Crimes Against Mimesis, Part 3

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Roger Giner-Sorolla

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Apr 25, 1996, 3:00:00 AM4/25/96
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5. "I Am Not A Puzzle! I Am A Human Being!" -- The Reality of NPC's

Paper-and-pencil roleplaying games use the term "non-player characters",
or NPC's, to refer to the troupe of imaginary personalities controlled by
the game referee. In the hands of an imaginative referee with a flair for
improv acting, NPC's can take on a life of their own. The referee can
assess how they would react in nearly any situation, and have them banter,
barter, bluster or battle accordingly, pursuing their own motivations
while remaining true to type.

Computer interactive-fiction games also refer to characters programmed by
the game's author as "NPC's". In a comparison between the two kinds of
game, though, the live referee has a rather unfair advantage over the
programmer. The game-master bases NPC output on a highly sophisticated
interactive algorithm synthesizing years of social observation and
literary convention: the human mind. To even begin to compete, the
computer-game author must effectively write this algorithm from scratch;
an impossible task, even for the artificial-intelligence experts!

With limitations like this, it's hard to blame game designers for
following the lead of the early text-adventure games, and relegating NPC's
to very simple roles: either roving menaces from a hack-and-slash campaign
of Dungeons and Dragons (the dwarf and pirate in Adventure, the thief in
Zork) or mere components of a lock-and-key puzzle (the troll and bear in
Adventure, the cyclops in Zork). And yet, a few game designers have
managed to create memorable and personable characters. In the Infocom
era, the robot companion Floyd from Planetfall stands out. Among recent
games, Jigsaw is notable for the enigmatic and recurrent character Black,
while Christminster employs a dramatis personae of no fewer than twelve
vivid personalities, including a very stubborn cat.

Amazingly, when examined closely, memorable characters in IF are really
doing much the same things that their more forgettable counterparts are
doing -- roaming about the map, reacting to single words, serving as
puzzles to be overcome by the right object or objects to overcome the
right puzzle. Few works of linear fiction can entirely dispense with
non-protagonist characters; even Jack London's classic solo adventure
story, "To Build A Fire", included a canine character with at least as
much personality as the hapless human hero. So, if our goal is to write
IF that is good fiction as well as a good game, it's essential to make
characters come alive -- preferably, without resorting to advanced
artifical intelligence programming!

Good writing, of course, is the linear fiction writer's key to creating
believable characters without any interactivity at all, and the text
elements of the interactive NPC -- description, dialogue and actions --
are no different from those of the fictional character. The challenge is
in joining these elements into a single, well-defined character. As with
object placement, there are many ways to achieve the illusion of realism.
An NPC's features need not be completely expected and stereotypical, but
they should be explained if they violate common sense, unless you're
aiming for a comical effect. Why is the policeman cowardly? (His uncle is
a big political boss who got him the job.) Why does the minister take your
satchel? (He believes you are an immoral thief and intends to return your
treasures to their rightful owners.)

In fact, all the characters in a game, even minor ones, should be able to
pass the book editor's eternal question, "What *motivates* the dwarf to
throw an axe at you?" The ticket-taker takes your ticket because it's his
job; a desire for world domination pushes Sauron to seek the One Ring; and
so on. The answer need not be terribly deep, but it should be evident
from the context and the information you provide.

Continuity across settings helps immensely in convincing the player that
an NPC exists independently of any single puzzle. A single character who
appears in a variety of situations (like Planetfall's Floyd) offers far
more opportunity for character exposition and development than would an
arkload of different creatures, one for each puzzle. As with objects,
well-developed NPC's should have more than one function in the game, and
these functions should make sense as a whole given the NPC's personality
and motivation. In Christminster, Professor Wilderspin's erudition,
kindness, and love of exploration are very consistently brought out
through the puzzles in which he figures, and the result is an interesting
and emotionally engaging character.

