis or sensibility of motion. Besides the initial term of touch, J.J Gibson suggests a new classification of touch which the haptic system consists of. Indeed, the sense of touch is reconsidered to consist of the entire body rather than simply hands as the instrument used for sensing the world. The haptic sense is recognised as a system that incorporates all sensations including all those aspects of physical stimulation which involve contact both inside and outside the body (Bloomer 1977: p.34). Another important system mentioned by Gibson in order to explain his classification is proprioception, which is a sense of the positioning and location of body-parts in relation to other parts of the body whereas a haptic spatial representation is established through the combination of tactile and kinaesthetic movement. Among several aspects of haptic sense, it is also equally important to consider two other aspects of the haptic system here. These are kinesthesia, or kinesthetic perception, and spatial extension which refers to our ability to expand our sense of touch beyond our physical limits. Kinesthetic perception particularly relates to the movement of our body muscles which provides sensory information to our brain. In this case examples of such movement include our attempts to focus eye muscles, muscles in the tongue as it rolls touching our teeth, in the fingers as we squeeze something, or in our leg as we walk. Most importantly, what we get from the kinesthesia aspect is the highly informative data that the muscle collected by its movement which provides us with information about distance, material, texture and so on. The haptic system informs us about the floor, tread, and handrail surfaces as described by Joy M. Malnar when she cites Friedensreich Hundertwasser who states that “people also have a sense of touch in their hands and feet” (Malnar 2004: p.148). Thus, it can be elucidated that when kinesthesia is coupled with active touch, the information is increased, allowing us to become aware of the surface qualities of the path we are on (Malnar 2004: p.146). In fact, touch relies on movement for its full expression rather than being static and adhering to another object’s surface. For instance, if we touch a surface for a certain time statically, it is likely that we cannot feel the touch itself. The stimulation loses its power of sensation and stops giving more information, but then appears again as soon as we move our hand and making a rubbing movement.

For the reason above, therefore, the relationship between touch and movement also evokes a kind of what we call surface and textural sensitivity. It gathers information and perceptions through hands-on experience. As an example we can refer to Malnar who cites from Rasmussen and states that “by recording their impressions of the various materials they worked with, the students gathered a compendium of valuable information for future use. The tactile sense was trained in experiments with textures systematically arranged according to degree of coarseness. By running their fingers over the materials again and again, the students were finally able to sense a sort of musical scale of textural values” (Malnar 2004: p.145). Thus, with consideration of the physical sensation and movement repetition which provides us with perception of the object, it presupposes that there is a “skin memory” which can be learned and collected through sensitivity in the texture we feel in our brain memory as shown by Ashley Montagu who believes that “the skin carries its own memory of conditions experienced in the remote and immediate past” (Montagu 1978: p.3).

2.3. The Relationship of Vision, Touch, and Body Awareness

2.3.1. The Relationship

“The skin is the oldest and the most sensitive of all our organs, our first medium of communication, and our most efficient protector . . . Even the transparent cornea of the eye is overlain by a layer of modified skin” (Montagu 1978: p.1).

“All the senses, including vision, are extensions of the tactile sense; the senses are specializations of the skin tissue, and all sensory experiences are modes of touching, and thus related to tactility” (Pallasmaa 2009: p.100).

Human vision has limitation on its capacity to see and focus on objects which are a certain distance from the eye. The eye cannot clearly see object in detail which are located very far or even too close to the eye and as a result these objects become blurred and out of focus. However, the inability of the eye to sense or see objects closely is balanced by our sense of touch, as we seek confirmation through direct physical contact (Jay 1993: p.8). Pallasmaa notes the cooperation between the eyes and hands whereby “the eye carries the hand to great distances, and the hand informs the eye at the intimate scale. Touch is unconsciousness of vision, and this hidden tactile experience determines the sensuous qualities of the perceived object” (Pallasmaa 2009: pp.101-102). Therefore, Irigaray argues that “without the sense of touch seeing would not be possible”. Seeing cannot emerge in tangible materiality, thus, it must be contingent on touch and not the other way round. Because it is separated from seen objects, seeing can only see without the ability to confirm beyond this. However, on other hand, touch can interact intimately without segregation with another and contact with self. Similarly, Merleau-Ponty himself, places emphasizes on the intertwining of visible and tangible objects as the body is perceived as a reflection of vision which is experienced by means of touch. In touch, it gives certainty and solidity to what sight can only perceive from a distance. This has already been embedded in the Christian heritage, when Thomas must physically touch Christ’s wounds to make certain his sight is doubtless. Thus, Merleau-Ponty ventures that the visibility of the world is restored through the hand by giving an example and alluding to when a correlation happens between the things and the blind man’s hands refers to Cartesian concept of vision, and between his hands and thoughts as well as the correlation of the things and the eyes, and the eyes and vision then the visibility of the world can emerge as a result (Merleau-Ponty b1964: p.170). This view is also supported by Patterson who indicates that by “adding hands (and feet, indeed) to the experience of the eye, this is as much a literal remembering as a remembering of the body, that is, adding once again the concrete experience of hands and feet to the abstracted visualism of the eye” (Paterson 2007: p.9).

