Whyte’s text reviews urban environments from a perspective of design. The methodology of the book is documentary, but it carries with it an agenda and exhortation for the enrichment of the spaces themselves. The purpose of designing spaces is to encourage the environment, urban life, and community. Having lived for the past several years in Atlanta, I find Whyte’s depiction of urban spaces to be somewhat shocking, a phenomenon that is easily supported by the fact that the book was published in 1980. It has been nearly 30 years since then, and the depictions of openness, freedom, and intermingled spaces have gradually been eclipsed by a number of factors. Our fear-loving political mentality among them. This outlook aside, and in spite of politics and our insular and slightly agoraphobic climate, much of Whyte has to say is extremely relevant from a number of perspectives.

Whyte is part of the “media traditions” tag on the big reading list. This is because the text is about urban planning and architecture. Much of what Whyte discusses are plazas, and how to design them to be inviting. This is relevant for anyone interested in architecture, but it is also relevant for anyone interested in social spaces, either real or virtual. From the perspective of AI and character simulation, it provides a useful glimpse into how characters might behave within certain spaces. Embodiment is a property of the situation as much as it is of the individual, giving some clues as to how to get characters to react to and experience spaces. Urban spaces are not especially interesting for my work, so I’ll focus on elements that may be more general.

The first thing to discuss is how Whyte might be used to discuss space within virtual worlds. Within multiplayer environments, this conveys the strongest analogue, but it may also be used to examine the relationship between the environment and simulated characters within first person games. The key goal of the book is the construction of inviting spaces. Whyte’s first main point is that it is people who determine the use of a space. All social spaces are emergent, and cannot be controlled directly. People will occupy places that are desirable, and will avoid places that are not. Paradoxically, what makes places desirable are other people. Plazas are expansive areas that are open for walking, and are usually placed outside of corporate buildings (in New York, the reason for this is also emergent, and relating to zoning laws that encouraged the development of plazas). This means that people move in and out of the plazas on their way to and from work, and often come outside around lunchtime. What makes these spaces appealing for use comes from several factors: sitting space, sunlight and shade, trees, water (especially waterfall features), food, retail, street performers, and ready access to the street itself. Aside from the environmental effects, these are all important because they are things that people will use. When a space is usable, and inviting to be used, it will be used. This is a sort of environmental sense of affordance.

Criticized in the book are “megastructures,” much like the hermetically sealed bubbles described by Jameson in Postmodernism. These are places with no readily visible or accessible ways in or out (on foot, anyway), and are built like fortresses. These structures are designed to be accessible primarily by car, and thus the visitors will be travelling from one bubble to another. Invariably, when present on the ground, these will have spiked ledges to disallow seating, and forbid any kind of casual use of the space.

A key takeaway in this is to consider the way that virtual spaces are designed, and assess whether they fall more into the category of the former or the latter. It is clear that spaces are the most lively when they are the most easily used. However, virtual space fits into this at an odd level. On one hand, virtual environments are not precisely necessary the same way that real ones are. Virtual bodies are not real, and the characteristic that makes spaces inviting, things such as: sitting area, food, proximity to important locations, such as the street, an office, or stores, are all essentially unnecessary in virtual worlds. These obstacles exist precisely because there are spaces that exist in between real people and where they are going. These simply do not exist in virtual space. A person using a computer does not need to go through a virtual space to procure food, or to sit down, or to shop, or to go to work. However, all of these processes may be simulated.

The situations where virtual places might be the most inviting are within multiplayer games, where the players have characters who inhabit these worlds and have things that they want to do in the world that are situated. The best example of this that I can think of is in World of Warcraft, specifically within the Horde city of Orgrimmar. There are three locations that players visit with great frequency: the mailbox, the auction house, and the bank. These three are conveniently placed very close to each other, creating a triangle of activity. Near that triangle may be found many players gathered together, occasionally talking, occasionally giving away enchantments, and occasionally dancing or behaving silly. Outside of hotspots like these, places are much less vibrant. In many games and virtual worlds, interaction with other players is done with private messages, which enables people to communicate without being near each other. Second Life enables instantaneous teleportation and flight, which is fun, but detracts from the necessity and integral nature of space. As a result, most spaces are empty, apart from the occasional drifters. By providing players with instantaneous access to the objects for which space is normally a medium, space becomes unnecessary, losing its value as a medium for emergence.

