Chris Crawford on Interactive Storytelling (39 page)

Another aspect of character that could be included in a personality model is mood. As with intrinsic personality traits, mood is difficult to define precisely. Fortunately, the task of including mood variables isn’t so complicated. My own personality model uses three moods:
Anger/Fear
,
Arousal/Revulsion
, and
Joy/Sadness
. Note that each mood is bipolar.

But anger is not the opposite of fear.

I think it is. Think in strictly behavioral terms: How are anger and fear manifested? The classic answer is “fight or flight,” and the brains of most animals have a basic mechanism for gearing up for one or the other. Adrenalin pours into the bloodstream, heart rate soars, breathing becomes deeper and faster: You’re ready for action. Whether that action is fight or flight doesn’t matter. Inside the brain, fight and flight are just two sides of the same coin, and they can’t share the same coin unless they’re opposites.

Mood spontaneously diminishes. No matter how angry you become, the passage of time will surely diminish that anger. Although the actions of others can both intensify and diminish moods, these moods can nevertheless diminish all by themselves. The storytelling engine, therefore, must examine each Actor’s mood at regular intervals and relax it toward zero. This is most easily accomplished by multiplying the mood at regular intervals by some value less than 1.00. The smaller the number, the more quickly the mood decays.

Including fatigue or even hunger as a mood is also possible, but as these states require specific actions to ameliorate, I treat them separately from moods. Moreover, because they’re more physical in nature than emotional, I prefer to minimize their role.

I offer for your consideration the personality model I have ended up with after many years. I do not claim this model to be the best of all possible models—just the one I have found most workable.

Integrity:
This variable is close to the common use of the term. Actors with high
Integrity
always keep their word, never tell lies, and never reveal secrets. Actors with low
Integrity
break their promises, lie, and reveal secrets.

Virtue:
This is the degree to which an Actor takes other Actors’ needs and desires into account when making decisions. Actors with high
Virtue
make choices based on what’s best for other actors (themselves included). Actors with low
Virtue
are selfish, self-centered, and egotistical. They always place their own interests ahead of other considerations.

Power:
This variable represents the ability to wreak physical, financial, or social injury upon others. Actors with lots of
Power
have the capacity to do harm, but not necessarily the motivation.

Intelligence:
This variable represents the ability to make correct decisions. Actors with high
Intelligence
tend to make the most efficacious and pragmatic choices. Actors with low
Intelligence
often make incorrect judgments.

Attractiveness:
This variable represents an Actor’s physical appearance. A female Actor with high
Attractiveness
is pretty; a male Actor with high
Attractiveness
is handsome.

Anger/Fear:
Positive values denote anger; negative values denote fear.

Joy/Sadness:
Positive values denote joy; negative values denote sadness.

Arousal/Disgust:
This pairing counterbalances arousal, normally thought of in its sexual manifestation, with disgust, normally associated with smell and taste. In this case, however, arousal is used to indicate any heightened sensuality. Licking your lips before digging into a meal constitutes arousal.

Adrenaline:
Think of this variable as “the speed with which adrenaline pours into the bloodstream.” It controls the rate of change of
Anger/Fear
. High values describe an Actor who angers or runs quickly.

Manic/Depressive:
Actors with high levels of this variable soar to peaks of joy or plunge to depths of despair every time they look at the mail; controls
Joy/Sadness
.

Sensuality:
This variable controls the rate of change of
Arousal/Disgust
. An Actor with a high value of
Sensuality
is readily aroused and easily disgusted.

AccordIntegrity:
This variable is close to what’s known as gullibility; its negative sense would be close to suspiciousness.

AccordVirtue:
This variable represents the willingness to see the good in other people. An Actor with high
AccordVirtue
would be more sympathetic and not respond as harshly to another Actor’s evil actions.

AccordPower:
This variable might be called timidity. An Actor with high
AccordPower
overestimates the power of others. An Actor with low
AccordPower
underestimates the dangers of any social situation.

AccordIntelligence:
No simple English term adequately captures this concept. An Actor with high
AccordIntelligence
more readily defers to others’ judgments, thinking them wise. An Actor with negative values of
AccordIntelligence
thinks everybody else stupid and rejects their suggestions.

AccordAttractive:
This variable also has no ready translation into English. Behaviorally, an Actor with high values of
AccordAttractive
sees everybody else as beautiful. This variable makes more sense in terms of self-image, in which case you might call its negative value vanity.
AccordAttractive
might also translate into something like lust.

PerIntegrity:
This variable is very close to what’s known as trust. An Actor who has high
PerIntegrity
for another acts on the belief that the second Actor will honor his promises, keep secrets, and not tell lies.

PerVirtue:
This variable represents the
Virtue
of one Actor as perceived by another.
PerVirtue
toward another substitutes for
Virtue
in oneself. In other words, one person’s
PerVirtue
for another operates in exactly the same way he would behave if he had a similar amount of
Virtue
. Indeed, it might be best to add
Virtue
and
PerVirtue
together in calculations.

PerPower:
This variable indicates the relationship engendered by
Power
; it’s close to fear. High values of
PerPower
induce an Actor to defer to the judgment and carry out the wishes of the powerful one. An Actor with little
PerPower
toward another is less inclined to carry out the second Actor’s wishes. However, true fear is more precisely a combination of
PerPower
and
PerVirtue
. In other words, an
Actor doesn’t fear another unless he perceives the second Actor to be powerful and amoral.

PerIntelligence:
This variable represents one Actor’s perception of another’s
Intelligence
; it’s close to the concept of respect, although respect can also represent high perceived
Virtue
or even high perceived
Power
. An Actor with high
PerIntelligence
for another defers to the other’s judgment more readily. An Actor with low
PerIntelligence
for another doesn’t give much weight to the other’s recommendations and wishes.

PerAttractive:
This variable indicates the degree to which an Actor perceives another as attractive. This value might be heightened by
PerVirtue
, and vice versa.

But these traits and relationships aren’t orthogonal. You could make a good argument that
PerIntegrity
and
PerVirtue
are correlated—do you really trust somebody you don’t like? Doesn’t this break your rule for orthogonality?

Well, yes, there’s some overlap. This system’s orthogonality is not perfect. Orthogonality is an ideal to strive for, not an absolute requirement. This model has what I consider an acceptable degree of orthogonality.

Nor is this set complete: It doesn’t address traits such as greed or pride.

Both greed and pride can both be approximated through the existing personality set. For example, an Actor with negative
Virtue
puts his own interests ahead of others’ interests, and so tends to be greedy. Similarly, pride is a combination of negative
Virtue
and negative
Intelligence
.

There’s no question that this personality model has its weaknesses. Human beings are messy creatures, and I don’t think we’ll ever find something as neat and clean as the RGB system for color. That’s what makes storybuilding an art form—you simply have to make artistic judgments about the system you use. I’m sure there are lots of other ways of slicing the cake. In designing a personality model, you must treat orthogonality as a desideratum, not an absolute rule. You also want completeness and conciseness, but will never truly achieve them. Perhaps one day some genius will come up with a system that’s perfectly orthogonal, complete, and concise. When that day comes, we can all rejoice. Until then, we just have to make the best approximations we can.