Nina Bonderup Dohn
email: nina@sitkom.sdu.dk

Networked Learning 2006 Affordances -a Merleau-Pontian Account

Keywords: Affordance, ontology, epistemology, perception, agency, body, being-in-the-world, representation

In this paper, the concept of 'affordance' is given an ontological and epistemological explication building on a Merleau-Pontian view of human being as always already being-in-the world in a non-thematized, pre-reflective correspondence of body and world in the concrete activity. A dynamic, agent-centred, cultural-, experience-and skill-relative, but perception-independent, ontology is proposed for affordances. It is argued that this is more in line with the original Gibsonian understanding of the concept than a recent attempt by McGrenere and Ho, because the latter fall back upon the subject-object-dichotomy that Gibson was trying to transcend.

INTRODUCTION

Over the last decades the Gibsonian concept of 'affordances' [START_REF] Gibson | The Ecological Approach to Visual Perception[END_REF] has been widely used in research on human computer interaction, in discussions of the design of ICT systems as well as of their use [START_REF] Norman | The Design of Everyday Things[END_REF][START_REF] Gaver | Technology affordances CHI'91 Conference Proceedings[END_REF][START_REF] Mcgrenere | Affordances: Clarifying and Evolving a Concept[END_REF]. The agent-centred focus of the concept and the interrelatedness of action and perception implied by it at both a theoretical and a practical level make it appropriate for the analysis of the role of artefacts in human practice [START_REF] Norman | The Design of Everyday Things[END_REF].

However, underneath the seeming common acceptance of the analytical force of the concept lies a disagreement as to the exact ontological nature and epistemological status of an 'affordance'. [START_REF] Mcgrenere | Affordances: Clarifying and Evolving a Concept[END_REF], identify a number of variances in the use of the term and argue for returning to an understanding of the concept more in line with the original Gibsonian one. In agreement with this suggestion, I shall follow McGrenere and Ho in understanding Gibsonian affordances as "relative to the action capabilities of a particular actor" (McGrenere and Ho, 2000, p. 1). It will be argued, however, pace McGrenere and Ho, that this understanding implies a dynamic, relational, cultural-and skill-relative interpretation of the concept as opposed to the culture-independent, essentialist conception proposed by them. Furthermore, it will be claimed that an adequate account of 'action capabilities' cannot restrict itself to an analysis of "knowledge in the head or in the world" (cf. Norman, 1989, Ch. 3), but must consider the role of the body in determining both. In discussing this role, I shall draw on the phenomenology of [START_REF] Merleau-Ponty | Phenomenology of Perception[END_REF], arguing that his concept of 'body schema' is complementary to the concept of 'affordance' and illuminative for the sense in which "an affordance is neither an objective property nor a subjective property; or it is both if you like" (Gibson, 1986, p. 129). Examples from ordinary life involving the use of ICT and other artefacts will be discussed as illustrations of the theoretical arguments.

AFFORDANCES AS RELATIVE TO 'ACTION CAPABILITIES'

Gibson introduces the term 'affordance' in the following way: "The affordances of the environment are what it offers the animal, what it provides or furnishes, either for good or ill… [The word affordance] implies the complementarity of the animal and the environment." (Gibson, 1986, p. 127) Confining ourselves to human beings, an affordance is an affordance for someone, i.e. it only exists as an affordance relative to an agent. The fact of something being an affordance for someone is, however, according to Gibson, an objective matter, independent of the current needs of that someone and independent also of his/her ability in the concrete situation to perceive the affordance (ibid, p. 138f, p. 142f): A chair affords sitting for me regardless of whether I now want to sit or stand, and the computer mouse affords clicking for me regardless of the fact that for the moment it is hidden under the wealth of paper on my desk. The mouse would even afford clicking for me had it been designed to look like something else (e.g. a banana) so that I could not right away see that it was a computer mouse. On the other hand, it most definitely would not afford eating just because I perceived it as a banana. Interpreting Gibson's emphasis on the perception-and need-independent existence of affordances, McGrenere and Ho propose 2 claims: 1) It is necessary to distinguish as independent the existence of an affordance and the information specifying it 2) A person's ability to discriminate the information specifying a given affordance may depend on his/her experience and culture, but the existence of the affordance does not (McGrenere & Ho, 2000, p. 2). In other words, on McGrenere and Ho's view, the action possibility exists as an objective feature of the environment irrespective of culture and learning, but it may be necessary to learn to see that it is there. This view is highly problematic, especially when combined with a prior statement of the authors, according to which a fundamental property of an affordance is that it "exists relative to the action capabilities of a particular actor" (ibid., p. 1). The implication is a very unclear notion of 'action possibility for' and 'action capability of' a given person; i.e. a notion, in which the 'possibilities' and 'capabilities' of this person is without any reference to what he or she is actually able to do in any concrete situation. For what a person is actually able to do is definitely dependent on culture, prior experience and learning. Instead, the 'possibilities' and 'capabilities' of someone seem to have to be defined in relation to some abstract point or logically possible world, in which the person possessed all the capabilities he or she could possibly be conceived to come to acquire in whatever settings necessary. Whatever that means, and however one were to determine what those capabilities would be. Defined in this way, 'affordance' does not seem to be a particularly useful concept. In the context of design, it would seem to lead to designing only for 'potential users' with a total neglect of the actual skills of actual users, predictably with many frustrations of the latter as a consequence.

The problem here is not the relating of 'affordances' to the capabilities of a particular agent. Neither is the problem the emphasis on the distinction between affordances and perceptible information about affordances. Instead, the problem is the failure of McGrenere and Ho to acknowledge that not only do you often have to learn to see the use of something; you also in most cases have to actually learn to use it for it to present an 'action possibility' for you. And that, therefore, the existence of an affordance does depend on culture and experience in the sense of the German Erfahrung, though it does not depend on actual perception here and now and therefore not on experience in the sense of the German Erlebnis. It should be noted that when Gibson speaks of affordances as experience-independent, it is in this latter sense of the word (Gibson, 1986, p. 137 and p. 139-140). When above I emphasised that the chair for me afforded sitting and the computer mouse clicking irrespective of my perception and current needs, the point was that for me, with my physiologically, personally, and culturally dependent skills, they provide such affordances. For the 3-month-old baby, the chair does not afford sitting, it affords falling-off-and-hurting-oneself, and the computer mouse does not afford clicking, it affords putting-in-the-mouth. This does not mean that the baby cannot accidentally click the mouse whilst putting it in the mouth, but it means that this accidental click is not an 'action possibility' for the baby because it has not yet acquired the finger coordination skills necessary for making a click. And even if it had these coordination skills, it would still not have acquired the culturally dependent skills necessary for making use of the clicking in the further context of 'using the computer'. At most, the clicking would afford 'making-a-certainnoise' for the baby. Likewise, a chair flung back into the days of Cro Magnon would not afford him sitting; not because he would be physiologically unable to do so, but because culturally it would not present an 'action possibility' for him.

