Augmented Reality and Phenomenology

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DEPARTMENT OF DISCIPLINE UMANISTICHE

Ph.D. degree Curriculum Discipline Filosofiche

M-FIL/01

Ph.D. Thesis

Augmented Reality

and

Phenomenology

The creation of “digital materiality”

and the knock-on effects of

such a futuristic potentiality

Candidate:

Nicola Liberati

Thesis advisor:

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technology is indistinguishable from magic

Hazard of prophecy: The failure of imagination Arthur C. Clarke

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Augmented reality is one of the most innovative technologies of our time and it pursues a fascinating goal: to merge the digital and the real world together.

The aims of this thesis are to improve its design and to study its knock-on effects on our everyday world and on our living body.

Augmented reality does not need an engineeristic approach only, but it also calls for theoretical studies on perception in order to reach its goal.

The thesis uses phenomenology in order to tackle this topic from a perceptual point of view because the focal point of this branch of philosophy is to analyse how the subject perceives and so it helps to understand how the subject is perceptually shaped by this new technology.

Moreover, by studying how augmented reality interacts with the subject, it is possible to provide the characteristics this technology must have in order to be a completely new technology without reducing it to mimic “old” kinds of technologies, such as ubiquitous computing.

The thesis demonstrates that augmented reality has to produce digital ob-jects instead of displaying information about the surrounding world. It shows that the objects should be perceived in a “transparent” way and it displays the parameters to be followed in order to achieve such a transparency producing a device which can easily become part of the subject’s living body. Only by following this path can augmented reality merge the digital and the real world together and become a new technology different from the previous one.

Augmented reality has to create “digital materiality”.

The second aim of the work is related to the knock-on effects yielded by this new technology and they are analysed thanks to a phenomenological aspect as well. Phenomenology does not take technology as an isolated being, but it considers technology deeply interconnected with the subject and the world. Therefore, this conception makes it possible to study how these terms are modi-fied by the variation of one of them because they are intrinsically related. More specifically the introduction of a new technology changes inevitably what the subject and the world are because they are strictly intertwined due to this three-fold relation in which they are enmeshed.

My work shows how technology in general deeply moulds our living body and our everyday world by shaping what we consider their most natural and primal bases. Therefore, augmented reality will not have knock-on effects concerning what lies on the surface of our life only, but it will deeply affect the most basic core of our living body and our everyday world too.

In conclusion it is clear that augmented reality has to produce “digital ma-teriality” and that such a creation will yield the knock-on effects of turning our world into a world dwelt even by digital beings.

Tomorrow’s world will be composed of digital matter along with the common one.

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List of Figures

2.1 White paper under a red light . . . 13

2.2 Optical glasses allow a better perception . . . 16

2.3 Internal lens . . . 17

2.4 Transparency of directionality . . . 24

3.1 Validity between Lebenswelt and the scientific world . . . . 36

3.2 Idealisation of vague objects . . . 39

3.3 Sciences’ knock-on effects on Lebenswelt . . . . 40

3.4 The naturalistic attitude is founded on the natural attitude . . . 42

3.5 The naturalistic attitude is founded on the natural and person-alistic attitude . . . 43

3.6 The “contamination” of the personalistic attitude . . . 44

3.7 Parallel between Lebenswelt/Scientific world distinction and the three kinds of attitude . . . 44

3.8 Lebenswelt-one and the vicious circle . . . . 45

3.9 Relations among attitudes and kinds of Lebenswelt . . . . 47

3.10 Relations among the different kinds of Lebenswelten . . . 52

3.11 Example of “peripersonal space” . . . 63

3.12 Relation between localised sensations and non-mediated sensations 68 3.13 Not existence of the relation between localised sensations and non-mediated sensations . . . 71

3.14 Relations between the two Lebenswelten and primary and ex-tended Leib . . . . 76

4.1 Milgram’s continuum . . . 86

4.2 Diminished reality . . . 87

4.3 Painting: Bonaparte franchissant le col du Grand Saint-Bernard 91 4.4 Three kind of objects in the painting . . . 107

4.5 The fourth possible technology . . . 108

5.1 Ubicomp’s network . . . 112

5.2 Alice and the bottle . . . 114

5.3 Relations among subject, subject’s attention, technology and per-ceived object . . . 116

5.4 AR glasses providing a textual information about an object . . . 119

5.5 AR glasses providing the object “label” . . . 120

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List of Tables

2.1 Three possible combinations of the two transparencies . . . 30

3.1 Types of relations . . . 60

4.1 Schema of two subjects in two worlds . . . 99

4.2 Schema of the immersion of the subject in a painting . . . 101

4.3 Schema representing the “immersion” of the subject in a AR . . 101

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Chapter 1

Introduction

Not much time has passed since the introduction of computers into our everyday world.

From clumsy amasses of silicon and metal, classic icons of computers used in the ’60s or even in the ’70s, computers have become something quite invisible which can be used everywhere and at any time. So small and “pervasive” that the need rises to “defend” ourselves from their hidden action with laws, restrictions and precautions.

However, computers, in their main activity, are still confined to a space inner to themselves where the subject immerses themselves in order to get information and act.

Even in “the internet era” where the concept of “the net” is broadly used in our everyday life, we still have to deal with using computers as a device which allows the subject to enter a new different world composed of moving packages of information and ruled by computer programmes.

Therefore, we have a clear distinction between two different spaces of action: one related to the world inside the computer and the other in our everyday world. This idea is changing rapidly because the computing activity starts to walk on this earth hand in hand with our common activity. Computers are not becoming devices in which the subject has to immerse themselves.

Up to now screens were the best way to visualise the information. Now, instead of screens, computers will use different devices to interact with us. They are no longer objects the subject can look at or objects which the subject has to focus their attention on.

Computers will be part of our everyday world in a more literal sense by making the whole of the everyday world as an user interface. Computers are not active in “their” world but become active even in “our” world. Our actions will be detected and analysed by invisible computers.

The efforts are aimed at bringing the digital world into our world instead of immersing the subject in a new world.

Especially augmented reality seems to be the most important innovation on this field because it has the potentiality to literally merge the digital world and our everyday world.

Therefore, a rigorous analysis of augmented reality is mandatory.

We are facing a revolution in computer science because we are moving from devices which produce two separated worlds, our everyday world and the one

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internal to the computers, to devices which act and “live” in our everyday world directly.