A more complicated example of continuity appears in Jigsaw, where the
character of Black starts out as an impossible yet oddly helpful
annoyance, and gradually reveals playful, vulnerable, and even amorous
sides over the course of sixteen episodes. Perhaps only love can explain
why Black allows the protagonist to interfere, time and time again,
with his/her attempts to change history! In any case, the development of
Black's character across such a variety of roles is an impressive feat. If
it works, it does so because of the multifaceted personality and
conflicted motives that are brought out in Black's reactions and dialogue
-- continuity through an explicit admission of discontinuity, perhaps.

The beauty of the NPC illusion is that, when well-done, it can hide
enormous limitations in the interactivity of the character. Inform and
TADS only allow the player to converse after a fashion, by probing the NPC
with single-word input ("ask Einstein about relativity"). Even with this
limitation, it's patently unrealistic to expect a piece of code to be able
to hold forth about every irrelevant topic the player could bring up. At
the very least, though, a well-developed NPC should be able to react to
basic conversational input about the elements of the present situation,
and about his/her background. The default response for unknown input can
itself convey character; consider "Fiona treats you to a lengthy and
brilliant conversation about <topic>, which unfortunately leaves you no
closer to getting out of the prison cell" versus "Fiona just
grunts and goes back to reading her paper". Customized responses to social
actions such as "kiss","hit", and "give" are also essential to the
fully individualized NPC.

Are there workable models for more complex and responsive NPC's? While
it's unreasonable to expect an intelligence like 2001's HAL to emerge from
a 400 kilobyte game, I think that the increasing desire of authors to
create interactive games with literary elements may result in games where
the NPC, instead of being a mere accessory to a lock-and-key puzzle
("Hercules, lift stone"; "give mouse to cat"), actually is the puzzle.

I have in mind a very interesting class of NPC created on DhalgrenMOO by
the character "Calkins." (Those with Telnet access may log on to Dhalgren
at dhalgren.english.uwashington.edu 7777, then "connect Guest" and "help
#192" to see more information on this NPC class.) Essentially, this
type of automaton is a psychological maze. The rooms are the NPC's moods,
such as "angry" and "interested", and the passages are the player's
commands such as "hug NPC","feed NPC" and "ignore NPC". The automaton's
description changes with its mood, and each command is echoed by a
response, which may or may not help the player figure out exactly what
impact the command has had.

As a specific example, allow me to present my own creation, the automaton
"Kim" (currently on display at DhalgrenMOO; type "@go #1603" to join her).
This is a transcript of one of many possible interactions with her; the
command and response syntax should be familiar to adventure-game players.
"Trismegistos" is my character; the automaton's responses are displayed to
all players in the room (including the person interacting with it) in the
third person, which makes for some inconsistencies in grammar.

look at kim {initial description}
A short, craggy, thirtyish shag-cut blonde, wearing black Keds and a
sleeveless blue greasemonkey coverall with her name stitched above the
ciggy pocket. Kinda tough, kinda tender, she could be your best buddy or
your worst nightmare.

smile kim
Trismegistos catches Kim's attention by trying to smile. She smiles right
back at Trismegistos, half-mockingly.

l at kim {description for new mood}
Kim looks back at you, half amused. She seems relaxed.

talk kim
Trismegistos's conversation interests Kim. She crosses her arms and smiles at
Trismegistos, listening.

l at kim
Kim smiles at you. "Whatcha lookin' at?"

sing kim
Trismegistos sings, and Kim sings along, loudly and off-key, smiling.

l at kim
Kim smiles at you. "Whatcha lookin' at?"

talk kim
Trismegistos's conversation grabs Kim. She listens, smiling, and laughs
at all Trismegistos's jokes.

hit kim
Trismegistos hits Kim, who hits him back, playfully.

kiss kim
Trismegistos's kiss cools Kim down some. She looks at Trismegistos warily,
trying to figure him out.

l at kim {back to initial}
A short, craggy, thirtyish shag-cut blonde, wearing black Keds and a sleeveless
blue greasemonkey coverall with her name stitched above the ciggy pocket.
Kinda tough, kinda tender, she could be your best buddy or your worst
nightmare.

Note that the same command can have different effects, depending on
which mood she's in. (I wouldn't advise hitting her when she's not in a
good mood!) Note also that these are only three of her eight moods.