At this point, a comment must be inserted about the possibility of actions being performed towards an agent: Affordances are not only possibilities for action by the agent, they can also be possibilities of something acting upon him or her: An owl affords 'being-eaten' for a mouse, an angry parent affords 'being-scolded' for the child, and a webcam affords 'being-seen-by-someone-somewhere-else' for the person in the room with the webcam. This kind of affordances could be termed 'intransitive' affordances, implying that the action in question is not undertaken by the agent, but is happening to him/her. It should be noted, however, that 'intransitive' affordances are also relative to the action capabilities of the agent in question: In the case of the mouse, the owl's affordance for it depends on the relative strengths and fighting capabilities of the two animals. Likewise, it is relative to the personal and social skills of the child that the loud wording of an angry parent can amount to being scolded. On the face of it, the case of the webcam might seem different: a dog present in front of the webcam will be seen by the person receiving the signal, even though the dog has no computer skills. Actually, however, in this case one cannot reasonably say that the webcam 'affords' 'being-seen' for the dog at all, although it does afford 'seeing-the-dog' for the person receiving the signal: It does not afford 'being-seen' for the dog for the same reason that a computer game does not afford 'playing' for the 3-month-old baby, even when the latter is accidentally biting the click-button of the mouse at exactly the rate needed to shoot down the monsters of the game: It simply doesn't make the necessary sense for the dog and the baby, respectively; and it couldn't make the necessary sense for them given the action capabilities that they have. What this boils down to is the fact that affordance is necessarily tied to meaning, and that meaning is 'meaning for someone'. This is what McGrenere and Ho do not take into account when they claim that the existence of affordance is culture-independent. Or rather, they overlook that meaning is culture-and agent-dependent (though not 'subjective' in the sense of 'constructed by the individual') and ascribe it an ahistorical, essentialist existence. Therefore, they end up with affirming an essentialist ontology of affordances; in point of fact not returning to a Gibsonian relational perspective, but to the very subject-object-dichotomy that Gibson was trying to transcend in the first place.

'ACTION CAPABILITIES' ARE CAPABILITIES OF THE BODY

From the Gibsonian beginning, the concept of 'affordances' was meant to elucidate an important aspect of the way an animal lives, perceives, and acts in its environment. Of course, a very basic fact about animals, including humans, is that they have bodies and that they act by using their bodies. Interestingly, this fact has received relatively little attention in the discussion of the concept. Gibson himself had as his primary aim to give an alternative account of visual perception, starting from ecology rather than from the retinal image, and he stresses as essential that animals perceive as they move around in their environment, rather than from a still-life perspective (Gibson, 1986, p. 72). In this way, perception is made sense of within the wider context of the behaviour of a bodily being. However, the implications of this wider context remain largely implicit, focus being more on the information available in 'the ambient light' than on the role of the body in structuring the information. The concept of 'affordance' holds within it the incipience for an analysis of this role, by relating meaning and action capabilities, and by implying agency over and above mere moving around, but since this incipience has not been unfolded it has been largely overlooked in the reception of the term, especially in the HCI community. An interesting exception is [START_REF] Baerentsen | An activity theory approach to affordance[END_REF], in which an activity theoretical perspective on affordance is developed. In line with the common activity theoretical trend, however, this paper, though discussing the importance of social practice, understands action as conscious, goal-directed behaviour and so tends to overrate the importance of consciousness and representation in sense-making. The body is not viewed as in itself a resource of meaningful structuring of the environment, and therefore an essential aspect of agency is neglected in this paper as in others.

In striving to remedy this neglect, the fact must be taken seriously that we as human beings are bodily beings, and that 'action capabilities', whatever else they are, are capabilities of the body. Taking this fact seriously implies at least posing the question to which degree the body itself can possess knowledge or 'know how' and whether it has any role to play in determining the meaning of its actions. Is the body just that 'thing' which carries out the orders directed to it by the thinking human being? Are the 'action capabilities' of an individual actually the capabilities of his or her mind, which, when practiced, are coupled with the more or less mechanical 'executions' of these mental capabilities? This traditional Cartesian understanding of the relationship between mind and body seems to lie behind Norman's original proposals for better design, building as they do on the proposition that knowledge can be "in the head and in the world" (Norman, 1989, Ch. 3) and that "knowing what to do" (ibid, Ch. 4) involves either constructing a 'conceptual model' of the artefact to be used or 'interpreting information in the world'. Although in a prior chapter Norman has distinguished two kinds of knowledge, knowledge of and knowledge how, and has discerned the latter to be "difficult or impossible to write down… and best learned through practice" (p. 57f), this does not lead him to question the necessity of mental models in 'knowing what to do'. Quite to the contrary, 'knowledge how' is declared to be largely subconscious (p. 58) and is not mentioned again in the book; and in discussing the skilled typist, Norman asserts that he or she gains speed and accuracy as the information on the keyboard is memorized in the head (p. 56), i.e. as the information becomes 'knowledge of' for the typist. 'Knowledge of' is further asserted to include 'knowledge of rules' (p. 57), which, it is later implied, is actually essential to skilful behaviour: "Those of us who study these things believe that guidelines for cultural behavior are represented in the mind by means of schemas, knowledge structures that contain the general rules and information necessary for interpreting situations and for guiding behavior." (p. 85f) Passages such as these point readily to an understanding of skilful behaviour as primarily the mind's work, carried out only secondarily by its mechanical transportation carriage, the body. Such an understanding is fully compatible with the view of affordances advocated by Norman (both the original 1989-and the revised 1999view) according to which affordances (or "perceived affordances" in the revised view) "result from the mental interpretation of things, based on our past knowledge and experience applied to our perception of the things about us." (Norman, 1989, p. 219). However, the question is whether this view of the relationship between knowledge and affordance is adequate. Norman himself acknowledges that his account is at variance with many Gibsonian psychologists (ibid.), including Gibson himself (Norman, 1999, p. 39). And as Dreyfus has argued extensively, it is indeed questionable whether 'those of us who study these things' really ought to (that is, are justified if they) believe that skilful behaviour is rule governed [START_REF] Dreyfus | Mind over Machine[END_REF][START_REF] Dreyfus | What Computers Still Can't Do[END_REF][START_REF] Dreyfus | Phenomonological Description versus Rational Reconstruction[END_REF]. From an empirical point of view, Norman's claim is dubious, given the problems of cognitive computer scientists in handling the question of relevance and in constructing expert systems performing at the same level of skill as real experts [START_REF] Dreyfus | What Computers Still Can't Do[END_REF][START_REF] Copeland | Artificial Intelligence[END_REF]. Philosophically, the claim is equally debatable, resting as it does on two problematic assumptions: An ontological essentialist one according to which situations despite their seeming differences fall into disparate classes, each of which is characterized by fundamental features and/or structures. And an epistemological one to the effect that human knowledge of these fundamental features/structures and how to deal with them take the form of mental representations, e.g. as mental models and rule-following 'scripts' (for a critique of these assumptions, cf. [START_REF] Wittgenstein | Philosophische Untersuchungen[END_REF][START_REF] Heidegger | Sein und Zeit[END_REF][START_REF] Merleau-Ponty | Phenomenology of Perception[END_REF][START_REF] Dreyfus | What Computers Still Can't Do[END_REF]. From a common sensical as well as a phenomenological point of view, Norman's position simply seems to 'miss a link' between world and head: however is the information in the world to get into the head if not through the actions of the agent, a bodily being? Instead of postulating mental models and rule-governed scripts to account for action, a much simpler and yet phenomenologically more adequate explanation is provided by saying that first and foremost the body is itself acting in accordance with the requirements of the situation. An obvious rejoinder to Norman's description of learning to type well is that acquiring this skill is not a question of getting "knowledge about the keyboard from the world into the head", but into the fingers. A skilled typist will not necessarily be able to say where the keys are placed on the keyboard -until he or she is placed with the fingers on a keyboard (with or without the key labels showing). Once so placed, the typist will, however, be able to use the knowledge of the fingers moving around on the keyboard to reconstruct the arrangement of keys. Just like the rest of us can only remember passwords and pin-codes when standing in front of the machine we need them for. And even then, we do not remember these codes 'in the head', but through the movements of our fingers.