The key to getting an idea of “placeness” seems to be embodiment. We use space because we inhabit that space with our bodies. Virtual characters will use virtual space by inhabiting it with their own virtual bodies. One element to this is the simple necessity of being in a space. When the player (or a simulated character) is forced to occupy a space, that space will come to be seen in terms of affordances. Easy types of affordances are the relation of that space to other spaces. A reading room is a useful space because that is where the books are. However, other issues indicated by Whyte are important but very subtle. One is that people prefer to sit down. People also prefer to be in spaces that have consistent and pleasing climate (sufficient sun and shade). In games such as The Sims, these sorts of ideas are expressed by having sims have a “comfort” and “environment” needs. Playing a game of The Sims yields interesting emergent effects when the player furnishes a home. Frequently, the sims will coalesce and occupy one room more than the others, and that is generally the room that has the most comfortable furniture and the highest environment. I am not sure if this demands more attention, but it seems like it should be sufficient to simply be aware of that effect, and keep it in mind while developing models of how characters act within places.

Relating this to my work may take a bit of maneuvering, but it’s on my reading list, so here it goes.

Stoppard plays are often absurdist and existential, but come with a comedic vein absent in other absurdist theatre such as Beckett or Brecht. Rosencrantz and Guildenstern are Dead is set following the eponymous characters from Hamlet. While in Hamlet, Rosencrantz and Guildenstern are minor, spending most of their time in the background, in Stoppard’s play their roles are reversed with that of Hamlet’s cast. They exist in an ambiguous and indeterminate state, the very world around them is vague and indistinct. They are fraught with the problem of not being able to make out the world, and being unable to change their roles within it. The play reads like Hamlet’s backstage, only the actors never come out of character. The world seen is a quasi-state that is both part of Hamlet’s fiction and also is definitively outside of it.

This sort of situation is relevant to media studies from the perspective of its general philosophical influence, but also from the perspective of performance and presentation. Jay Bolter and Diane Gromala have described digital artifacts as being transparent and reflective. Transparency is the idea that a user may engage with a work without the interference of mediation. Reflective artifacts instead draw attention to the mediation and it is through that awareness that the work is able to convey meaning. Pure transparency is an illusion or myth, of course, as mediation is present in all interactions, and it is only through convention that these mediating factors are ignored, or understood symbolically without requiring contemplation.

Plays are artistic artifacts, which use mediating factors and devices which operate on a symbolic level that is meaningful to the audience. Conventions make use of the stage, especially in the way that characters enter and exit, to communicate symbolically to the audience what is taking place. A viewer unfamiliar with these conventions would not find plays to be transparent at all, and would be baffled by the characters who enter and exit, by the conventions of scenes, lighting, and curtains. They would be puzzled by these gestures much the same way that someone who had never seen a computer would be puzzled by a web browser. Beyond the pure issues in communication of symbolic gesture and representation, there is the issue of literacy. In addition to conventions of interpretation in a domain, there are also traditions of works and use which abide by and originate these conventions. A familiarity with these traditions is generally a form of literacy. When such conventions become pervasive enough to be naturalized, their use is considered transparent.

Reflective artifacts reveal that the mediation process still occurs, even in these circumstances. Absurdist theatre challenges the conventions of theatre and in doing so defamiliarizes the audience with the conventions and their expectations. Rosencranz and Guildenstern are Dead presents a view which operates in a liminal space between the domain of Hamlet and something else. It depends on the literacy of its audience to understand Hamlet, and also unseats the understanding and expectations regarding the nature of characters– how characters are supposed to work within a play in the first place. Characters are supposed to have clear identities (so we may identify with them), they are supposed to be empowered within the scope of the action (so we may admire them), and they are supposed to be naturally within the world (so the world will seem real to us).