In order to study this revolution, we are going to use a phenomenological analysis. Phenomenology studies the way the subject perceives and so it is the most appropriate one for tackling a change concerning perception.

This revolution entails not only a mere technical engineeristic level on the devices, but it is a revolution in the way the subject perceives computers and the way the subject perceives through them. That means the “technical engineering level” needs a wider analysis of this subject in order to achieve better results in their goal to merge the computer into our everyday world. It has to open itself to different approaches.

It is a problem concerning the relations between the subject, technology and our world such devices want to produce which is the field of research related to phenomenology and post-phenomenology.

Moreover, the introduction of a new technology, which creates a new relation between these elements, entails also a modification of such elements according to such new relations.

The technology is not inert, but it shapes the elements to which it is related. and phenomenology allows us to analyse this relation in its shaping activity.

Therefore, the phenomenological analysis highlights the points which have to be improved in order to achieve the goals of having computers merged with our everyday world.

Moreover, it helps to understand the knock-on effects of this technology in our community by analysing the kind of relation established by it.

However, this analysis of augmented reality needs a preliminary general anal-ysis of technology related to perception. In order to highlight the important effects augmented reality will have on ourselves and on our world, we need to focus our attention on the way technology interacts with the subject and the world.

Technologies are not neutral indeed. Their effects touch what we are and the world where we live by shaping them and by introducing new elements and new “aspects”.

They cannot be seen as something inert used by the subject in a “clean” and one-way action. It is an interaction and everything enmeshed in such a relation changes accordingly.

We need to understand how the subject,technology and the world interact between them. We need to focus our attention on the perceiving body of the subject and the everyday world of the subject in order to highlight how tech-nology is deeply intertwined with them.

1.1 Aim and Scope

Augmented reality will be a technology pervasively used. Therefore it will have deep knock-on effects on our society.

The aim of this thesis is to analyse augmented reality in its relations with the world and the subject.

There are two main questions to be answered. Will augmented reality shape our world and our living body? If yes, how will it mould our surroundings and ourselves?

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In order to provide such answers we need to focus our attention firstly on how technologies in general mould our world and the subject and only in the second step can we move to analyse augmented reality.

Therefore, the thesis will be structured in two main parts which identify the two different steps of our analysis.

1. The first part will focus on the relation between the subject, technol-ogy and our world in a wide sense, without taking into consideration the augmented reality as a specific technology. This part will be internally subdivided into two chapters:

(a) One chapter1will be dedicated to the preliminary analysis of the way the technology can shape our world and our perceptual capabilities by introducing the main keywords which we will use in the following chapters. In particular, we will study the constitution of the optimum through technology and we will introduce the embodiment relations in post-phenomenology.

(b) A second chapter2 will be devoted to the analysis of the constitution of the everyday world and our living body3 _{following a Husserlian}

analysis and highlighting the relations to technology in this process. 2. The second part will be focussed on augmented reality. This is a tech-nology which is going to become pervasively used and so it is important to have an idea of its possible knock-on effects. Thanks to the previous part, we can think of a technology which moulds what we consider natural and basic. Therefore, we can take into consideration this new technology as something which will produce changes in our world. This part will be subdivided into three chapters:

(a) The first chapter4 _{introduces augmented reality and understands}

what kinds of objects can be created by such technology. Here we will demonstrate that the augmented objects are not fictional ob-jects, such as in the case of virtual reality, and we will introduce the concept of “digital materiality” to identify the kind of matter which they are composed of.

(b) The second chapter5 _{of this part will be devoted to understanding}

why the augmented reality is a new technology and to focus attention on the way it should be used in order to have a complete different technology from the previous already existing ones. Here we will study its relations with Ubiquitous computing, its differences and their different potentialities.

(c) The third and last chapter of this work6_{will be focussed on how this}

technology will yield deep modifications in our everyday world and in our living body. We will focus attention on AR glasses because

1_{See chapter number 2.} 2_{chapter number 3.}

3_{We will use the concept of the everyday world [Lebenswelt] and living body [Leib].} 4_{See chapter 4.}

5_{See chapter 5.} 6_{See chapter 6.}

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they are the most promising device for the augmented reality and we will analyse how they relate to the subject and the world using the previous analyses as a background.

Therefore, we can take the first part as a theoretical framework where we will demonstrate how technology cannot be something added to a more primal core. The first two chapters allow us to take technologies as something active which have the potentiality to mould the world and ourselves.

Thanks to such a preliminary analysis, we can introduce the augmented reality not as a mere “inert” technology, but as something quite active.

Technology “bites back”.

In order to probe how deep it sinks its teeth into our flesh we need both parts: the first for understanding how “playing” with snakes bears consequences and the second for studying the way the venom spreads in our veins.

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Part I

Phenomenology and

technology

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Chapter 2

Technology and the

perceptual world

2.1 The world’s constitution through

technol-ogy

2.1.1 Introduction

This chapter focusses on technology and on how it shapes our surrounding world. The questions which we are going to answer are: Is it really adding something to our world? If yes, how does it mould our living world?

Technology is always considered something which helps the subject to achieve a different perception. Technology allows us to perceive the world around us in a very different way and, moreover, it tends to present objects that are not perceivable by the naked subject. However, it is not so clear what changes with such perception. It is not so clear how to consider the changes in our world produced by technology.

We are going to tackle the problem using a phenomenological approach fo-cussing our attention on the perceptual level.

The chapter is structured in two main parts:

1. The first part focusses on the optimum of the object. Here we will take into consideration how the object is constituted through changes in the environment and in the subject.

2. The second focusses on which kind of technology can actually modify our world. Here we will take into account embodiment relations in post-phenomenology.1

2.1.2 Optimum of the object

In order to study how technologies shape the perceived object we can study the perception of an object in Husserl’s phenomenology.

1_{In order to have an introduction to post-phenomenology see Selinger 2006b or Verbeek}

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Every object gives itself in a particular way of manifestation. Its way of manifestation changes in space and time even if the object remains the same object perceived before.2

The notebook lying on the table in front of us can be open, closed, it can be on the table or on the desktop of our office. However, the computer is still the same computer in each moment and in each different spatial position.

This statement identifies the necessary relation between the actual percep-tion of the object and the wider pool of its possible perceppercep-tion of it. The object is always something more than what is seen, it is something more than its ac-tual manifest aspects.3 Even if the object presents itself with a particular face according to the spatial position of the subject and their “time position”, the object is something more.4

Moreover, following the Husserlian analysis, every object has an “optimum” of manifestation that is the “true” content of the object.