Characters with "mood mazes" have many possible uses in a game. Some
moods may provide vital information; other moods may make the character
more receptive to requests for help. Moods might also be triggered by
giving or showing certain objects to the NPC, or asking her about certain
things, or bringing other NPC's into the room ... The possibilities for
creating intricate social situations are nearly endless.

I can't help but suspect that character-based puzzles may have taken on a
stigma from early attempts like the seduction puzzles in "Softporn."
(Yes, Kim can also be seduced; but the direct approach won't work, and the
actual experience may be less fun than getting there...) This stigma is
unfortunate, because pornography is not the only fictional genre that can
be adapted into an IF game via social and psychological, rather than
physical, problem-solving. Imagine games centered on courtly intrigues,
political maneuvering, or the machinations of the psychological thriller!
Concepts like "Dangerous Liaisons: An Interactive Intrigue" could go a
long way to attract players who are put off by conventional,
scavenger-hunt type puzzles, and want a more literary experience.

[Coming next: The player's character in IF, and the game itself]

Roger Giner-Sorolla New York University gi...@xp.psych.nyu.edu
~~~~~~~~~~~~~~~~~~~ Department of Psychology ~~~~~~~~~~~~~~~~~~~~~
~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
"Sur l'oreiller du mal c'est Satan Trismegiste
qui berce longuement notre esprit enchante' ..." -- Baudelaire

bl...@ibm.net

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Apr 26, 1996, 3:00:00 AM4/26/96
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In <Pine.SUN.3.91.960423...@xp.psych.nyu.edu>, Roger Giner-Sorolla <gi...@xp.psych.nyu.edu> writes:

(This entire series of posts is excellent, by the way. I hope somebody's
saving it.)

>
> 5. "I Am Not A Puzzle! I Am A Human Being!" -- The Reality of NPC's
>

> Characters with "mood mazes" have many possible uses in a game. Some
>moods may provide vital information; other moods may make the character
>more receptive to requests for help. Moods might also be triggered by
>giving or showing certain objects to the NPC, or asking her about certain
>things, or bringing other NPC's into the room ... The possibilities for
>creating intricate social situations are nearly endless.
>
> I can't help but suspect that character-based puzzles may have taken on a
>stigma from early attempts like the seduction puzzles in "Softporn."
>(Yes, Kim can also be seduced; but the direct approach won't work, and the
>actual experience may be less fun than getting there...) This stigma is
>unfortunate, because pornography is not the only fictional genre that can
>be adapted into an IF game via social and psychological, rather than
>physical, problem-solving. Imagine games centered on courtly intrigues,
>political maneuvering, or the machinations of the psychological thriller!
>Concepts like "Dangerous Liaisons: An Interactive Intrigue" could go a
>long way to attract players who are put off by conventional,
>scavenger-hunt type puzzles, and want a more literary experience.
>
>

>Roger Giner-Sorolla New York University gi...@xp.psych.nyu.edu
>~~~~~~~~~~~~~~~~~~~ Department of Psychology ~~~~~~~~~~~~~~~~~~~~~
>~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~

I've been thinking along these lines myself recently. If the game I'm working
on ever gets past the early design stage, it's going to have several NPCs with
variable emotional states which can be affected by the player's actions and
conversation. If I'm feeling really ambitious, there might even be "emotional
fallout" between the NPCs. (For example, if the player gets Mr. Brown really
angry, he may have an "offscreen" tiff with Mrs. Brown, who will be sulking
and uncooperative when the player next meets her.)

Currently, I'm leaning toward the idea of adding some conversational verbs to
the standard "Ask about ..." and "Tell about ...". "Insult Roger" "Flatter
Linda" "Argue with Dobson", that sort of thing.


======
Steven Howard
bl...@ibm.net

Jorn Barger

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Apr 28, 1996, 3:00:00 AM4/28/96
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[ This is from a thread on rec.arts.int-fiction, where they try to
make better text adventure games (eg Zork) by making better