Stoppard’s play is also significant from the perspective of literary extension and adaptation. Rosencrantz and Guildenstern are Dead extends the world of Hamlet. This is important because of the form of the adaptation. The play extends the characters of Rosencrantz and Guildenstern, but also borrows some of the major cast of Hamlet. The borrowed characters are not extended, are not presented as whole round characters, but are rather flat representations. We understand the significance of Hamlet not because of what he does, but because we know that he’s the same Hamlet from Shakespeare’s play. The world of Shakespeare’s Hamlet is evoked, but not extended or even represented. The result is something which produces a commentary on the original material. Instead of continuing the world of Hamlet with its own rules and logic, we see the events of Hamlet rendered according to a new set of rules. In essence, the representation has not changed, the key events have not changed, but the underlying model that produces those events has changed.

Saussure is one of the establishing figures in modern linguistics and semiotics. Saussure’s work is important because it establishes the origin of structuralism in linguistics. The theory of language is important in any investigation of media studies, and the ideas of communication and signification are especially relevant in the perspective of networked discourse and visual culture. However, my approach is going to be to look at Saussure from the perspective of meaning and symbolic systems. Structuralism seems a certain starting point for the logic of traditional AI, but Saussure’s conception encourages thinking much more broadly: he discusses the perception of language both as a fixed system (synchronic linguistics), as well as a system that evolves in time (diachronic linguistics). Both of these depend on a community of speakers to share the meaning of signs. I will focus on the sections of general principles and synchronic linguistics.

Part I: General Principles

Saussure opens by contextualizing his goal in opposition to the existing view of language, which is that words correspond directly to meanings. Instead, he claims that concepts are tied to “sound-images.” This connection is psychological and not associative. The pair of the concept and sound-image is a sign. The sound-image is the signifier, and the concept is the signified. Signs operate according to two principles: Arbitrariness and linearity. Signs are arbitrary because, in terms of words, there is nothing in the signifier alone that naturally implies the signified, and it could easily be any other signifier that could be bound to the signified. The claim of arbitrariness is slightly contestable given recent studies in cognitive science, but for the most part, it is logically sound. Saussure does discuss later how elements of words (prefixes and postfixes that can be tied to other word bases) are signifiers in of themselves. Linearity applies to the fact that we perceive signs, read and hear, linearly. This has to do with our inherent means of perception and ability to read and interpret language.

Language has qualities of both immutability and mutability. Language is immutable in the sense that it is intangible and connot be consciously changed by a single speaker. A speaker who wished to change language would not be able communicate the changes with others by simpy using the changes. Language instead depends on a community of speakers, who use the language through time. The key dimension in this is time. Without movement in time, a language has the potential for life, but it does not live. Through time, the language will suffer inevitable changes. It is productive to think of this at a meta level, in terms of Barthes’ mythologies, and look at texts and readers. Texts too have a life in time, and are interpreted differently over the course of it.

Part II: Synchronic Linguistics

This section is on synchronic linguistics, which is linguistics that have a fixed state and does not change over time. This can also be read as a general interpretation of language meaning and use.  Saussure argues that linguistic entities are concrete, if and only if it has both an expression and meaning. The meaning of an entity may also be considered an intention or representation). Entities must be delimited via difference from, and as separated from other units. The idea is that a linguistic expression (like a word or a phrase or a sentence) is composed of units, such as words or syllables, and these syllables must be delimited from each other, and distinguished by their difference to other units.