Immer gibt eine Akkomodation ein Bestes, und das ist das ‘Wahre’5

Therefore, that is the most interesting part for his analysis, the object is always perceived according to its “optimum”. The “optimum” is the true content of it and, therefore, the object always brings it in itself.

Normal experience establishes for itself an optimum, a kind of standard of variation: the cylinder appears like this form here and like that from there because these appearances are ordered variations of how it appears optimally, that is, from the best angle and in the

best lightning conditions. Thus there is a kind of norm in perception

itself6

The presence of the “optimum” identifies the existence of a normative stan-dard7 for the perception of the object.

Es gibt die eine normal konstituierte Welt als die wahre Welt, als „Norm” der Wahrheit und es gibt mannigfaltige Scheine, Abwe-ichungen der Gegebenheitsweise, die durch Erfahrung der psychoph-ysischen Konditionalität ihre „Erklärung” finden.8

The object is perceived in an optimal way only if it is perceived with the “richness” we have in the optimum.

2_{This is the nature of the object as intentional object. “Instead, the tower is a unified}

“intentional object” that remains the same despite being presented through the greatest variety of different perceptions.” (Harman 2011). See also Sokolowski 1974.

3_{This is not related only to the concept of horizons. See section 6.2 at page 129.}

4_{For example, Harman explains this fact by making a parallelism with the writer Lovecraft.}

The monsters of Lovecraft are objects in the same world of humans and, at the same time, they are completely unreachable by human beings. Lovecraft opens abysses in the “ordinary” life by introducing the infinitness in common objects. In the same way the objects, in Husserl, are always something more than what we can perceive, they are infinite in almost the same sense of Lovecraft’s abysses. See Harman 2008.

5_{Husserl 1952, p. 311.} 6_{Crowell 2013, p.142.}

7_{For a study on Husserl and Foucault see Gyllenhammer 2009 and Carr 1987.} 8_{Husserl 1952, pp.73-74.}

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Identifying with P (O) what is perceived of the object O, with OOptimum_the

content of the optimum of the object O and with Richness(x) the richness of details of x we have:

P (O) = OOptimum ⇐⇒ Richness(P (O)) = Richness(OOptimum) Otherwise the perception of the object is not an optimal perception. That means it has not the complete richness of “details” we would have perceiving its optimum.

P (O) < OOptimum ⇐⇒ Richness(P (O)) < Richness(OOptimum₎

It is possible to have different kinds of modifications of the object which induces a non-optimal perception of it.

Therefore, the optimum is normative because it provides what has to be considered the “normal” perception of the object.

The optimum, according to Husserl, is created in relation to the richness of the object. The more details we can perceive of the object, the better it is.9

Richness(P (O)) > Richness(O_oldOptimum) ⇓

P (O) OOptimum new

The optimum is based on the richest possible perception of the object. To say that we “prefer” such a situation means that “normally” we tend toward the “maximum” of richness or maximum of focus in which the object is both sharp and differentiated, that we are aesthetically uncomfortable or unbalanced when the light or distance is excessive or deficient.10

Thus we cannot consider the constitution of such optimum as something related to a skeptical point of view because this norm is not uprooted from the world where the subject lives.

But he does not mean to imply that normality for the members of a community is merely a matter of what the majority of them happen to be like, how their perceptual systems presently function. [. . . ] Husserl’s understanding of the standards of normality is not relativistic.11

The “norm” represented by the optimum can change if a new way to perceive the object that makes it richer emerges.

The fact that the optimum, which is the norm, is constituted following the richness of the perception can be problematic.

9_{“im Schatten sieht man nicht so viele Unterschiede; das Hellere, Belichtete gilt als das}

Bessere und die Norm” (my emphasis) (Husserl 1910, 1915; 1916, 1917, 206b).

10_{See Steinbock 1995, p.139; Fricke 2012, p.207.} 11_{Fricke 2012, pp.206-207.}

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Richer= Better?

Following the Husserlian analysis a colourblind community should change its optimum and its norm when they meet a community that is not colourblind.

Für den Farbenblinden ist der normal Farben Sehende die Norm [. . . ]12

The norms are shaped according to the richness of details the subject can perceive. Therefore, a community without the capability to perceive colours has to change its colourless optimum in the case it meets a subject or a community who can achieve such details because it identifies its “old colourless” optimum as poorer than the colourful one.

To say that the optimum of the colour-blind community has to be replaced by the optimum full of colour of another community is comparable to say that the optimum of a perception “without colours” has to be substituted to the optimum of a perception “with colours”. That means it is comparable to say that the optimum of black and white photography has to be substituted by the optimum “full of colours” of the more classic photography.

We need not to be expert photographers to understand that black and white photography is not worse than colour photography, but only different. The absence of colours is used to highlight some particulars and to focus the attention of the perceiving subject on some details or some lines that would be hidden by colours. Colours can distract the subject and they cannot allow us to focus the attention on some aspects the photographer wants to highlight. Colours can blind the subject.

The optimum, in this case, cannot be considered as founded on the richness of a colourful picture because it hides some aspects of the picture and does not allow the focalisation of the attention on such details.

Richness(B&W ) ≮ Richness(Colour) O_B&WOptimum≮ OColourOptimum

Even if the perception in black and white is a perception without colours, it enables the perception of other details which are hidden by colours.

The optimal perception of an object, and therefore the optimum of the ob-ject, is not related to the richness of details as if there were a perception with more details than others in an absolute sense, but it is possible to have multiple different optima founded on the different details highlighted by different kind of perceptions.13

Therefore, taking into consideration the Husserlian case of a colour-blind community14_{, the community sees the world without perceiving the colour of}

the surrounding objects. However, we cannot identify this lack of colours as a

12_{Husserl 1973d, p.132.}

13_{This is the necessary relation between optima and praxes we are going to highlight in the}

next pages. See at page 11.

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complete deficit. Their optimum is not “worse” than the colourful one in an absolute sense because even if it has not a particular kind of detail it enables the community to perceive different aspects of the world. Putting it simply: the colourless perception is not “worse”, but only “different”.

This statement implies that the single object cannot have an unique optimum according to the richness because the richness is not univocal. We can have a picture in black and white that is not worse than the one in colour because it highlights different details. Thus we have two different optimum depending on which details we are interested in.