THE MERLEAU-PONTIAN NOTION OF 'BODY SCHEMA'

But what precisely is involved in saying that 'the knowledge is in the fingers'? Looking to the writings of Merleau-Ponty, one finds a non-representationalist view of knowledge and skills. For Merleau-Ponty, we are as bodily beings always already in the world in a pre-reflective, non-thematized (and therefore nonrepresentational) correspondence of body and world in the concrete activity we are engaged in. "Our bodily experience of movement is not a particular case of knowledge; it provides us with a way of access to the world and the object, with a 'praktognosia', which has to be recognized as original and perhaps as primary. My body has its world, or understands its world, without having to make use of my 'symbolic' or 'objectifying function'." (Merleau-Ponty, 1962, p. 140f) The body is "polarised by its tasks", has "existence towards them", thereby "collecting [itself] together … in the pursuit of its aims." (ibid., p. 101). In explicating this pre-reflective correspondence of body and world, Merleau-Ponty introduces the concept schema corporel, which confusingly has been rendered "body image" in the English translation. As argued by Gallagher, the translation ought to be body schema, leaving the former term to refer to the conscious representation a person may have of his or her body [START_REF] Gallagher | Body Image and Body Schema. A Conceptual Clarification[END_REF].

The 'body schema' is the way one has and knows one's body in action, through the demands and possibilities of the situation and the task one is undertaking in it. It is a focusing of the body on the concrete task, but, as a focusing is not a fixation, it is "open on to the world, and correlative to it" (ibid., p. 143), i.e. it leaves open the possibility of responding to and being polarized by other tasks (ibid. p. 141). As a simple example of this 'knowing oneself through the activity one is undertaking', Merleau-Ponty mentions the activity of smoking a pipe (ibid., p. 100). In so doing, one knows where one's arm is, not in objective terms of coordinates and angles in relation to the trunk of one's body, but through knowing where the pipe is because one is enjoying it. The body itself is not thematized at all and therefore one knows it only through living it in the action. Similarly, this 'knowing the body through living it' is the reason why one can be totally unaware of habitually performing a specific gesture, but, when told by others, nonetheless one can recognize it as one's own action by performing it with awareness and feeling the familiarity of it. Importantly, the body schema is not equivalent to the physical body. A dramatic example of a lack of equivalence, discussed by Gallagher, 1995, as well as Merleau-Ponty, is the case of phantom limbs: People who have had a limb amputated often report that they can still feel it and actually act as if it were still there, for example by getting up and starting to walk across the room, only to realise as they fall that the leg is not there anymore. Mentally, as part of the body image, such a person will certainly know that the leg has been taken off, but he or she is acting body schematically to the demands of the situation with a body schema that has not yet accommodated to the new state of affairs.

The lack of equivalence between body schema and physical body is, however, also the reason why a person can learn to use a prosthetic device as a substitute for an amputated limb, and, in general, why we can learn to use artefacts to probe and manipulate our surroundings. The blind person senses the world directly at the tip of his/her cane, not indirectly through an interpretation of the movements caused in the hand. Likewise the sports fisherman senses the fish at the tip of his fishing rod, and experienced bicyclists or drivers sense the road through the wheels of their bike or car. In using an artefact, one is incorporating it into one's body schema and acting from it as part of the phenomenal body, not through it from the borders of the physical body. This phenomenon has been discussed extensively within phenomenology [START_REF] Merleau-Ponty | Phenomenology of Perception[END_REF][START_REF] Gallagher | Body Image and Body Schema. A Conceptual Clarification[END_REF]and 1995[START_REF] Polanyi | The Tacit Dimension[END_REF][START_REF] Leder | The Absent Body[END_REF]. Recently it has been discussed also by Kaptelinin, who has given it an activity theoretical interpretation under the heading of 'functional organs' [START_REF] Kaptelinin | Computer-Mediated Activity: Functional Organs in Social and Developmental Contexts[END_REF]. Coming back now to the sense in which the skilled typist has 'knowledge in the fingers', this is precisely in the body-schematic sense: In typing, the keyboard is incorporated into the body scheme of the typist and therefore he/she is meeting the demands of the situation by acting from the keyboard as part of the body. As Merleau-Ponty says, actually also discussing type-writing: "To know how to type is not, then, to know the place of each letter among the keys [pace Norman, my comment, NBD], nor even to have acquired a conditioned reflex for each one, which is set in motion by the letter as it comes before our eye… It is knowledge in the hands, which is forthcoming only when bodily effort is made, and cannot be formulated in detachment from that effort… When I sit at my typewriter, a motor space opens up beneath my hands, in which I am about to 'play' what I have read." (ibid., p. 144). In sum, action capabilities are capabilities neither of a Cartesian mind, nor of a Cartesian pure mechanical body (therefore a skill is not a conditioned reflex). Rather, the Cartesian mind-body-dichotomy must be transcended by a concept of agency as the acting of a bodily being where the latter is seen to imply concepts traditionally viewed as 'mental', such as 'intentionality', 'meaning' and 'knowledge'. And where, conversely, 'knowledge and meanings in the head' depend greatly on 'knowledge and meanings of the body'. 'Being a body' involves 'having a world' and action capabilities are capabilities of the agent as a bodily being.

A MERLEAU-PONTIAN ACCOUNT OF AFFORDANCES

Returning to the concept of 'affordances' with the Merleau-Pontian notion of 'body schema', the two concepts emerge as complementary ways of referring to the fact that concrete situations are, objectively seen, meaningfully structured relative to the actual skills of a particular agent. Thus, 'affordance' signifies that meaning is in the world, not in the head, and 'body schema' signifies that the world is meaningful because of what we can do in it. Together, they reciprocally signify that we as human beings live in a world not of our own mentalistic making, the meaning of which nonetheless transforms in accordance with what we learn to do. Even more importantly, the complementarity of the two concepts implies an interdependency of body and world, which is experientially, epistemologically, and, in respect of meaning at least, also ontologically primary. Finally, the dual notions of 'body schema' and 'affordance' suggest an understanding of agency as an immediate 'doing of what the situation calls for', i.e. an 'attuning of the body to the demands and possibilities of the situation' that does not rely on representation of these demands and possibilities. In the following two subsections, I shall draw on this basic reciprocity in giving a Merleau-Pontian account of affordances, focusing on the ontological nature and epistemological status of the latter.

Perceiving Affordances -the Epistemological Question

Fundamental to the Merleau-Pontian understanding of perception is its interwovenness and dependency on agency. Though of course we sometimes represent and consciously think about what we perceive, perception of something does not imply representing it. Instead, it implies that the situation presents itself to us as bodily agents with a certain figure to-be-acted-upon. Perception is first and foremost presentation-in-action to the agent (not solely to the mind) of meaning in the world, not a representation in the head of this meaning. Accordingly, perceiving the affordances of a given situation does not necessarily mean being consciously or sub-consciously representationally aware of them; rather it means body-schematically acting upon them in an attuning to the possibilities that they pose. When a standing conversation becomes tiring for the legs, one responds to the affordance of a chair by sitting down, often without being representationally aware neither of the act nor of the chair itself, awareness being only on the conversation held. Likewise, when the long-sought-for words for a passage in a research paper finally come to mind, the mouse is grabbed, pushed and clicked, and the keys of the keyboard struck, without any representation of these operations being involved, awareness being fully absorbed 'out there' in the words presenting themselves on the screen of the computer.