Thought and sound are coupled in the understanding of language. This is at outset a troubling argument, as the deaf can use language, but Saussure might refer to images or muscle patterns to account for this case. The argument seems to go in the direction that a union of perception and expression comprises thought. “Linguistics then works in the borderland where the elements of sound and thought combine; their combination produces a form, not a substance.” (p. 113; emphasis in original) Saussure’s goal is to understand the idea of linguistic value, but value differs from signification. This is because signification involves a certain multiplicity, whereas value does not.

There is a paradox in seeing the sign or word-meaning as a linguistic unit, as it is interdependent. Language as used contains interdependent terms, and the spoken word does not stand on its own, but depends on the words around it. Note that GOFAI symbols are independent/universal/objective. There are two elements to linguistic values: (1) Dissimilar things can be exchanged for the thing of which the value is to be determined. (2) Similar things may be compared with the thing of which the value is to be determined. The essence of these are similarity and exchange. These are the core of the process of transformation. Transformation occurs between signs and reality, as well as between sign systems. Values may be exchanged, but signified may not exactly be exchanged. Saussure gives the example of the English word “sheep” and the French word “mouton,” both of which signify a sheep, but they do not have the same value. The French word “mouton” also signifies the food for which the English word is “mutton.”

Language ultimately comes down to differences. The key element is distinction between elements such as letters and phonemes. Differences are within the system, not before it. Both the signified and signifier exist differentially, in that they are different from other signifieds and signifiers, but the sign as a whole is a positive unit.

A syntagm is framed as a meaningful connection between two linguistic terms. These are structures within the system. Extra-system comparisons form associations, which are formed in absentia, whereas syntagmatic relations are formed in praesentia. A syntagm is two terms effective in a series. Saususre gives an example of a building supported by columns. The relation between the base, column, and roof are syntagmatic relations, whereas the type of column that may be present (Doric, Ionic, Corinthian, etc) are associate relations. The syntagm is a role and position within space or time, and an associative relation is the capacity for variance and multiple values. (I think the term for this has been co-opted as a paradigmatic relation.) Terms and meanings are built from syntagmatic and associative relations. Associative relations work via difference, but syntagmatic relations are constructive.

It is difficult to write a summary for a dictionary. So, a bit on the context: Gerald Prince developed this as a dictionary of important terms in the study of narrative. Because narratology takes into account many perspectives and has deliberate uses and definitions of terms from normal English, a dictionary is worthwhile in both expounding those terms and contextualizing their theoretical underpinnings. This is a useful source for referencing in pursuit of clear explanation for terms and to find the scholars who popularized their use.

Instead of organizing my discusion into sections, I’ll instead pull out several terms which are relevant for my work, and paraphrase Prince’s take on them.

Actant: An actant is a role in narrative deep structure. This is useful for the structural analysis of narrative, and in this context forms a kind of syntactic unit. It is important to note that an actant is a role, not a character. An actor is a concretized actant, one who occupies the actant role. The actant fits into the “actantial model,” which operates like a narrative version of semiotic communication theory. The actant roles in this model are Sender, Subject, Helper, Object, Opponent, and Receiver. This was primarily developed by Greimas.

Character: One definition is that a character is simply “an existent endowed with anthropomorphic traits and engaged in anthropomorphic actions; an actor with anthropmorphic attributes.” (p. 12) Or alternately, “an actor; an existent engaged in an action.” (p. 12) Characters are classified in terms of flatness and roundness, as well as the spheres of action they reside in, the roles or actants they occoupy or concretize.

Deep Structure is the lowest level of structure, which is in opposition to the surface structure. This defines the meaning of the narrative. The relationship between actants occurs at the level of deep structure, while actors and characters operate at the surface level. The deep structure cooresponds to story, wereas the surface structure corresponds to discourse. In the Greimassian model, the deep structure can be converted into the surface structure by means of transformations.

Diectic is used as a literary term, indicating situating prepositions and adverbs. Diectic terms situate the characters in the diegetic time.