Every optimum allows the subject to perceive the world in a different way highlighting different aspects of it. Therefore, different praxes15_{could need the}

highlighting of different aspects of the object, which means different praxes can need different optimum.16

The optimum may not be “better” in an absolute sense, that is for every praxes, but it can be better in relation to a specific praxis.17

Identifying with Colour and B&W the two kinds of photography we can take and with P raxisxthe praxis related to the x technique we have:

P raxisColour needs OColour

⇓

P (O)P raxisColour  O

Optimum Colour

and vice versa:

P raxisB&W needs OB&W

⇓

P (O)P raxisB&W  O

Optimum B&W

Another point that has to be mentioned is that the constitution of the opti-mum is not something “active” made by the subject. It is related to passivity.18 The subject does not decide if the object is given in its optimal perception or not. The object provides by itself its optimum. The subject, perceiving the object, perceives it always in relation to its optimal perception.19

P (O) ⇒ P (O) P (OOptimum₎

⇓ always

Richness(P (O)) ≷ Richness(OOptimum₎

15_{We use the term “praxis” in the widest sense. Therefore we have a “praxis” in the case}

of an activity derived by social costumes or in the case of a practical action in opposition to theoretical approach

16_{See Steinbock 1995, pp.140-143.}

17_{The praxes related to some aspects require the optimum related to such aspects because it}

is the best way to achieve such aspects of the object. That is also highlighted by K. Mulligan. “The optimal or normal perspective on a thing varies with the interests of the subject. But given such interests, there is an internal relation between the appearances of the thing which is their different distances from the relevant optimal appearance” (Mulligan 1995, p.204).

18_{See Husserl 1966 and, in order to have a wide panorama on such a concept, Biceaga 2010.} 19_{“I feel things poorly” (Steinbock 1995, p.144).}

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However, in our analysis, it is not important to study the reason why the optimum of the object is created according to the richness of the object. It is important only to identify the possible modification of such optimum and to identify it not as something “static” immutable through time and cultures.

The optimum can change and, with it, the norm of the community.

The optimum can change thanks to many modifications in the environment or in the subject.

2.1.2.1 Environment

The first case we can take into account is the modification of the environment where the object is immersed. The object is always related to the environ-ment where it is and its perception depends on the characteristics of such an environment.

The perception of an object changes according to the modification in the surrounding environment.

The classic case where the object changes its “apparent” content is the mod-ification of the surrounding illumination.

The colour displayed by the object is light dependant. The object has its “true” colour, that is identified by its optimum, but it shows itself with a dif-ferent colour depending on the illuminating light.

If we are in a dark room of a vintage analogue photographer while we are preparing to print on paper the image they have on the impressed film, the object “printing paper” will appear red because the only illuminating light in this environment is a red bulb.

However, the printing paper is not red. It relates to other possible percep-tions and, in this case, to the other “normal” environmental condipercep-tions of a sunny day.

The example of the daylight is made by Husserl himself.

Dabei stellen sich gewisse Bedingungen als die „normalen” her-aus: das Sehen bei Sonnenlicht und hellem Himmel, ohne Einwirkung anderer die Erscheinungsfarbe bestimmender Körper. Das „Opti-mum”, das hierbei erreicht wird, gilt als die Farbe selbst, im Gegen-satz etwa zum Abendrot, das alle Eigenfarbe „überstrahlt”. Alle

anderen Eigenschaftsfarben sind „Aussehen von”, „Erscheinungen

von” dieser ausgezeichneten Erscheinungsfarbe (die „Erscheinung” nur in einem anderen Sinne heißt, nämlich mit Rücksicht auf die noch zu besprechende höhere Stufe des physikalischen Dinges).20

The object “printing paper” is seen as red. However, it has an optimum which makes it a white piece of paper instead of a red one.21 It is as if the object suggests to the subject to turn on the light in order to have its optimal perception.

20_{Husserl 1952, p.59. See also “Das Tageslicht, der helle Tag läßt die Dingmerkmale am}

reischsten und differenziertesten hervortreten, in ihm betätige ich mich daher mit Vorliebe” (Husserl 1910, 1915; 1916, 1917, 160b).

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Figure 2.1 – The white printing paper is seen as “red” under the red light of a dark room. However, the subject is in front of a white paper according to its optimum, that means according to an optimal illumination of a sunny day (this image is taken and modified from the website http://commons.wikimedia. org/wiki/File:Dark_room.jpg).

P (O) = (Red) ; OOptimum_{= (W hite)}

⇓

P (O) 6= OOptimum

Moreover, this example highlights another important relation that is needed to have an optimum: the optimum is always perceived according to “optimal environmental conditions”. The perception of an object is not dependant on other perceptions of it in general, but it is related to other perceptions in other environmental conditions. Therefore, in order to have the chance to have an optimal perception we need to have optimal environmental conditions.

Identifying with ECx _{the environmental conditions related x, we have:}

ECP (O)= (Red Light) ; ECOOptimum = (Daylight)

⇓

ECP (O)_{6= EC}OOptimum

⇓

P (O) 6= OOptimum

We cannot achieve an optimal perception of the object if we are not in the conditions for such perception. It is impossible to reach the optimum of the white paper in a dark room without an illuminating light source that mimics the “optimal environmental conditions” of a sunny day.

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Therefore, the object relates itself to these normal conditions that allow an optimal perception of the object. The colour of the object we see is the “true” colour of the object, is the optimum of the object, only in the optimal environment which provides normal conditions.

By modifying the condition of the environment we have the possibility to modify the optimum of the object. The perception of the object is related to the environment where it is and, therefore, a variation of this latter element produces the variation of the aspects shown by the object.

ECold ECnew

⇓

P (O)old P (O)new

A different environmental condition implies a different perception and there-fore it is possible to have the modification of the optimum of the object.

ECold⇒ OOptimum_old

ECold ECnew ⇒ OOptimum_old Onewoptimum

Where

OOptimum_old 6= Onewoptimum

Maybe we cannot say that the new optimum is “better” than the old one, but we can say that it is different because it enables us to highlight different aspects of the object at least. This is enough for our purpose because we need only to make manifest the possible modification of the optimum of the object through the modification of the environment where the subject is immersed.22

The optimum can change according to the environmental conditions because these conditions allow a different perception of the object and they make it possible to perceive different details of it.

To have a concrete example, we can take into account the ultraviolet light.23 It is possible to use a UV illumination in order to highlight different aspects of the surrounding world.