Importantly, perception always has a figure-background structure. This point is often illustrated with 'gestaltswitch pictures' where a picture can be seen in two different ways, as non-simultaneously representing two gestalts, where the background of one gestalt is the gestalt of the other and vice versa. An example is Rubin's famous Peter-Paul Goblet [START_REF] Dreyfus | What Computers Still Can't Do[END_REF]. However, the point is more general than the discussion of such rather special pictures might lead to expect: Quite generally, the background of a picture determines its figure as much as the figure itself, both banally in establishing the outline of the figure, and more significantly in deciding its meaning. A smiling face means something very different when portrayed on the background of a flowery meadow and on the background of starving children. And of course, the meaning of the picture is perceived by the observer on the background of his or her knowledge and experience (in the sense of the German Erfahrung); part of which will be representational and part of which will be bodily incorporated as ways the world make actionable meaning.

These observations about the perception of pictures apply similarly to the question of perceiving affordances. Concrete situations present themselves with the figure of action possibilities relative to the task currently undertaken by the agent. Given the openness of the body schema to being polarized by other tasks, the current one does not preclude noticing affordances unrelated to it, but, depending on one's degree of immersion in the given activity, one may very well actually fail to take regard of other affordances, unless these are in other ways very important. When fully engrossed in writing a paper, the chilliness of the room may not be noticed, though it does afford being cold. Typically, in such a situation, one's first reactions to the non-task-related affordance are body-schematic and non-representational, e.g. one may without thinking about it shuffle one's feet, rub one's legs or maybe even get up and close the window. Only if the chilliness persists does one become aware of it and of being cold. Again, the perception of this affordance takes place on the background of the knowledge and experience of the agent. Though feeling cold is not dependent on experience and culture, what one does in acting upon the feeling is, at least to some extent. A three-month-old will cry, a grown-up Viking anno 1000 might have put on an extra garment or lit a fire, a grown-up Dane of today probably adds a sweater, closes the window, or turns up the central heating. Importantly, the affordance of the chilliness presents itself 'with a handle on it'; not just as a state of affairs to be contemplated, but directly as demanding certain actions in response. Our bodily existence, with the physiological, personal, cultural needs and skills each of us possesses, is the background upon which we perceive and act in the situations we come in.

In regard to the epistemological status of affordances, a Merleau-Pontian account therefore holds: First, we do not always perceive all the affordances of the environment; quite the contrary, we first and foremost perceive the ones relevant for the task we are undertaking. Second, perceiving affordances is not primarily a question of representations and mental models; rather, in perception, situations present themselves directly as bodyschematically to-be-acted-upon. Third, we are body-schematically able to take account of or attune to affordances of the situation without being representationally aware of doing so. Fourth, the meaning a situation has for us and specifically the affordances it offers us stand out as a figure on a background, where the latter has a decisive role to play in determining the former. Fifth, the figure-background structure of the situation is perceived on the background of our physiologically and culturally dependent bodily existence, with the skills, experience, and knowledge incorporated herein.

Illustrative of these points is the phenomenological consideration of the introduction of a webcam into a synchronous oral or written ICT-learning situation. Participants in such situations often claim that after a while they neglect the webcam and concentrate on the words said or written; a claim which is backed by the fact that they actually seem only rarely to look at it. However, though it may be that the participants do not make direct positive use of the affordance of the webcam in their communication, its affordance plays a large role in the structuring of the meaning of the situation, changing the figure of it to one in which participants 'can be seen'. Though they may not be representationally aware of the webcam at all, it is part of the background of the situation, posing demands for and setting restrictions on appropriate action in the situation. And these demands and restrictions are taken into account in the participants' body-schematic non-representational attuning to the situation. In consequence, participants change their behaviour as compared to ICT-learning situations without webcams, though they may not be aware that they do. Without a webcam, participants may (and many say they do) fetch coffee, skim through a letter or talk with other people in the room (if sound is not automatically transmitted). Such actions will not be undertaken with a webcam, or, if an interruption is absolutely necessary,it will not be undertaken without apologizing first.

As the last point, it must be emphasized that we of course sometimes fail to perceive something or misperceive it for what it is not, for which reason we sometimes fail to act on an affordance which it might have been advantageous to have taken into account, or alternatively act as if the environment offered an affordance for us which it does not. The webcam may be hidden to us, or we may misperceive it for an audio recorder or a beamer and so not act appropriately. This possibility of erroneous perception leads on to the next section, which treats the ontological question of the nature of affordance and more specifically asks, to which degree affordances are agent-dependent.

The Existence of Affordances -the Ontological Question

The ontological nature of affordances is a dynamic, relational, cultural-, experience-and skill-relative one. Affordances are the actionable meanings of objects for a particular agent and as such their existence must be determined relative to the body-schematic space of possible actions of that agent. And as this body-schematic space of possible actions changes over time as the agent incorporates new experience, knowledge, and/or skills into his body schema -or, more negatively, as he or she forgets/loses skills etc. formerly possessed -what an object affords a specific person is in most cases transformed more than once throughout his or her life.

Claiming that the existence of affordances is to be seen as relative to the body schematic space of possible actions of a particular agent, however, is not equivalent to postulating a relativistic, subjectivist ontology of affordances. The objects in the environment exist independently of the agent, and they have actionable meaning for the agent, independently of his or her current needs and actual perception. As Gibson maintained, meaning is objectively there in the world, only, as it has already been emphasized, meaning is necessarily meaning for someone. Not in the sense that this 'someone' must necessarily be aware of the meaning here and now, but in the sense that it has meaning in relation to what he/she is body-schematically able to do. From a Merleau-Pontian point of view, it is in this fundamental relating of meaning-in-the-world to bodily doing-in-the-world that the Gibsonian transcendence of the subject-object-dichotomy consists.

Clarifying this relational, yet not relativistic, ontological nature of affordances further, not only does an object's affordance for someone not depend on his/her perception thereof; neither does it depend on whether anyone ever perceives this particular object to have this affordance for him or her. It makes sense to say that the computer mouse hidden under the paper heaps on my bookshelf affords clicking for me and my colleagues, though it actually has never been clicked (because I misplaced it there right after I got it) and never will be clicked, because it eventually will be thrown out by mistake together with the unsorted paper heaps. But it only makes sense to say this, because my colleagues and I are able to use that kind of device. And 'are able to', it should be noted, means that we in point of fact exercise this action capability with other computer mice in concrete situations. Affordance is therefore relative to action capabilities understood as body-schematic possibilities of actions, (i.e. actions actually sometimes exercised) with or in relation to objects qualitatively identical or at least sufficiently similar with the one in question, but not necessarily numerically identical with this particular exemplar.

A last comment on the ontological nature of affordances: As McGrenere and Ho note [START_REF] Mcgrenere | Affordances: Clarifying and Evolving a Concept[END_REF], referring to Warren, 1995, 'affordance' is not a binary concept, though it has often been used as if it were. Chairs afford sitting for modern agents above a certain age, but, relative to a particular one of these agents, some chairs afford the activity better than others. Most (but not all) chairs for 3-year old children afford sitting on for grown-ups, too, but not nearly as well as chairs designed for grown-ups. Again, the relative degree of affordance of an object for a given person is relative to his/her body-schematic space of possible actions, as this is determined by his/her physiology, experience, knowledge, and skill, acquired in the socio-cultural settings he/she has partaken in.

CONCLUDING REMARKS -WHY CARE?