Diegesis: “The (fictional) world in which the situations and events narrated occur.” (p. 20) This is another way of referring to the story world. Normally it is considered in terms of the diegetic level, which can have interdiegetic and extradiegetic dimensions.

Discourse is the expressive part of a narrative, in opposition to the content part. Discourse defines how the story takes place, as opposed to what takes place. Frequently, discourse is used to describe discussion and rhetoric within a conceptual domain, but the definition here is centered on the expression of a narrative alone.

Function: An act which is significant in terms of the narrative action or situation. The strongest use of function comes from Propp. Barthes describes a function as a narrative unit which is related to the others metonymically. That is, the function is related to the situation through consequence (or causality). The function is opposed to the index, which supports the narrative metaphorically. The idea is that the function supports the events, but the index supports the atmosphere.

Narrative Domain: This is defined as the space of possible outcomes within a situation inside of a narrative, or the set of possible moves or functions which charactes may perform. “From a schematic point of view, a narrative domain is governed by a number of maxims or rules establishing what is or could be the case, regulating the character’s knowledge, setting his or her priorities, and, most generally, guiding him or her in assessing a situation and reacting to it.” (p. 62) This seems to represent the idea of the possible generative outcomes of narrative systems.

Narrative World: A set of motifs in a narrative which are considered true and factual within the world. Ryan (1985) distinguishes between actual and possible worlds. My understanding of narrative worlds is much more specific, and covers the cognitive and conceptual dimensions of the world as defined by the author and reader.

Possible World is a sset of affairs and individuals which is complete for a particular narrative. This is defined in terms of what is considered factual in context of a narrative, but also what is non-actual, given by character’s plans, beliefs, or fantasies. The definition as given considers possibility in terms of possible interpretations or ambiguity (Eco style openness), but not genuine possible variance of the course of narrative events.

Schema: A semantic framework which represents the perception and comprehension of reality. Schemata are serially oriented, and work with other cognitive elements, such as plans, frames, and scripts. A plan is considered a goal-oriented schema. Whereas frames are parallel modes of perception and interpretation. Scripts are explained to be interactive schemata intended for situational use, “sterotypical, goal-directed schemata” (p. 86)

This book is primarily pratice oriented, aimed at those who wish to practice game design. The goal is go develop a psychological understanding of game characters. The emphasis on psychology comes in opposition to the method of designing game characters based on cinema and other passive and linear media. Because games are interactive, players interpret characters in richer ways, so a perspective anchored on social psychology is much more apporpiate.

Part I: First Impressions

The early discussion covers visual cues that affect the player’s creception to characters. The qualities that are explored are: attractiveness, baby face, and stereotypes. This is not about social roles yet, but about presentation and expression, which may or may not relate to player expectations. When player expectations are fulfilled, this creates a smooth and consistent experience, but when expectations are broken this can be surprising or confusing to the player. Broken expectations can lead to depth of experience, but if not done properly, the effect can simply be jarring.

This first section is on personality traits which are expressed by characters. These are studied with respect to the building of first impressions. The most important personality traits discussed are dominance and agreeableness. Characters can express dominance through pose and demeanor. Generally, player characters are expected to be dominant to some degree. Isbister cites Maslow’s hierarchy of needs as an example for how to think about how a player will react to other characters. Because safety is one of the more fundamental needs, dominance and agreeableness are the first elements of character that are read by the player. Dominance also resembles the idea of “status” that is derived from Johnstone’s Impro. Dominance and agreeableness may be seen in a spectrum relative to the player character. The attributes are relational, not absolute. Changes in agreeableness and dominance are evidence of significant changes, or are expressions of communicative symbols.

In addition to dominance and agreeableness, Isbister explains that there are five common personality traits that are common across cultures (pulling from McCrae and Costa). These are denoted by the acronym OCEAN, for Openness, Conscientiousness, Extroversion (dominance), Agreeableness, and Neuroticism.