This kind of new “environmental” condition alters the colours and makes the perception of the classical colours impossible. However, even if it is not “better” in an absolute sense because it does not allow the subject to have a colourful perception, it allows the subject to perceive different details such as the damaged part of a canvas24, or to highlight scorpions in the desert.25 These kinds of details would be unreachable by the subject without such modifications in the environmental conditions.

22_{As we have said above at page 12. For us it is not important to identify this modification}

of the optimum as a betterment of the previous optimum, we need only the possibility of a modification in this optimum.

23_{That are also called black light or wood’s lights.}

24_{UV photography is used to highlight the part of a canvas which has to be restored.} 25_{UV light highlights the colour of such animals and so using this particular illumination it}

becomes possible to identify scorpions in the dark because they glow. See, for example, Gaffin et al. 2012.

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ECDaylight ECU V

⇓

O_DaylightOptimum_OOptimum_{U V}

The modification of the environmental conditions can yield the modification of the optimum because it allows the subject to better26 _{perceive the object by}

highlighting some aspects of it.

P raxisAspectsneeds OAspects

Richness(EC1O Optimum Aspects ) < Richness(EC2O Optimum Aspects ) ⇓

P (O)P raxisAspects EC2O

Optimum Aspects

2.1.2.2 Subject

The modification of the environment is only one of the possible modifications that can yield a corresponding modification of the perception and the optimum. Another case we have to take into consideration is the modification of the subject.

It is possible to have many kinds of variation in the subject that can yield a modification in the perception of an object.

For example, the subject can perceive more details of the object by getting closer to the subject. Thanks to this simple action, the subject achieves a better perception of the object because they achieve more details of it.

In this way the optimum of the object is enhanced because the subject can “see” more details of it.27

Richness(P (O)Close) Richness(P (O)Distant)

The optimum of the object is modified by such perception because the object becomes constituted by new details perceivable by getting closer to the object.

OOptimum_Distant _OOptimum_Close

Also this kind of modification is not related to the “simple” more richness of details of the closer perception without taking into consideration the praxes related to it. For example, if the subject wants to see the object in its wholeness they need a certain distance in order to get the entire image of it, but if they are interested in some details, the subject needs to get very close to the object losing the perception of the entire object.

However, we can consider the modification of the subject in its spatial posi-tion as an acposi-tion that modifies the constituposi-tion of the object, at least potentially. The object is enriched by new details, even if the subject loses the perception of the entire object when they get closer to it.

26_{We can use the term “better” because it can be related to the praxes of the subject}

without considering a better absolute richness of the perception. A praxis is related to some details and a modification in the optimum which enhances such details helps the action.

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Another possibility to enhance the perception of an object is to use a techno-logical device. The subject, instead of moving themselves in order to get closer to the object, can simply wear a pair of glasses.28

Figure 2.2 – Classic optical glasses allow to perceive more details of the object. The object becomes sharper and “richer”.

Husserl takes into account the possibility of wearing a pair of coloured glasses that modifies our perception of the color of the thing. Even if it is not the same example because the subject does not perceive more details, but they perceive the object with different colours, it is important because they take into account the possibility to modify the subject’s perception with a device.

Und schließlich, lege ich eine farbige Brille vor mein Auge, so sieht alles farbig geändert aus.29

The subject, thanks to the technology, can perceive details that could be invisible by them in their spatial position. Or, more radically, the subject can implant a technology in their body making the usage of such technology inevitable.30 _{For example, the subject can introduce in their eyes the lenses}

thanks to a surgical operation instead of wearing them.31

The perception of an object is changed by technology even if it is a modifi-cation yielded by something “in”32 _{the subject and not something external to}

them such as the environmental conditions.

28_{See figure 2.2.} 29_{Husserl 1952, p.60.}

30_{See for example the cyborg culture or the post-humanism. See Haraway 1991; Hayles}

1999; Hayles 1993; Winner 2004.

31_{See for example figure 2.3.}

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Figure 2.3 – Thanks to the insertion of an internal lens it is possible to treat cataract (this image is taken and modified from the website http://www.greatlakeseye.com/ s2Cataract.htm).

The object becomes “sharper” and more “defined”.

The optimum of the object is moulded in the same way as before. The object in the distance is perceived with more details thanks to the glasses worn by the subject. The optimum of the object is modified because it becomes “richer” and the old perception of an object in the distance is perceived as “blurred” because the subject cannot achieve such richness.

Richness(P (O)N aked) < Richness(P (O)T echnology)

OOptimum_{N aked} _OOptimum_{T echnology}

P (O)O

Optimum T echnology

N aked = blurred

Therefore, the constitution of the normality of the perception of an object, and the normality of the perceptual capabilities of the subject are founded on the optimum of the object. That means the normality of perception is founded not only on the “original” perceptual capabilities of the subject but even on the modifiers of such perceptual capabilities. Environmental conditions and the modifications of the subject are important factors of the constitution of the optimum, thanks to technology, and thus they are important even for the constitution of the normality of the perception.

Obviously, we could take into consideration the presence of the technologies in the environment. In this case we would have technologies that are “external” to the subject but still active because they act modifying the environmental conditions.

the living body of the subject even if they are not internal as the lenses introduced by surgical operation. See at page 23.

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ECN aked ECT echnology

Where, with respect to some praxes33_{, we have}

P (O)ECN aked P raxis < P (O) ECT echnology P raxis ⇓ ECN aked < ECT echnology

However, in this work, we refer only to technology that interacts with the subject in a more strict way. Technologies acting in the environment will be left apart.34

2.2 Which technology?

The relation between optimum and technology implies that our living world is shaped by technology as well. Technology, by modifying the objects around us, modifies the world where we live.

We are surrounded by technologies that interact with us providing informa-tion, knowledge and perceptions of different aspects of the object or even of entirely different objects.

Technology allows us to enlarge the world where we live, but it is not clear in which way such an enlargement is produced. It is not clear if technology yields a modification related to our perceptual world or a “mere” amplification of our knowledge.35

The status of what is achieved through technology is not clear. It is not clear if technologies provide perceptual objects or “only” information about the surrounding world.

Therefore, the three main questions related to such problems are: 1. Are all technologies shaping our perceptual world?

2. Are there some differences between technologies that can be put into dif-ferent groups?

3. Are glasses, radio-telescope and particle accelerator the same?

2.2.1 Criterion based on the content

In order to answer these questions our first attempt is going to be to make a dis-tinction between what is perceivable by our naked body and what is “visible”36

thanks to devices.