simulated characters (NPCs). I'm xposting to sci.psychology.theory
and sci.cognitive where people have been discussing emotion.]

In article <Pine.SUN.3.91.960423...@xp.psych.nyu.edu>,
Roger Giner-Sorolla <gi...@xp.psych.nyu.edu> wrote:
[...]


> I have in mind a very interesting class of NPC created on DhalgrenMOO by
>the character "Calkins." (Those with Telnet access may log on to Dhalgren
>at dhalgren.english.uwashington.edu 7777, then "connect Guest" and "help
>#192" to see more information on this NPC class.) Essentially, this
>type of automaton is a psychological maze. The rooms are the NPC's moods,
>such as "angry" and "interested",

That _is_ very interesting! So, each character has a fixed number of
moods (what are they?)... but these are just metaphorical 'rooms', of
course-- you still have to have regular space... surely?

> and the passages are the player's
>commands such as "hug NPC","feed NPC" and "ignore NPC".

So you have a deterministic 'state table', and verbs that always lead
from any given room to a specific second room...?

And a personality is defined mostly by this table (plus the fixed text
descriptions of each state and passage)... so you might have different
tables for different personality types... but most people will probably
share the same basic table...

> The automaton's
>description changes with its mood, and each command is echoed by a
>response, which may or may not help the player figure out exactly what
>impact the command has had.

For those of us too lazy to do the research, will you spell out the
table Kim uses?

> As a specific example, allow me to present my own creation, the automaton
>"Kim" (currently on display at DhalgrenMOO; type "@go #1603" to join her).
>This is a transcript of one of many possible interactions with her; the
>command and response syntax should be familiar to adventure-game players.
>"Trismegistos" is my character; the automaton's responses are displayed to
>all players in the room (including the person interacting with it) in the
>third person, which makes for some inconsistencies in grammar.

If you've got multiple people, then they're all somehow participating
in two forms of 'space' at once-- the ordinary one, plus Kim's
emotional space?

>look at kim {initial description}
>A short, craggy, thirtyish shag-cut blonde, wearing black Keds and a
> sleeveless blue greasemonkey coverall with her name stitched above the
> ciggy pocket. Kinda tough, kinda tender, she could be your best buddy or
> your worst nightmare.
>
>smile kim
>Trismegistos catches Kim's attention by trying to smile. She smiles right
> back at Trismegistos, half-mockingly.

You mentioned a mood called 'interested'-- I assume we're there now?

>l at kim {description for new mood}
>Kim looks back at you, half amused. She seems relaxed.
>
>talk kim
>Trismegistos's conversation interests Kim. She crosses her arms and smiles at
> Trismegistos, listening.

Oops-- this must be interested, so the last room was un-interested?

>l at kim
>Kim smiles at you. "Whatcha lookin' at?"
>
>sing kim
>Trismegistos sings, and Kim sings along, loudly and off-key, smiling.
>
>l at kim
>Kim smiles at you. "Whatcha lookin' at?"

Does singing not lead out of 'interested', then?

>talk kim
>Trismegistos's conversation grabs Kim. She listens, smiling, and laughs
> at all Trismegistos's jokes.
>
>hit kim
>Trismegistos hits Kim, who hits him back, playfully.

Now, if this verb leads back to the same room, that means that no
matter how many times you repeat it, it will never change-- a limitiation
of fixed state-tables.

>kiss kim
>Trismegistos's kiss cools Kim down some. She looks at Trismegistos warily,
> trying to figure him out.

Now, here you have to embody a theory of seduction-- and I wonder how
possible this is with a small finite number of deterministic states?

>l at kim {back to initial}
>A short, craggy, thirtyish shag-cut blonde, wearing black Keds and a sleeveless
> blue greasemonkey coverall with her name stitched above the ciggy pocket.
> Kinda tough, kinda tender, she could be your best buddy or your worst
> nightmare.
>
> Note that the same command can have different effects, depending on
>which mood she's in. (I wouldn't advise hitting her when she's not in a
>good mood!) Note also that these are only three of her eight moods.

uninterested, interested, and... wary?

> Characters with "mood mazes" have many possible uses in a game. Some