In this paper I have presented a theoretical elaboration of the ontological nature and epistemological status of the concept of 'affordances', based on a Merleau-Pontian understanding of human beings as always already in the world in a non-thematized, pre-reflective correspondence of body and world in the concrete activity. But why care? Why should such ontological and epistemological considerations matter at all for the design and use of ICT in network learning? My claim is that they do matter. The concept of 'affordance' is an important one, because its fundamental ecological focus on meaning as an aspect of the interaction of agent and environment can elucidate notions of use, usefulness and usability theoretically, and can guide the design for these notions practically. However, since the force of the concept lies in its ability to transcend the subject-object-dichotomy, it is essential to be clear about ontological and epistemological issues. Otherwise, chances are that the implicit understanding of the concept will unwittingly draw on precisely this dichotomy, leading to the well-known philosophical positions of essentialism (e.g. [START_REF] Mcgrenere | Affordances: Clarifying and Evolving a Concept[END_REF] and phenomenalism (e.g. [START_REF] Norman | The Design of Everyday Things[END_REF], respectively, only clothed in a new wording. The consequence for design are very unhelpful concepts: As noted, the essentialist interpretation of 'affordances' as related to 'action capabilities' understood without reference to experience, knowledge, and culture, would lead one to design for mysterious 'potential users' instead of actual ones. On the other hand, the phenomenalist position that affordances exist exactly as they are perceived makes misperception and mistakes inexplicable and ultimately denies the possibility of bad design. Only with a relational, dynamic, agent-centred, and skill-relative conception of affordances can one design real objects for real users whose skills develop and possibilities increase as their experience gains. And only if one understands perception as interwoven with body-schematic being-in-the-world will one be able to focus one's design process on creating the best possible design: the one that does not break the primary correspondence of body and world by making reflection necessary. Designing is not about making mental representations easy to construct, it is about making representation unnecessary.


Introduction

In traditional Anglo-American philosophy knowledge is understood as a static, linguistic representation of the world. This means that knowledge is understood to be necessarily propositional: Knowledge is 'knowledge that'. In consequence, the everyday concepts of 'knowing how' and 'knowing what' (often also referred to as a 'knowledge of') exemplified in sentences like "He knows how to drive a car" and "She knows what red looks like", respectively, are either neglected or subsumed under the category of 'knowledge that'. The aim of this paper is to show the problematic nature of analyses based on this presupposed primacy of linguistic knowledge and I shall argue that the knowledge we possess in practice apart from 'knowledge that' includes 'knowing how' ('practical knowledge') and 'knowing what' (or 'experience', as I shall also term this notion). These three kinds of knowledge form a synthetic unity which I shall call 'knowledge in practice' and which, I shall claim, can be characterised as a perspective that makes aspects of a situation stand out as relevant and important. The paper will be structured into three main parts: First, to focus attention on the subject matter I shall give some examples of 'knowledge in practice'. Next, I shall try to extract some philosophical implications of these examples for the concept of knowledge, and lastly, I shall consider the role the body plays in the acquisition of 'knowledge in practice'. I shall end the paper with a few concluding remarks that sum up the main points of the argument.

Examples of 'knowledge in practice'

My first example concerns the expert practitioner in medical practice, for example a nurse or a doctor. These kinds of practitioners definitely have a large amount of linguistic knowledge -in their education they have learned theories of for example anatomy and physiology and have also acquired theoretical knowledge of a number of specific malfunctions and diseases (the doctor of course has a h igher degree of theoretical knowledge than the nurse). At the same time they have to have a large amount of practical knowledge: Just to mention a few obvious examples, the surgeon must be able to make his cuts the right way, the doctor working with fractured bones must know how to put a broken leg together again and make the right plaster cast for it, and the nurse must be able to apply and change a bandage. Actually this is not a very good way of putting the point, because it sounds as if the 'know that' and the 'know how' of the medical practitioner were totally distinct from each other, which is really the opposite of what I wish to argue. To see what I mean it helps to consider Mi-chael Polanyi's description of what it is the medical student being introduced to radiography is learning [START_REF] Polanyi | Personal Knowledge -Towards a Post-Critical Philosophy[END_REF].

At first, when the student is presented with an X-ray picture of the lungs all he sees is the ribs -he cannot see the lungs and certainly not any specific traits in them, so he understands nothing of what the expert radiographers are saying to one another. After having seen several such pictures, though, the student gradually becomes able not only to make out the lungs, but also to discriminate between traits due to natural variation and traits caused by illnesses of various kinds. The student is here learning to identify the terms he has until now only been reading about in his textbooks -that is to say: The linguistic knowledge of the books acquires meaning for him because he is learning how to see relevant features. In other words he only understands the linguistic knowledge when he knows how to discriminate the features it refers to. And since 'knowledge that' in any reasonable interpretation must involve understanding, not just reproducing, the relevant sentences, 'know that' and 'know how' are seen in this case to be inextricably bound up with each other. Furthermore, these two kinds of knowledge are also interdependently related to the third kind of knowledge, 'knowledge of', in that they both are made possible by the student's experience of a wide variety of X-ray pictures. In effect, when the student has learned the required pulmonary radiography he knows what characteristic traits of normal and sick lungs look like and this supplies him with the basic understanding of the textbook theories as well as makes him able to discriminate such traits in new pictures. In other words, what the student is acquiring is a form of knowledge that is a unity of 'know how', 'know what' and 'know that' -a unity, in which the three aspects mentioned ontologically speaking are necessarily interrelated and even for analytical purposes can only be partially separated. This unity I shall call 'knowledge in practice'.

Actually, 'knowledge in practice' is to be understood as more than just the interrelated combination of the three aspects. As I see it, 'knowledge in practice' is a kind of perspective with which we meet the situation; a perspective that lets aspects of the situation stand out as relevant and important. This is exactly what happens when the radiographer sees an X-ray picture of the lungs: His 'knowledge in practice' makes certain features that the novice student literally cannot see noticeable for him and thereby lets him identify the pulmonary disease of the patient. In a less literal sense it is also what happens in medical diagnosis in general, and, I would say, actually 'knowledge in practice' as a perspective on the situation is a key concept in understanding medical practice as such: In diagnosing and treating a patient the 'knowledge in practice' of the doctor makes certain aspects of the patient's story as well as certain traits in the patient's physical and psychological appearance stand out as important while other aspects are seen as irrelevant or are not noticed at all. In interacting with the patient the perspective of 'knowledge in practice' makes certain parts of the theoretical knowledge of the doctor the relevant ones to relate to and makes certain forms of action seem appropriate, which is to say that the perspective facilitates the doctor's 'knowing how to' react to the patient. Of course the former experience of the doctor is essential in this context -his encounters with prior cases supply the 'knowledge of' necessary for him to be able to classify a given case as a certain kind of disease. This is not to say that a given case will be exactly like any other he has experienced before -on the contrary, every situation will be unique in its own complexity -it is rather to say that on the basis of the aspects of the situation that the perspective lets stand out as relevant the situation will be experienced as analogous though not fully similar to other situations the practitioner has been in. It is important to emphasise that the three kinds of knowledge, 'know how', 'know that', and 'know what', here as in the more specific case of radiographic diagnosis will be aspects of a unity and that the interrelated nature of the aspects only allows a (partial) analytical, not an ontological separation: The 'knowledge of' of the medical practitioner supplies meaning to his theoretical knowledge and is at the same time the basis on which he performs adequately -it is for example an integral part of knowing how to conduct an operation to know what it feels like to hold and use the knife the right way.

Likewise, linguistic and practical knowledge will be intertwined -theoretical knowledge about the heart and the way it functions is for example of the greatest importance in the transplantation of an organ of this kind. In sum, knowledge in medical practice is a 'knowledge in practice', i.e. a unity of 'know how', 'know that' and 'know what'; a unity that essentially involves more than its aspects in that it constitutes a perspective on the situation. To try to capture this last point, I shall speak of the unity as a synthetic unity, thereby indicating that the three aspects synthesise to a whole that involves more than its parts.