33_{See at page 11.}

34_{That means we are not going to take into consideration two kinds of relations among the}

subject, technology and world identified by Ihde: alterity and background relations. See Ihde 2009b, pp.43-44; Ihde 1995, p.108; Ihde 2004, pp.89-97.

35_{That means it is something related to scientific theories only.}

36_{We are using the term “visible” as perceivable and therefore, it has not to be limited to}

the visual field. The use of “sight” has to be preferred because we will deal with it more than the other senses, i. e. we will study perception through glasses (see chapter 6 at page 127)

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Thanks to this distinction we can consider part of our world only what is perceivable by our naked body without the help of any technology.

There are many technologies which help the subject to perceive something that is not perceivable by the naked subject. These kinds of technologies would be excluded because they would introduce elements not “reachable” by the naked body of the subject.

Technology is considered something strictly derived from the naked percep-tion. In this conception, it is conceived only as a magnification of our naked perception and nothing more. Therefore, every technology which tries to intro-duce new elements in our perceptual fields is excluded.

For example, classic glasses allow us to perceive the object with more de-tails without getting closer to it. These dede-tails are “real” perceptual elements because the subject can achieve such a perception even with their naked eye by getting closer to the object. Therefore, these details are visible by the naked eye and they are “real” perceptual elements even if they are perceived through a technology.

Thus glasses yield a modification of the perceptual optimum of the object because they allow the perception of such details.

AspectsT echnology= AspectsN aked ⇒ O

Optimum N aked O

Optimum T echnology

⇓

AspectsGlasses= AspectsN aked ⇒ O_{N aked}Optimum OOptimum_Glasses

In the same way the optical telescope yields the modification of the optimum of the object because it introduces more details that are commonly perceivable by an hypothetical subject close to the celestial body. The mountains on the Moon become part of our perceiving world because it would be possible to have such perception if we were on the Moon’s surface.37

The mountains on the Moon become part of the perceiving world for their “common” perceptibility.

Following this point of view, a technology which produces objects or aspects of the object that are not perceivable by the naked body cannot be considered a technology that modifies our perceptual world.

For example, particle accelerators do not introduce any other elements in our world because what they analyse is something too small and strange for a naked perception.38 Electrons do not exist in our perceptual world because they simply are not reachable by naked perception. They are too small and too “weird”.

This kind of technology can provide knowledge but not a perceptual aspect of the object. The fact that an object is composed of electrons or other sub-atomic particles does not mean we perceive the object as a bundle of particles.

37_{Neil Armstrong in 1969 landed on the Moon and he perceived the same mountains we can}

perceive through the telescope’s lenses.

38_{It is not only too small to be perceivable by naked eye, but it is also something that has}

not the same characteristics of a common object. Schrödinger’s cat (Schrödinger 1935) is a classical example of the translation of the quantum physics’ laws to a more common object: a cat. Therefore we have an object that is something perceivable by the naked body but it has characteristics that are not tied to the common perception.

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Technology, in this conception, is conceived as a magnification of our pre-existing capabilities.

P (O)N aked< P (O)T echnology

What is visible by glasses is visible also by the naked eye, even if naked perception is weaker. This conception makes the distinction between what is part of our perceivable world and what is not.

An aspect of the object is part of our world only if it is perceivable by the naked body of the subject.

OAspects∈ W orldP erceptual _{⇐⇒ ∃P (O}Aspects₎ N aked

And an entire object is part of our world only if it is perceivable by the naked body of the subject.

O ∈ W orldP erceptual ⇐⇒ ∃P (O)N aked

Unfortunately, such a conception has to be abandoned because it does not take into account that technology implies reductions and other modifications apart from magnifications.

The perception through technology is not a naked perception “enhanced” by the technological device in an absolute sense. Technology does not introduce new details maintaining the others unmodified.

For example, glasses, sharpening the object, introduce chromatic aberrations and distortions. Optical telescope introduce a greater magnification and, with that, greater chromatic aberrations and more distortions. Technology always produces reductions of the perception as well as magnifications.

P (O)T echnology = P (O)N aked+ Aspects

M agnif ication

T echnology + Aspects

Reduction T echnology

Therefore the optimum cannot be an absolute improvement of the optimum constituted by naked perception because it has reductions as well as magnifica-tions.

O_{T echnology}Optimum ≯ OOptimumN aked

The optimum, as we have seen before39_{, cannot be taken as something}

abso-lute that is improved by a different perception that allows us to catch different aspects of the object40_{. It depends on what we have to do with such optimum.}

It depends on the praxes we are interested in.

Therefore, technology cannot be a magnification of pre-existing perceptual capabilities. It is not something that enhances our perception of the world in an absolute sense, but it allows us to “reach” different aspects in the world.

The telescope or glasses are not a magnified naked eye. It allows the subject to appreciate different aspects of the world.

Therefore, technology can introduce aspects completely hidden and pre-cluded to the naked body of the subject because it is no more a magnification of what can be perceived by the naked body. The objects in the world becomes

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embedded with aspects that are not visible by the naked eye, but only through technologies because their optimum is technologically founded.

The object itself starts to suggest the usage of a certain kind of technology in order to have a better perception of it.41 _{It suggests that the subject should}

wear glasses or use a telescope in order to achieve a better perception of it. This is a direct effect of the passivity of the optimum. The optimum, as we have seen above42_{, is given in a passive way to the subject. Thus the subject,}

who is directed to the object according to a certain praxis, gets the object in its relation to the particular optimum that fits their needs.

P raxisAspectsn

⇓

P (O) OOptimumAspectsn

If the technology “enhances” the perception of such aspects we have the perception of the object in relation to the optimum that is technologically con-stituted.

Richness(T echnologyOAspectsOptimumn) > Richness(N akedO

Optimum Aspectsn)

⇓

N akedOOptimumAspectsn T echnologyO

Optimum Aspectsn

This fact implies that the subject can live in a world where the object is constituted by some aspects that are not “reachable” by the naked body and so it introduces the possibility to have a world strictly related to technology. The object starts to suggest the usage of a particular technology in order to achieve a better perception of it.

We can have objects with some aspects founded on technology, but we can also have objects completely constituted by aspects perceivable through tech-nology only.

A blurred object could be seen in a better way using a pair of glasses, but, following our analysis, we can have an object composed of aspects visible through technology only.

