So far, I have described an unweighted connectionist system. That is, I have described the existence of connections between storyatoms, but have said nothing about which of those consequent storyatoms might actually be chosen. In my standard Guy AttemptsToKiss Gal example, the gal has a variety of options, from SpurnKiss to Kiss to RedHotKiss, but which will she actually take? And why?
There are two aspects to this problem: first, the fact that the options will be chosen with different frequencies, and second, that those frequences must depend on the interpersonal situation.
The first aspect is obvious, but the second one brings us right to the heart of the concept of interactive storytelling. Stories are at root about choices. As Aristotle noted, a character is revealed by the choices that s/he makes. Thus, the most important component of any interactive storytelling system is its method for handling choices made by characters. The choices must be made in a manner consistent with the personality of the character, that character's relationships with other characters, and the historical context in which the character makes his/her choice. This is going to be complicated.
The basic approach I use relies on something I call a "weighting equation", although I suspect that "inclination equation" might be more descriptive. I shall use this latter term here.
An inclination equation is a formula created by the storybuilder that can be used to calculate a character's inclination to select a particular choice. Thus, if our example gal is trying to decide between SpurnKiss, Kiss, and KissRedHot, she will have an inclination equation for each of these three options. Each inclination equation will use personality traits, relationships, and contextual information to calculate a number, which I call the character's inclination to take that option.
Here is a simple example of what I mean. Our example gal might have these three inclination equations:
These three equations utilize imaginary elements from our "Personality Model", which is a collection of numbers that describe each character's personality and relationships. For example, the first term is Loyalty[Gal for her SignificantOther]. This would be a number representing how loyal this gal is to her sweetheart. If she has a lot of loyalty, then this number will be big. If she has little loyalty, then this number will be small. Let's suppose that she has a boyfriend, but they're in the midst of breaking up, so her loyalty to him is a meager 23.
The second term is Affection[Gal for Guy]. That's another relationship variable, and it keeps track of how much the gal likes the guy. Let's suppose that she likes this Guy quite a lot, say 57.
The third term is Libido[Gal]. This is a personality trait, not a relationship; it measures just how libidinous this lady is. She's a pretty hot lady, say 31.
Now, if we plug these numbers in, we get the following results:
Her highest inclination is to Kiss the guy, so that's the choice she makes. Of course, if this were another gal, and another guy, the numbers might be completely different, and the choice might then be different. That's the whole point of this exercise!
You might object that this is entirely too simplistic -- and you would be right. Clearly, a gal's decision to kiss a guy involves more than just her loyalty, affection, and libido. Other factors would enter into her decision, such as whether she trusts the guy, or whether she's kissed him before. If that's how you feel, just change the inclination equations:
Again, these are simplified representations of how you would write the equations, but they capture the idea: if you want greater dramatic fidelity, you simply add more terms to the inclination equations.
At this point, I want to make an important point about the difference between dramatics and simulation. The more technical reader might argue that there must be a "correct" set of inclination equations; why not just write that correct set once and for all and be done with it?
The answer is that this is drama, not simulation. If this is an action-packed, Arnold Schwarzenegger macho kinda story, then the gal's decision to kiss the guy will be very simple: if he killed all the bad guys, she kisses him; if not, he's dead anyway. On the other hand, if this is a romantic female kinda story then the gal's decision to kiss the guy will only come at the very end of the story, after all sorts of verbal wrangling, hand-wringing, and tear-shedding. In other words, creating the inclination equations is a highly artistic decision that must be suited to the nature of the story.