A piece of evidence for the existence of this 'more' is supplied by reports of medical practitioners (e.g. Benner,1984[START_REF] Josefson | The Nurse as Engineer -the Theory of Knowledge in Research in the Care Sector[END_REF] that they not uncommonly have the experi ence when confronted with a patient that they 'can see that something is wrong' though they 'cannot say what it is'. In this case, the perspective of 'knowledge in practice' lets the situa tion present itself as 'unusual', 'strange' or 'wrong'; and, it should be noted, the presenta tion moreover has the form of a gestalt:

The practitioner is not able to point to definite features that are not as they should be, rather the appearance of the patient as a whole gives him the overall impression that something is wrong. The knowledge of the practitioner is here not a linguistic knowledge since he cannot determine what it is that is disturbing him; neither is it a practical knowledge since he is not doing anything. Of course, his former experience has a great role to play in this connection -it is exactly his (not explicit) knowledge of the ways healthy and ill people look, acquired through the interaction with a great number of patients with a large variety of diseases, that makes it possible for him now to have this presentation, i.e. to view the patient in this way. Still, he is most probably not relating to any one (or even just a few) of these experiences -if he were, he would presumably be able to say at least something like "Because of this-and-that, this person reminds me of so-and-so who had such-and-such a problem"; which is to say that he would actually to some extent be able to describe what it is that strikes him as wrong. In sum, there is more to this presentation than just the interrelated combination of 'know how', 'know that', and 'know what'.

After this rather lengthy description of the knowledge of medical practitioners, I shall give two shorter examples of 'knowledge in practice' to show that the phenomenon is widespread -actually, I would claim that knowledge understood as something people (can) use in specific contexts (as opposed to an abstract mental entity that can be possessed without ever being put to use) always has the form of 'knowledge in practice', but within the limits of this paper it is not possible for me to try to prove this more substantive claim. The first of these examples concerns car driving understood not only as the actual driving of the car but as an activity one undertakes in a wider context -for example as part of the process of going to work or to see some friends. Even when the only reason for driving the car is that 'one feels like a ride' this activity still is not 'just driving' since it has a meaning in terms of precisely this goal and of the fact that one has the opportunity to pursue it. Seen in this light there is quite a bit of 'know that' involved in car driving: Apart from knowledge of traffic rules and perhaps of some facts about the possible speed and acceleration of various car brands -facts, that it might be contested (as Hubert and Stuart Dreyfus do, [START_REF] Dreyfus | Mind over Machine -The Power of Human Intuition and Expertise in the Era of the Computer[END_REF]) play a role in expert as opposed to novice driving -the driver will make use of explicit knowledge concerning for example which roads to avoid during rush hours, which routes provide the more interesting scenery and which ones are the shortest etc. On the other hand, driving is definitely to a large extent a 'know how' -no amount of even extremely detailed rules will make up for the expert driver's intuitive grasp of the situation and his smooth way of responding to it. And certainly experience is very important here; i.e. experi ence of the way it feels to drive, e.g. how the car behaves when manipulated in certain ways, as well as experience of a variety of situations with different weather conditions, traffic density, road conditions etc. As in the case of medical practice, I furthermore wish to contend that the three kinds of knowledge involved in driving form a unity: It is difficult if not impossible to say where the experience of driving stops and where the 'know how' begins, and likewise, the 'know that' involved in the making of specific decisions structures the way the 'know how' is practised. As for the relation between 'know that' and 'know what', the experience acquired in specific situations will be part of what supplies meaning to the utterances one would make concerning these situations. At the same time, the 'knowledge in practice' of the driver, like the 'knowledge in practice' of the medical practitioner, is more than the interrelated combination of the three kinds of knowledge:

Here, too, it has the form of a perspective that lets aspects of the situations the driver comes in present themselves as relevant and important. To the novice all other drivers seem the same and the cars are only seen as dangerous obstacles to be avoided. As he gains experience, though, the perspective of the novice becomes more sophisticated so that he is able to tell the difference between aggressive and timid driving and to notice features he would not have seen before, like a tendency to sway a bit to one side, that prepare him for the manoeuvres of others even before they signal these manoeuvres unequivocally. And once in a while he can come to have the feeling that there is 'something wrong' with the way someone is driving, even though he is unable to say what it is that disturbs him, which is to say that the perspective here, too, is giving him an apprehension of the situation in the form of a gestalt; i.e. an apprehension that cannot be identified in terms of any constituent parts. In other words, the 'knowledge in practice' of the driver is a synthetic unity that is more than its constituent aspects.

My last example is taken from a practice where knowledge is normally considered to be exclusively linguistic, namely the practice of doing natural science. To make the example as short as possible I shall concern myself with only one kind of natural science and have to this end chosen physics. My point is here that even though the physicist of course possesses explicit linguistic knowledge to a very high degree there is also a practical knowledge and a 'knowledge of' involved in doing physics and that actually knowledge here, as in the former cases, has the form of a perspective on the situation that lets relevant aspects of it present themselves. Furthermore, I wish to contend that this is so not only in experimental, but also in theoretical science. This is most easily seen when one considers the fact first discussed by Thomas Kuhn [START_REF] Kuhn | The Structure of Scientific Revolutions[END_REF] that students often find it exceedingly hard to solve the problems at the end of their textbook chapters even though they claim to have understood every word of the text. The reason for this can be described by saying that they lack the 'know how' necessary to solve the problems, as well as the experience of working with and solving a large variety of related problems. This way of putting the matter, however, though correct, does not allow for the fact that the most important thing which the students lack is the right perspective on the problem. In classical mechanics, for example, it is of advantage when solving the movement problem of a pendulum to view it as 'like' a block on an inclined plane, but seeing this likeness is not just a matter of possessing textbook knowledge -rather it is a question of having a perspective on the pendulum that lets the relevant similarities stand out as significant.

This perspective is what makes the 'know how' of solving the given problem possible and is also what is needed for a full understanding of the linguistic knowledge connected to it. Furthermore, these two kinds of knowledge are clearly intertwined with each other, as they are, too, with 'know what': It is through working with concrete problems -through experiencing specific ways of handling physical situations and, very importantly, through having the 'aha-experiences' of suddenly 'seeing' the solution to a given problem -that it becomes possible for a person to acquire the 'know how' of problemsolving and the full understanding of the explicit knowledge simultaneously and in rela tion to one other. In sum, here, as in the other cases described, what the students need is a 'knowledge in practice', i.e. a unity of the interrelated aspects of 'know that', 'know how', and 'know what' -a unity that is at the same time more than just the combination of these aspects in that it forms a perspective on the situation; or, as one might also put it, in that it gives a 'feel for physics' (cf. [START_REF] Kanigel | Apprentice to Genius. The Making of a Scientific Dynasty[END_REF].

With these examples I hope to have made plausible the claim that at least in a wide variety of practices, ranging from ones where explicit linguistic kno wledge has a very great role to play to ones where practical knowledge is dominant, the knowledge we possess has the form of a perspective. Likewise, I hope to have rendered it reasonable to say that even though one of the three discussed kinds of knowledge constituting 'knowledge in practice' ('know that', 'know how', and 'know what') may be dominant in certain practices the other two kinds will also be present and necessary for an adequate way of relating to specific situations. In the next section I now wish to take a closer look at the notion of 'knowledge in practice' and at the relation between its constituent aspects. The purpose will be to elucidate the philosophical implications of the examples given in this section.

'Knowledge in practice'

A point very much in need of clarification, given the foregoing, is the relationship between experience and 'knowledge in practice'. I have tried to show that 'knowledge in practice' involves more than just the 'knowledge of' acquired in concrete situations, but on the other hand I have emphasised the importance of this latter kind of knowledge as well for 'knowledge in practice' as for the other two constituent elements 'know how' and 'know that'. The question of the role the two phenomena play in the acquisition of knowledge therefore remains to be answered.