For example, we can have objects that could be seen only on infrared light. In order to achieve the perception of such object we need to use a sensor sensitive to light with a wave length longer than 740nm.43

Only thanks to such kind of device the object becomes visible to the sub-ject and it cannot be excluded by our perceptual world only because it is not perceivable by the naked eye.

The criterion on how to classify the “product” of such technologies cannot be found in the content of the object. We cannot use the criterion based on the content of the object: if the content is perceivable by the naked body or not.

41_{Obviously always related to some praxis. The better has to be identified always in relation}

to a praxis. It is the praxis that gives the basis to have a better perception because it is the praxis that needs the emphasis of some aspects in the world.

42_{See above at page 11.}

43_{See, for example, for far-infrared Ring and Ammer 2012; Berz and Sauer 2007;}

Hilde-brandt, Raschner, and Ammer 2010 or in a more “artistic” way for photography, see, for example, for near-infrared Harnischmacher 2012; Farace 2006.

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2.2.2 Criterion based on the way the technology works

with the perceiving subject

The criterion we can use is not focussed on the content of what is perceived through the technology, but it focusses on how the technology relates to the perceiving subject.

We can take into consideration the relations among the subject, technology and the world in post-phenomenology44_{because they tackle the problem on how}

the technology works with the subject.

As we have said above45_{, we are going to analyse “only” the technologies that}

are related to the subject in a strict way such as glasses and not the technology that are disposed in our environment that are outside of our perception even if they constitute our world as well.46

Technology can be a body enlargement in mainly two different ways: it can be in an embodiment relation with the subject or it can be in an hermeneutic relation with them.

People can incorporate technologies, as when wearing a pair of glasses which one does not look at but looks through. Other technolo-gies we have to read, in the way that a thermometer gives informa-tion on temperature or an ultrasound machine gives a representainforma-tion of an unborn child” 47

In Ihde’s opinion, there are two additional types of relations: the alterity and the background relations. However, these relations are not focussed on the perception of the subject through technology, but, in the case of the alterity, they are related to the way the subject perceives the technology relation, and, in the case of the background relations, the way the environment is filled with technology that are acting in a hidden way and which are shaping the world the subject is living in.48

We can take into consideration the first one and we can focus on the elements which make it different from the hermeneutic one. Thanks to such analysis we will be able to understand how to consider the “product” of the technology and to understand if this product is enhancing our perceptual world or not.

Therefore, we will have the answers to the questions previously posed49 on which technology modifies our perceptual world.

2.2.2.1 Embodiment relations

This kind of relation includes any possible bodily enlargements, as it is gen-erally understood. Every tool, which allows us to perceive an object without becoming a perceived object itself, is considered a body’s enlargements. The tool withdraws, allowing the perception to flow through it and to point at the

44_{We identify the post-phenomenological movement as the “technological turn”}

phenomenol-ogy had with Ihde. It studies technolphenomenol-ogy and how it interacts with the subject and the world from a phenomenological point of view.

46_{For example we are going to analyse glasses and not the fridge in our house, even if both}

of them have an important effect on our life.

47_{Verbeek 2009.} 48_{See at page 18.} 49_{See at page 18.}

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“eternal” object without any interposing hindrance which would produce the stagnation of this flow in the technological device itself.

The subject can live in “symbiosis” with the technological instrument and they are directed to the world as if there were not any mediation

My glasses become part of the way I ordinarily experience my surroundings; they “withdraw” and are barely noticed, if at all. I have then actively embodied the technics of vision. Technics is the

symbiosis [my emphasis added] of artifact and user within a human

action50

Technology can be embodied into the subject. Even if the technology does not become an integral part of the body as a piece of flesh, it can be considered a part of it for two reasons:

1. The technology “withdraws” and allows the subject to directly perceive the “external” object without being perceived.

2. Technology allows the subject to perceive something very close to the normal perception even if with modifications.

These two aspects are the two transparencies the technology must have in order to be in embodiment relation with the subject and to be in symbiosis with them.

Otherwise the technology is not in an embodiment relation but it is in a hermeneutic relation.51

2.2.2.2 Transparency of directionality

Technology has to be transparent because it has to allow a direct perception of the object in front of the subject. The subject has to be focussed on the object as if they were naked. They have not to “think” or “be distracted” by the medium they are using. The technology “withdraws” in the sense it becomes a part of the pole where the intentional act is based.52

From being something perceived it becomes something with which the in-tention and the perception is generated. Not only is the perception of an object founded on the possible technology the subject can use, but even the motivations and volitions are modified by such use.53

50_{Ihde 1990, p.73.}

51_{We are excluding the alterity relations and the background relations from our analysis as}

we have said before. See at page 18.

52_{“My glasses become part of the way I ordinary experience my surroundings” (Ihde 1990,}

p.73). See also Watson 2007 on the relations between Ihde and Mereau-Ponty.

53_{The motivations of the subject changes according to the technologies used. Therefore, the}

use of a technology instead of another can be preferred because it provides different changes in the subject. That is what Verbeek, quoting Baudet (see Baudet 1986), suggests . The use of a certain kind of pen yield a modification in the subject at a deeper level. The use of the “old” pen instead of the “new” ball-pen is pedagogical, the device embedded a “general social discipline”(Verbeek 2005, p.115). In our case, the use of LA_{TEX does not produce the same}

result of a ball-point pen or another word editor, the structure of the document is modified by the device we use. Ihde, for example identifies the technology as non-neutral because the pen tends to write “belles lettres” while the typewriter inclines the subject to a journalistic prose. See Ihde 1979; Restivo 1981. Maybe these examples fall within psychology and not within phenomenology. However, to provide simple cases is useful to highlight these effects in order to understand in a better way how technology interacts with the subject and the perceived object.

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Ein Werkzeug ist eine Erweiterung des Leibes, nämlich, wenn es „im Gebrauch” ist. Es ist sowohl eine Erweiterung des empfindenden Leibes als auch des Liebes als Willensorgane54

The subject looks “through” the technology and not “at” it.55

(Subject) → Object ⇓

(Subject − T echnology) → Object

Figure 2.4 – The subject’s intentionality flows through the lenses directly toward the object. (Subject − T echnology) →

Object

The subject perceives the object with the mediation of the technology but without noticing such “action”. In the case the subject looks at the technology instead of through it we have the hermeneutic relations56:

Subject → (T echnology − Object)

The object is perceived as if it were no technological medium at all, even if the effect of such technological mediation can be seen in the richness of the object.