>moods may provide vital information; other moods may make the character
>more receptive to requests for help. Moods might also be triggered by
>giving or showing certain objects to the NPC, or asking her about certain
>things, or bringing other NPC's into the room ... The possibilities for
>creating intricate social situations are nearly endless.

As soon as you start including other forms of 'memory' besides 'room
memory', though, I think you lose the real value of the metaphor.

What I like about this *experiment* is that it offers an interesting
***but very limited*** palette of possibilities to explore. As soon as
you add variables that can 'remember' past states, you're betraying the
simplicity of the metaphor-- after all, the moods themselves could
have been implemented as variables...

> I can't help but suspect that character-based puzzles may have taken on a
>stigma from early attempts like the seduction puzzles in "Softporn."

Remind me how these worked...?

>(Yes, Kim can also be seduced; but the direct approach won't work, and the
>actual experience may be less fun than getting there...) This stigma is
>unfortunate, because pornography is not the only fictional genre that can
>be adapted into an IF game via social and psychological, rather than
>physical, problem-solving. Imagine games centered on courtly intrigues,
>political maneuvering, or the machinations of the psychological thriller!
>Concepts like "Dangerous Liaisons: An Interactive Intrigue" could go a
>long way to attract players who are put off by conventional,
>scavenger-hunt type puzzles, and want a more literary experience.

I've been meaning to repost the interactive-romance thread from 1993--
I think it predates the archive. My view of modelling romance *or*
seduction is that it requires *levels of permitted-access*-- you have
to respect the proprieties at each level to earn access to the next
(with special interesting exceptions).

I suggested a control-dimension of warm-response/cool-response that
turned up the next year in a CD-ROM where you wanted thru a city at
night, meeting people and situations and choosing a reaction 'temperature'
on a spectrum-bar at the bottom of the screen...


>[Coming next: The player's character in IF, and the game itself]
>
>Roger Giner-Sorolla New York University gi...@xp.psych.nyu.edu
>~~~~~~~~~~~~~~~~~~~ Department of Psychology ~~~~~~~~~~~~~~~~~~~~~
>~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
>"Sur l'oreiller du mal c'est Satan Trismegiste
> qui berce longuement notre esprit enchante' ..." -- Baudelaire

Great series, Roger. Chris Crawford would very likely pay $100/page
for it...


j

-==---
... i loved you, so i drew these tides of men into my hands... _+m"m+_"+_
lynx http://www.mcs.net/~jorn/ ! Jp Jp qh qh
best-of news:alt.music.category-freak ! O O O O
ftp://ftp.mcs.com/mcsnet.users/jorn/ Yb Yb dY dY
...and wrote my will across the sky in stars. --R.Graves "Y_ "Y5m2Y" "


Neil K. Guy

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Apr 28, 1996, 3:00:00 AM4/28/96
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Jorn Barger (jo...@MCS.COM) wrote:

: I suggested a control-dimension of warm-response/cool-response that


: turned up the next year in a CD-ROM where you wanted thru a city at
: night, meeting people and situations and choosing a reaction 'temperature'
: on a spectrum-bar at the bottom of the screen...

An acquaintance of mine looked at the code for that CD-ROM (in Director
Lingo) and claims it basically doesn't pay much attention to the
warm/cool bar and really just turns out random responses. Oh, well. Nice
concept though, if a little naive.

- Neil K. Guy

--
Neil K. Guy * ne...@sfu.ca * n...@vcn.bc.ca
49N 16' 123W 7' * Vancouver, BC, Canada

Crisis gal

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Apr 28, 1996, 3:00:00 AM4/28/96
to

In article <4lvsa5$9...@Venus.mcs.com>, jo...@MCS.COM (Jorn Barger) writes:

>and sci.cognitive where people have been discussing emotion.]
>
>

I hate to dissappoint you but that don't discuss much of that here.

Crisis

Jorn Barger

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Apr 28, 1996, 3:00:00 AM4/28/96
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In article <4lvvm4$h...@milo.vcn.bc.ca>, Neil K. Guy <n...@vcn.bc.ca> wrote:
>: I suggested a control-dimension of warm-response/cool-response that

>: turned up the next year in a CD-ROM where you wanted thru a city at