Part II: Focus on the Player

The first section covers culture, from the perspective of design. Design is relevant from the perspective of the audience in terms of how culture is portrayed. The section is primarily oriented around thinking about the culture of the player, and seems to have an underlying goal of teaching designers how to think about culture for games that are going to be marketed in cultures different from the designers’ own. My interest extends beyond this a bit, thinking about cultural representations for characters, as opposed to the cultural world of the player.

Cultural differences are described in terms of:

1. Expressions and physical characteristics. Gestures and expressions have different values across cultures. This category affects the reception of signals cast in body, face, voice, touch, and social distance.
2. Social norms and expectations. Roles and expectations of the individual vary among cultures. For example, American culture has a strong ideology that everyone must fend for themselves, whereas within Japanese culture there is an expectation of interdependence. Roles have much to do with games because of the role of the player and the corresponding hero archetypes.
3. Local media contexts. When marketing to other cultures, one must be aware of the media contexts and traditions there. This suggests consideration of the cultural “grand” narratives which have formal and structural characteristics, in addition to ideology.

Isbister describes gender, but again from the perspective of thinking about the player. The discussion is aimed to encourage designers to think beyond the andronormative perspective that tends to plague the game industry. Gender is the element of sex that is learned in culture, not inherited. It is culturally defined and time dependent, variable, and constantly changing. Discussion describes 3 bullet points aimed at thinking about gender in design.

1. Play style: what girls like to do in games versus boys. This is an open topic, but has had much research. Isbister lists several findings (p. 112):
   • Girls tend to enjoy games that allow for open-ended play and exploration that does not necessarily require completion of one goal or level to get to the next (Gorriz and Medina 2000, Kafai 1996).
   • Girls play games with puzzles or mysteries over games that involve physical accuracy and acuity (Children Now 2001, Gorriz and Medina 2000).
   • Girls would rather spend their time creating things instead of destroying things (Gorrriz and Medina 2000, Bruner, Bennet, and Honey 1998).
   • Girls enjoy everyday life activities and metaphors just as much if not more than fantasy adventures (Subrahmanyam and Greenfield 1998).
   • Girls may be less comfortable than boys about just jumping in and exploring a game to learn how to do things; they may do better with more explicit mentoring and instruction at the beginning of a game (Subrahmanyam and Greenfield 1998).

   There is furthermore another set of bullets that discusses how girls relate to others (whether players or NPCs): (p. 114)

   • Girls prefer collaboration to violence against others in games (Gorriz and Medina 2000, Subrahmanyam and Greenfield 1998).
   • Girls tend to prefer working in smaller teams than boys do (Subrahmanyam and Greenfield 1998).
   • Girls enjoy forging relationships–visiting other characters, writing letters, learning about how other characters feel about what is going on (Subrahmanyam and Greenfield 1998, Greenfield, Bruner, Bennet, and Honey 1998).
   • Girls are interested in the story behind the story–motivations and interrelationships among characters (Gorriz and Medina 2000).
   • Girls enjoy communication with other girls, and games that encourage or incorporate chat and social activity in conjunction with the game can support this (Gorriz and Medina 2000).
2. Roles: comfort and fantasy. The essence of discussion on roles is to include a variety of roles for female characters. It is important to have a variety of gender roles that the player may explore and relate to.
3. Expectations: what is expected in interactions. It is important to have gender aware reactions, and especially not get it wrong. Having characters treat the player with the expectation that she is male is alienating and dissociative. Gender plays a strong role in everyday life reactions, and to ignore the differences in these reactions tends to encourage the expectation that the player is always male.

Part III: Using a Character’s Social Equipment

This part covers the means of expression of a character’s emotion, intention, and personality. The subsections are the face, the body, and the voice. I do not go over this last section in detail, but the first two are fairly relevant, especially from the perspective of simulation and embodiment.