If the technology has such transparency it allows a perception of the object as something in the world. It yields a perception of an object in our world as any other common object. The aspects of the object are aspects in the object because the subject is directed to it in the same way as a naked perception.

Moreover, if we have an object founded on aspects perceivable through tech-nology only, we have an entire object that is part of our world as well as the common objects perceivable by naked perception.

For example, we have such transparency with a pair of glasses. The subject, wearing them, does not perceive the lenses but the external object embedded with new details.

54_{Husserl 1971, p.7.}

55_{See figure 2.4 at page 24. See also Nagataki and Hirose 2011.} 56_{See Ihde 1990.}

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In the case of an object visible only with an infrared sensor57_{, the “infrared”}

object becomes something of our world because it is perceived in our world and not something represented on a monitor if we have a technology with such transparency.

SubjectN aked → W orldN aked

SubjectT echnology → W orldT echnology

⇓

SubjectT echnology+ SubjectN aked → W orldN aked+ W orldT echnology

We do not have such transparency in the case of a radio-telescope.58 _This

technology creates a “duplicate” of the “external” object.59 _{The celestial body}

is represented in the monitor in false colours. The original object is duplicated and recreated in the medium that monopolises the attention of the subject. The subject focusses their attention on the duplicate and not on the originary object up in the sky. They do not act and perceive the external world any more, but they are immersed60in the monitor looking at the representation of such world. Optical glasses are quite transparent in this sense. However, we can think of a more transparent device such as a neural stimulating device.61 In this case the device completely disappears in the body of the subject, it allows them to have a “pure” direct perception of the object without introducing interposing elements between the subject and the external object.

2.2.2.3 Noematic transparency

The second transparency is related to the content of the object.

Technology, as we have seen62_{, enhances subject’s the perception. It modifies}

the content of the object by introducing new aspects and details. Moreover, technology is used for such a reason and no one would use a technology that does not imply any modification at all.

A completely transparent technology would be absolutely useless.

No one would use a pair of glasses that does not yield any modification in our perception or in our praxes because if there is no modification, there is no need for such technology.63

OAspects_{N aked} 6= OAspects_{T echnology}

Obviously, the content has to be modified by the technology, however this modification can vary a lot. In order to have the noematic transparency, we

57_{See above at page 21.}

58_{Radio-telescopes are what Ihde called imaging technology, see Ihde 2009a.} 59_{That is also a representation of the “external” object.}

60_{We will see how this immersion will be important for augmented reality (see section 4.5.2}

at page 95).

61_{See, for example, the brain computer interface evolution. See Guger, Allison, and Edlinger}

2013; Poli, Salvaris, and Cinel 2011.

62_{See at page 2.1.2.2 at page 16.}

63_{Even a transparent technology designed to be colourless and without any correction of the}

sight yields a modification because they protect the naked eye of the subject. For example, they could be used as protection in a case of workers who need protection for their eyes.

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need to have a modification that is comparable to the classical content of the object.

The object has to remain a perceptual object that entails the specific action the subject would have in the case of a common object perceivable by the naked body. This kind of transparency tackles the problem of how we face the different kinds of objects.

A perceptual object could vary. However, there is a deep difference between a common object that needs only perception to be perceived and an object that requires conceptual skills in addition to the perception.

A ping-pong racket, which is an object perceivable by the subject as such, is quite different from a coded text that has to be perceived and, in addition, read and comprehended.

In order to understand this difference we can focus our attention on the theme of our perception, which is where the attention of the subject falls on.

When the subject perceives a common object, their attention falls directly on the perceived object. They are absorbed by such perception and everything else are simply left apart.64

The subject’s theme is the object in front of them. The subject is completely absorbed what is in front of them.

Wenn der Lehrer sagt: „Sei auf den Gegenstand aufmerksam“, so meint er dieses Aufmerken. Er meint nicht primäre Zuwendung im Sinn primären Bemerkens, sondern das In-der-Zuwendung-zu-den-Sachen-Leben, oder besser noch, das Sie-zum-Thema-Machen. Dazu genügt <es> nicht, den „Blick“ auf die Sachen <zu> richten, sie bevorzugend <zu> bemerken, und sei es auch primär <zu> be-merken. Sie müssen das Thema der Beschäftigung, der interessierten Zuwendung, der bevorzugenden Meinung sein.65

In the case of a written word, the subject perceives the word in its “pho-netic” aspects66, which is the bundle of graphems that constitutes the word as a physical object, but the subject’s theme is pointed through them to the meaning of such physical graphems.67

As we can see the thematic point is different in these two kinds of objects. The ping-pong racket has the theme in itself while the coded text such as a written page of a book points at its meaning.

The coded text has to be read and comprehended and therefore it is different from the common perceptual object that needs only perceptual skills.

A technology with noematic transparency is a technology that does not introduce the need of a reading and comprehension skills of the subject in a simple perceptual object. The object remains a perceptual object, even if with a different content.

64_{“Wir sind nicht in speziallem Sinn darauf aufmerksam, obschon es zeitweilig primär}

be-merkt wird” (Husserl 1986, p.21).

65_{Husserl 1986, pp.21-22.}

66_{This is a Husserlian distinction. See Husserl 1986, §3.}

67_{“Das Druckzeichen ist kein Gegenstand des „Interesses“. Es ist nicht unser Thema. Mit}

dem Wortlautbewußtsein ist verflochten das Bedeutungsbewußtsein, das sinngebende. Hier ist das Thema.” (Husserl 1986, p.22).

Augmented Reality and Phenomenology

DEPARTMENT OF DISCIPLINE UMANISTICHE

Ph.D. degree Curriculum Discipline Filosofiche

M-FIL/01

Augmented Reality

and

Phenomenology

The creation of “digital materiality”

and the knock-on effects of

such a futuristic potentiality

Nicola Liberati

Contents

I

Phenomenology and technology

5

II

A phenomenological analysis of Augmented Reality 79

List of Figures

List of Tables

Chapter 1

Introduction

1.1

Aim and Scope

Part I

Phenomenology and

technology

Chapter 2

Technology and the

perceptual world

2.1

The world’s constitution through

technol-ogy

2.1.1

Introduction

2.1.2

Optimum of the object

2.2

Which technology?

2.2.1

Criterion based on the content

2.2.2

Criterion based on the way the technology works

with the perceiving subject