>: night, meeting people and situations and choosing a reaction 'temperature'
>: on a spectrum-bar at the bottom of the screen...
>
> An acquaintance of mine looked at the code for that CD-ROM (in Director
>Lingo) and claims it basically doesn't pay much attention to the
>warm/cool bar and really just turns out random responses. Oh, well. Nice
>concept though, if a little naive.

I'm dubious. I wouldn't expect more than a binary choice, but a
cool/warm branch would be easy and (barely) literary...


j

Roger Giner-Sorolla

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Apr 29, 1996, 3:00:00 AM4/29/96
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On 28 Apr 1996, Jorn Barger wrote:

> That _is_ very interesting! So, each character has a fixed number of
> moods (what are they?)... but these are just metaphorical 'rooms', of
> course-- you still have to have regular space... surely?

> For those of us too lazy to do the research, will you spell out the
> table Kim uses?

It's a metaphor, of course, and somewhat unrealistic when it comes to
multiple players, as the automaton doesn't keep track of who is giving
what input. To be honest, I did this a while ago and I can't remember
the details of the table, but the example I gave shows three moods:
"initial", "interested" and "friendly".

I think the talk about "theories of seduction" (and this applies too to
Roger Carbol's post detailing a complex simulation of emotional states) in
this forum, is interesting, but that we should keep in mind the difference
between a simulation and a game. A game probably will not require eight
stages of hunger in an NPC, but who knows? If a main goal of the game is
to scrape up enough food to keep your beloved dog alive, perhaps you want
this. In any case, the mechanics of characters in a game should be
tailored towards the needs of the game; and the mechanics of characters in
a work of fiction, even an interactive one, should be worked out within
the framework of plot, which may dictate only a relatively small number of
possible emotional states.

Having said this, Mr. Carbol's post definitely makes me want to share
some psychological/cognitive theory on appraisals and emotions with you
all. As soon as my next "Mimesis" post is complete, I'll try and present
a fairly simplified version of two-factor emotion theory, as well as
outline more complex models. (Hm, this could also be the start of a
scholarly article I've been meaning to write for some time...)

> > I can't help but suspect that character-based puzzles may have taken on a
> >stigma from early attempts like the seduction puzzles in "Softporn."
>
> Remind me how these worked...?

Talk to the girl and she takes an interest in you; dance with her, then give
her a flower and a ring and she goes home with you. Reeeeal subtle.


> Great series, Roger. Chris Crawford would very likely pay $100/page
> for it...

Who? Where? Details, please!

Roger Giner-Sorolla New York University, New York, NY
gi...@xp.psych.nyu.edu Dept. of Psychology (Social/Personality)
~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
"The F.B.I. has said that it believes he was a student of the history of
science, but on the evidence here he was a social psychology major with a
minor in sociology, and he shows all the distressing hallmarks of the
worst of that academic breed." -- Kirkpatrick Sale on the Unabomber, 9/95


Matthew Daly

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Apr 30, 1996, 3:00:00 AM4/30/96
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In article <4lpcos$6...@news-s01.ny.us.ibm.net> bl...@ibm.net writes:
>
>Currently, I'm leaning toward the idea of adding some conversational verbs to
>the standard "Ask about ..." and "Tell about ...". "Insult Roger" "Flatter
>Linda" "Argue with Dobson", that sort of thing.

This is a cool idea, but be cautious around it. I have no idea how old
the game is, but I played "Nine Princes in Amber" many many winters ago,
which had a conversational scheme like the one you describe. (Much larger,
actually. It included verbs like "Berate" and "Heckle" in addition to
"Insult".)

The problem was that you had to use the precise combination of verbs in
order to "solve" the conversation, and it was a real pain in the side.

But in general, it should be as easy and natural to manipulate NPCs as it
is to manipulate items, IMO.

-Matthew Daly

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