Basically, as I see it, 'knowledge in practice', at least in some primitive form, will always be necessary for the acquisition of experience: It is a condition of experiencing that certain aspects of a situation in some sense be noticed to be important and this is precisely what the perspective of 'knowledge in practice' renders possible, in that it lets certain features of a situation stand out as the relevant ones. This is not to say that 'knowledge in practice' determines what we experience -what stands out as noteworthy features may very well be features that are surprising or unexpected.

Rather, it is to say that it is only because of the perspective that anything can be noticed as 'surprising' in the first place. What the perspective does is to let the world present itself in certain ways -a sick person simply looks different to the doctor than to the layman, just as the same traffic situation may seem chaotic to the novice and relatively easy to handle to the expert driver. Therefore, the expert has the possibility of acquiring other experiences, or at least experiences that are much more differentiated and sophisticated, than the novice. In this way, 'knowledge in practice' is a prerequisite for experience.

At this stage it should be noted that the experience acquired in a given situation is not necessarily one of which we are mentally aware in any strict sense. To explain what I mean by this it is helpful to introduce the terminology of Polanyi who speaks of our attention as having a focal and a subsidiary part [START_REF] Polanyi | Personal Knowledge -Towards a Post-Critical Philosophy[END_REF]): When we act the focus of our attention is the goal of our action not the action itself -when hammering, for example, we concentrate not on the hammer or on the hand holding it, but on the nail or, rather, on the board that the nail is to be driven into. At the same time, though, I would claim that we are maintaining a subsidiary awareness of the action itself: Were it not for this kind of awareness we would not be having any experience at all since our focal attention is directed elsewhere -we would not be getting the 'feel of hammering' and actually it would be a mystery how we ever succeeded in improving through practice. The point I now wish to make is that quite a lot of the experiences that we acquire while partaking in practice are acquired in this sub sidiary way, which means that we are not able to account for them and, most often, are not even aware that we have had them. The driver concentrated on the traffic situation of which he is a part is not focally aware of all the movements he makes with the car in order to adjust to the situation, but still he (ideally, at least) becomes more experienced all the time because he notices subsidiarily what he is unaware of focally. Actually, I would claim that a number of the aspects one finds important in a situation are not noticed focally, but only subsidiarily, and that one reacts to them on the basis thereof. The doctor, for example, who directs his attention towards the specific illness of a given patient may not focally be aware of all the details of the appearance of this patient, but still he most probably is noticing many of these details subsidiarily and accommodating his treatment accordingly. Therefore, when I emphasised above that the perspective of 'knowledge in practice' makes it possible to find aspects of a given situation relevant it is to be understood that this process does not have to be obvious to the experiencing person, but can very well take place subsidiarily.

The reason for the subsidiary nature of many of our experiences is as already suggested that 'knowledge in practice' is an integral part of our interaction with each other and the world through our participation in practice. In other words 'knowledge in practice' is not a static, linguistic representation of the world as traditional Anglo -American philosophy has it -instead, it is an ever evolving phenomenon directed towards action; a phenomenon, large parts of which are not and cannot be articula ted in words. Perhaps 'knowledge in practice' could be described as a preparedness for actions and events in the world. In any case, in relation to the question of experience, the nature of 'knowledge in practice' implies that it is in practice that the w orld presents itself in some ways rather than in others and therefore it is in practice and in relation to practice, i.e. very often in action, that our experiences are acquired. Thus, experience acquisition is something which we seldom, if ever, undertake solely for its own sake: It is something that happens in the midst of activities motivated by other goals. This, I think, explains why we come to have many of our experiences in a subsidiary way.

A further point I wish to make concerning the relationship between experience and 'knowledge in practice' has to do with the primary role experience to my mind plays within the unity of 'knowledge in practice' with regard to linguistic and practical knowledge. As has already been implicit in the analysis of the examples given in the last section I want to claim that experience is a prerequisite for the acquisition of 'know that' and 'know how'. The dependence of 'know how' on 'know what' is, I think, uncontroversial: Only through experience is it possible to acquire the 'feel of' something and to get to know the right way to react in specific circumstances. As for the relation between linguistic knowledge and experience, I would contend that a significant part of the meaning of a great number of words and expressions, though not all of it, consists precisely in the non-linguistic experience of certain kinds of phenomena, i.e. in 'know what'. This was seen to be the case in the example of radiography, in which the student first fully understood the textbook descriptions when he had had the experience of perceiving the relevant traits in the lungs of sick and healthy people. It was seen, too, in connection with the physics students whose full understanding of the theories of physics included experiences of working with and solving problems related to these theories. In a more everyday context it is also the case for a wide vari ety of words and expressions like 'red', 'pain', 'love', 'what it feels like to be addicted to smoking', etc.: Though part of the meaning of the word 'red' definitely is made up of other linguistic expressions like 'different from blue', as I see it, there is also a significant part that relates to the actual experiencing of red things. A blind person simply does not know what the term 'red' means in the same sense as a sighted person does.

Summing up, I want to say that 'knowledge in practice' is necessary for the acquisition of experience and also for linguistic and practical knowledge. This is so, partly because these two types of knowledge are both dependent on experience and partly because even when in specific situations the 'know how' has already been acquired and the meaning of the terms involved are known on beforehand (most probably, at least to some extent, because of earlier experiences), the perspective of 'knowledge in practice' is still needed both to make aspects of the given situation stand out as the relevant ones to react to and to formulate into sentences of linguistic knowledge, and as something to which one can relate the 'know that' already in one's possession. Since 'knowledge in practice' lets the world present itself in some ways rather than in others, it is on the basis of 'knowledge in practice' that our 'know how' and 'know that' are structured in concrete situations.

Given this analysis, however, the question arises how 'knowledge in practice' can at the same time be a prerequisite for the three kinds of knowledge discussed and also consist in the synthetic unity of precisely the same three kinds of knowledge? The answer to this question is in my opinion relatively simple: As mentioned above, 'knowledge in practice' is not a static entity, but is an ever evolving phenomenon.

Therefore, the 'knowledge in practice' that a person has at a given moment renders possible the acquisition of new experience and with it linguistic and practical knowledge, by letting aspects of the given situation present themselves as important.

In this process, it should be noted, the three aspects of 'knowledge in practice' are not acquired separately from one another -instead they are acquired in an already united way and in relation to the existing 'knowledge in practice' into which they are incorporated. The result of the incorporation process is a modification and differentiation of the person's 'knowledge in practice' which means that the perspective with which he afterwards meets the world has a higher degree of sophistication. And this, in turn, lets other or more differentiated aspects of a given situation stand out as relevant and important, which again lets new 'know what', 'know how' and 'know that' be acquired. And so on. In this sense, 'knowledge in practice' is always underway -the incorporation process cannot be viewed as an atomistic adding of elements to a never changing entity, but is in an essential manner a changing of the existing 'knowledge in practice' as well. This way of understanding 'knowledge in practice' of course raises the further question of how we ever come to have knowledge in the first place. If the acquisition of knowledge always presupposes a perspective, it seems impossible for us ever to get started. Alterna tively, is it possible to make sense of the suggestion that we are to some extent born with at least a limited perspective on the world? The answe r to this question lies, I think, in our bodily nature, and in the next section that concerns the role of the body, I shall try to expli cate in what way. Due to restrictions on the length of the paper, the explication will, however, be of a very tentative form.