The face is very important for psychological understanding, and the muscles and expressions that act in the face can be divided into action units (Eckman, Freisen, and Hagen 2002).  Isbister also discusses the four basic emotion types, which are so considered basic because they are universally recognized across cultures and share common physical expressions in the face. These are anger, fear, happiness, and sadness. The gaze is also read in the face, and the gaze can also have functional properties. One’s face is an expressive object which can convey emotion and personal state. Finally, faces are tied to emotional feedback, and this produces mimicry. Here are some bullet points that address the communicative symbols of the gaze: (p. 145-146)

• Dominance or submissiveness (patters of holding or avoiding direct eye contact)
• Where a person’s attention is at the moment
• Flirtation
• Interest in beginning a conversation (or desire to avoid one)
• An invitation for one’s conversation partner to take a turn in the dialogue
• Active listening
• Pondering of a point

Body language may be used in character design. Body language is an expression of embodiment, so describing body language formally and developing a symbolic language for the body is a productive goal. Isbister divides body languagee into four categories: distance, touch, imitation, and posture. The first element of body language is distance, how far people stand from each other. There are four types of distance:

1. Public distance (more than 12 feet)
2. Social distance (12-4 feet)
3. Personal distance (4 feet to 18 inches)
4. Intimate distance (less than 18 inches)

Touch falls into four functional categories. An interesting thing is that these are used fairly effectively within, for instance, The Sims. These are again culturally dependent, and will operate differently in modern America, versus modern Japan, or Regency England.

1. Function (a doctor’s examination, or having one’s coat removed by a servant)
2. Social ritual (a handshake)
3. Friendship building (friendly hug or a pat on the shoulder)
4. Intimacy (sexual interest or emotional connection)

Imitation is the quality of imitating someone’s posture or gestures. This occurs most frequently when the imatated person is more dominant, the rest of the group will mimic his or her behavior. Conversation also produces mimicry among its participants. Posture is very rich for expressive signification. Isbister references Gallaher (1992) to isolate four categories of posture. These correspond strongly with the dominance and agreeableness dimensions, and they also are affected by culture and gender.

1. Expressiveness (variety and energy in expressions)
2. Animation (energy in movement)
3. Expansiveness (occupation of space) — this is most strongly aligned with dominant personalities.
4. Coordination (smooth movement and grace)

Part IV: Characters in Action

The first section in this part discusses player psychology, and the types of engagement the player has with the game world. This relates to thinking of player character design as an extension of the player. Isbister outlines four categories of experience. These can be aligned with the player expectations, and to do so produces coherent and smooth gameplay.

1. Viseral is the sense of being in the world and having augmented engagement. Visceral experience in games is usually the type of experience that the player would not be able to do in real life.
2. Cognitive is the way that we map our own problem solving onto the character. When our plans map easily onto the abilities of the character, the expierience is smooth.
3. Social is the element of interpreting others socially, and enables the player to wear personal masks.
4. Fantasy is the capacity and appealingness of exploring new identities within the game world.

There are three types of player characters according to Isbister: tools (no PC), puppets, and masks. I think there are hybrids in this mapping. Puppet characters are like characters in platform games, where the character has a distinct identity, and expresses that identity through its behavior in the world. Masks are commonly used in MMOGs, where the player is given rich tools for customization and for performance of the character, especially via emotive expressions. This last category though gets ambiguous with first person games, and games like Fallout 3, which have a lot of mask like qualities (customization, decision making), but few elements of performance.

Discussing NPCs, Isbister uses the language of roles. Role awareness is important in interaction, and consistent role views and expectations create smooth experiences. Misunderstanding of roles will lead to trouble (both socially and within games). This can be productive (when one wishes to create tension), or simply jarring for the player. There are three elements to roles, which are interdependence, power dynamics, and obligations and investment. Interdependence is the objective and ability of the NPC. Even hostile NPCs provide interdependence by providing opposition and conflict for the player. Isbister reviews many common NPC types and discusses them all in light of these three categories, as well as by the defining manner in which they interact with the player.