Other interesting facts regarding the relationship of vision with touch are referred to in several cases studied by M. von Senden and Oliver Sacks. Cases in Sacks’ book, The Mind’s Eye, shows how the eye connects to our brain and to our sense of touch. Howard Engel, a writer, found that one morning he simply could not read or recognise words in a newspaper. All the words seemed as if they were written in foreign script. He was examined and was diagnosed as having had a stroke which affected part of the brain’s visual system. However, he did not lose his ability to write. The writing seems normal to him but he could not read a single word as he was not able to recognise it. This is called “alexia sine agraphia” where a patient after suffering a stroke becomes unable to identify familiar objects visually. People who are suffering from this can have normal vision, colour sensitivity, and so on – however they are totally unable to recognise the objects they are seeing. However, after several months he began to learn how to deal with his inability. He learned to recognise the words he saw by tracing the outlines of the letter with his hand and at the same time doing the same thing using his tongue to touch the teeth and the roof of his mouth tracing words’ shapes as he read. He replaced reading and his ability to recognise what he saw, by a sort of writing with muscular movement and sense of touch. This is similar, to the problems experienced by blind people when they are reading braille; they read it with their finger which causes strong activation of the visual parts of the brain. Such activation by touching, even in the absence of any input from the retina, may constitute a crucial part of the neural basis for the mind’s eye but in Engel’s case he still has his vision. He combines his vision with touch and muscular movement to regain something that he has already known but has through damage to his brain. Sacks refers to another case in his book, where a patient lost his sight and experienced a decreasing of visual imagery and memory. Finally, he suffered a virtual loss of his sight – a state called “deep blindness”. It is not only a loss of visual images and memories but also includes the idea of seeing, and even perceptions like “here,” “there,” and “facing”. He could no longer visualise how the numeral 3 looked unless he traced it in the air with his finger. On the other hand, there are several cases where blind patients after losing their sights have never lost their visual images or memories. They develop a mental picture or visual imagery in their mind. They construct a virtual visual world which enables them to complete physical activities such as typing, fixing things and so on. They are likely to see with their mind. Touch has been treated as a differential form of knowing, by supplementing the vision with different visibility. Touch is very important for giving object-meaning to vision.

2.3.2. Being in the World: Body Awareness

Quality, light, colour, depth, which are there before us, are there only because they awaken an echo in our body and because the body welcomes them (Merleau-Ponty b1964: p.164).

Discussions above detailing the relationship between vision, touch, brain and body show that they are mutually supportive and connected to each other. Instead of just “seeing” the retinal image, the brain also functions in relating signals from the eyes to the physical objects, as essentially known by touch (Gregory 1998: p.6). Visibility of the object as explained above can become perceivable only if it is understandable through our mind and awareness. With this in mind, Hegel explains that “vision is a complex fusion of different levels of awareness which unites and evokes human’s sensation, consciousness, intuition, and understanding blend in one particular action” (Levin 1993: p.107). In the same way, and in agreement with Hegel, Merleau-Ponty considers the consciousness of the eye and cites Malebranche who states that “the mind goes out through the eyes to wander among objects” (Merleau-Ponty b1964: p.166). He recognises from Descartes that vision has emerged from thought but for him, “it is not enough to think in order to see” as thoughts emerge as a result of what happens in the body; “it is incited to think by the body as the soul thinks with reference to the body, not with reference to itself” (Merleau-Ponty b1964: pp.175-176, Levin 1993: p.84).

Similarly, touch, in order to be perceivable and sensed must be rooted in the awareness of the body’s presence. For this reason, Juhani Pallasmaa evaluates the significance and consciousness of the hand in his book The Thinking Hand. Indeed, he highlights that hands provide the most accurate part of our touch perception especially the fingertips, due to the concentration of nerve endings. He quotes from Immanuel Kant that “the hand is the window on to the mind” (Pallasmaa 2009: p.25) and shows that, as well as the eye, “every motion of the hand in every one of its works carries itself through the element of thinking, every bearing of the hand bears itself in that element” (Holl 2006: p.28). The touch and caress of the hand, therefore, explains the presence of objects and the world around us through the contact of its “physical skin” which gives the awareness of touching and being touched back.

fig8-howard fig8-howard

Figure 8: Axis and planes of the body (source: Howard, 2002)

Considering the fact that vision and touch reside in the body as the container, it is important to understand the position of our body relative to the world. Significantly, Merleau-Ponty states that the body is a form of consciousness which is perceived as an embodied container where all conscious is experienced as the result of interaction with the world or environment. In other words, the body provokes a linkage and locates itself in relation to a world. In order to see objects related to their position in the world, we also supposed to know where the position of our body in the world. This recognition is based on our own awareness of ourselves, as pointed out by Bloomer who states that “since at the very beginning of our individual lives we measure and order the world out from our own bodies” (Bloomer 1977: p.1). Our body is the centre and the measurement of the world. How far can we perceive the world is determined by how much we come to understand our body, its position and its movement.

The significance of movement and the correlation of vision and touch form a central aspect of the orientation toward the world as vision and tactile awareness of things in the world is given via proprioceptive awareness of one’s own body. Perception is achieved by the movement of the body centred to itself but also by body movement around objects in place when the subject perceives and moves by using their limbs, therefore it provides them with awareness of their own body (Romdenh-Romluc 2011: p.89, Paterson 2007: p.30).

As a concluding remark for this chapter, therefore, the awareness of our vision and touch through the mind which are embodied in our body is useful for perceiving the world and our spatial awareness. Merleau-Ponty’s claims that the reversibility and the union of vision and touch are embedded in the movement and the crossing of the body and the world which bring the discussion of depth in the next chapter.

(to be continued to part 2……)