The role of the body in knowledge acquisition

The point I wish to make in connection with the question of how we ever enter the (hermeneutic) circle of knowledge acquisition is that we do not come into the world as empty buckets waiting to be filled up -instead, as living bodies we have from the very beginning certain needs and wants that make some things matter more to us than others. This means that the world as we perceive it will be fore-structured -we are, so to speak, born with a perspective that makes the world a meaningful place in that it lets certain aspects of any given situation stand out as relevant and important (primarily aspects having to do with pleasure and pain, change and difference, and social responsiveness). This makes it possible for us to acquire some very basic and unsophisticated experiences that, in turn, are connected to the learning of certain very limited types of 'know how' and that are, as well, the bodily basis in relation to which language is later learned. Of course, this fore-structuring perspective is very far from being the 'knowledge in practice' described above -a much higher degree of sophistication in the aspects that present themselves is necessary for this -but still, it is a humble beginning that, give n time and participation in appropriate situations on the part of the individual, can evolve into the much more differentiated perspective of 'knowledge in practice'. Therefore, we are born, not with an innate 'knowledge in practice', but with the possibility of acquiring this kind of knowledge on the basis of our bodily fore-structuring of the world.

In this sense, the body can be said to form the starting point of human experiencing and knowledge. However, as I see it, the body also has more active roles to play in the actual acquisition of 'knowledge in practice'. For one thing, the tacit, experiential dimension of the meaning of our words and expressions, for which I argued above, is to a large degree made up of bodily sensations and feelings. The experience of being addicted to smoking, for example, though also involving a cultural aspect, e.g. pride in or shame at having this habit, definitely has a very important bodily ingredient -the feeling of 'having to have' a smoke -as well. In passing, it might be mentioned that the Wittgensteinian argument against a private language, or rather, the interpretations of the argument according to which feelings cannot be part of the meaning of our language since we would not be able to communicate about essentially private entities, to which no one else had access, in my opinion overlook the fact that our feelings etc. in a very important sense are not private: Our common human anatomy and physiology secures a sameness of experience at a very fundamental level, and actually, it is precisely this fundamental level of experience that gets language started in the first place. It is for example only because we all are hurt when we touch a hot stove that we react to the crying of the infant who has just put his hand on one by saying things like "ouch, that hurts!" We are here not describing a private entity to which only the infant has access -instead we are letting a feeling common to us all due to our common biology give experiential meaning to a word and in that sense letting it have a place in our language. All in all, therefore, at the level of the content of our experiences, the body is of very great importance for 'knowledge in practice'.

At another level, though still one related to the question of experience acquisition, namely the level of subsidiary experience, the body also seems to me to be of great significance. As I see it, the possibility of experiencing subsidiarily is to a great extent supplied by the body in that it upholds a kind of unfocused attentiveness to the situation while the mind focally is concentrated on only a part of it. This is the case in driving where one is focally mindful perhaps only of the cars ahead of one, but still has a bodily feel of the way the car moves and fits into the traffic, as well as an openness toward the situation as a whole by means of which one becomes aware of signs of a disturbing or dangerous incident about to take place. It is, I think, also the case when the medical practitioner has the feeling that 'something is wrong' with a patient, although he cannot 'figure out what it is', i.e. cannot 'get his mind focused on it' -here, too, his body seems to be serving as a kind of background awareness that lets him notice subsidiarily that of which he is focally unaware. Actually, I would contend that it can even be the case in the very theoretical field of physics where one, on being confronted with the results of someone else, can come to have a very bodily feeling ("a feeling in the guts", cf. [START_REF] Kanigel | Apprentice to Genius. The Making of a Scientific Dynasty[END_REF]) that something is not as it should be with the results, though at first it might not be at all apparent (i.e. in focus for the mind) what it is that is out of order. The body, therefore, at this level has a rather active role to play in the acquisition of 'knowledge in practice' in that it is a condition for the acquisition of a great many of our experiences.

Lastly, one might ask whether the body, in some instances at least, could be said actually to be the very subject (in the Continental sense of the word) of knowledge acquisition and not just to facilitate and structure the experiencing of the mind. It seems to me obvious that at least some of the experiences acquired subsidiarily will be acquired by the body, not by the mind, which is to say that we are not at all (mentally) aware of acquiring them. This will be the case for many of the experiences connected to bodily 'know how' -most people able to ride a bicycle, for example, have learned to do so without having been mentally aware of all the experiences facilitating the learning; a point that is reflected in the fact that, when asked in which direction to turn the handlebars when the bicycle is tilting to the left, they answer "to the right", even though what they actually do is turn them to the left (fortunately -otherwise they would fall all the faster…). Bodily 'know what' connected to 'know how' is, however, as I see it, not the only way in which the body can be said to be the subject of knowledge acquisition -one could give many examples of knowledge that, though once known to the mind, has been forgotten mentally and is only upheld by the body. One such example would be the knowledge of the code of a lock: People very often have the requisite knowledge 'only in the fingers and not in the head', i.e. they cannot say which digits the code has, but they can without any problems open the lock when standing in front of it. In this case, it seems reasonable to say that it is the body, not the mind, that is the knowing subject. All in all, I find that quite a lot of examples suggest that the body has a much more fundamental role to play in the acquisition and maintenance of knowledge than is normally ascribed to it. At the same time, I also think they indicate that the mind-body-distinction is not to be understood as designating a rigorous dichotomy, but rather as supplying a name for the two end poles of a continuity. Therefore, since the 'knowledge in practice' for which I have been arguing is essentially a tacit way of letting the world present itself to us as active, living, i.e. bodily, beings interacting with this world, it would seem to me that a further investigation into the concept of the body as a knowing subject and the relation between body and mind in this connection would be a particularly promising one to undertake. Actually, the perspective of 'knowledge in practice', given further analysis, might very well turn out to be to a great extent the perspective of the body.

Concluding remarks

In this paper I have argued that the knowledge we possess in practice is not, as traditional Anglo -American philosophy holds, exclusively, and not even primarily, linguistic knowledge, but instead has the form of a synthetic unity of the three aspects linguistic knowledge, practical knowledge, and experience. These three aspects, I have claimed, are ontologically speaking necessarily interrelated and can even for analytical purposes only be partially distinguished from one another. Within their unity, however, experience is the more fundamental one in that it supplies meaning to our words and expressions and gives the bodily 'feel of' necessary for practical knowledge. Their unity, which I have termed 'knowledge in practice', I have characterised as a perspective with which we in practice, i.e. as part of our way of living in the world, meet this world, whereby features of the concrete situation we are in come to stand out as relevant and important. Since a presentation of features as important, furthermore, is a prerequisite for experience acquisition as well as for the acquisition and structuring of linguistic and practical knowledge, I have contended that 'knowledge in practice' is necessary for the acquisition of its own aspects. The seeming contradiction involved in this statement, I have claimed, is resolved by the fact that 'knowledge in practice' is not a static entity, but an ever evolving phenomenon that develops from the very humble basis supplied by the fore-structure that our bodily being imposes on the world.

'Knowledge in practice', I have emphasised, is in an essential manner related to action in the world and therefore many of our experiences are acquired subsidiarily, without our being mentally aware of them, because our attention is focused on the goal of our activity. In relation to this kind of subsidiary experiencing our body has a large role to play, I have proposed, partly in supplying a background of unfocused attentiveness that lets relevant aspects not in the focus of our attention still be noticed, and partly in being the subject of the experience acquisition. As regards the last point, I have tentatively put forward the suggestion that the body might also in other respects be considered the subject of knowledge acquisition and maintenance and that actually the body has a much greater significance in the context of knowledge than it usually is accorded. In conclusion, I would therefore like to say that the relation between bodily being and 'knowledge in practice' remains a very exciting field of investigation -and one which I plan to delve into much more intensively in the future.