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By phil

Dimensional Story Space

On 28, Nov 2011 | In Blog, ideas | By phil

I wrote this article on interactive story telling in 1992 for a group called Interactive Expression, a group of us in the Los Angeles area who worked at Philips and other early “multimedia” companies. We got together to discuss the new medium of Interactive Media.


Interactive stories are often thought to be a series of choices made by the active viewer or participant. Go left, pick up a key, fall in love, steal a car, etc. Besides some challenges in terms of plot, character development, and consistent theme, this approach has fundamental problems related to a mathematical problem.

The Combinatoric Explosion

If the story is seen as a series of binary choices–do this or do that–the range of possible outcomes becomes very large in just a few choices (and the problem is made much worse if the number of choices is greater than two at each decision point). For example, after only six choices, the number of different story lines is sixty four, as can be seen in the drawing to the left. If each choice leads to a unique story line (in other words, the different choices do not result in common outcomes), the space requirements and production costs for such an interactive expression become prohibitive before the participant spends ten minutes with the product. Imagine trying to write, videotape, and assemble 64 separate story lines.

Abandoning The Traditional Narrative

The combinatoric explosion described above is a consequence of thinking in terms of the traditional narrative. But if the interactive expression is seen in different terms, the problem becomes more manageable. Imagine that instead of following the straight line of the narrative, the participant travels through a story space. The story space is composed of all the different locations, events, times, and even moods carefully created by the author. The process of moving from one place in the story space to another is determined by their “distance” from one another, and the intervening story places.



The traditional narrative can be achieved in this story space by following a straight line. But a different story line can be achieved by traversing a different path through the story space. In addition, different beginnings and endings can be achieved by entering and exiting the story space in different places.

In this form, the concept of the story space can be useful in constraining the combinatoric explosion. The author creates only those story places within the space that help support the idea being expressed, and size of the production can be contained and made producable. But one can think of the above two dimensional story space as essentially static. To move to a more dynamic model, a third dimension can be added. If the participant makes a significant change to the environment, rather than just traveling through it, they might jump to a different “plane”. For example, by choosing to help the homeless person find a place to sleep, rather than ignoring them, the participant may jump to a different or altered plane in the story space as a consequence of their choice.

While this dimensional approach could lead to the same combinatoric explosion (by creating too many planes), the author controls the explosion by creating only the places and paths-between-places she wants the participant to explore. This is the power of Story Space model. Rather than thinking in terms of a straight line with a beginning and end, the author thinks of a story space through which the participant moves.

Ways of “Moving” in the Story Space

The participant can be allowed to move through the story space in several different ways:

  • Changing locations or times. For example moving from the living room to the bedroom, or from Tuesday to Wednesday.
  • Changing perspectives. The participant can look through the eyes of different characters, or the same character but with different attitudes. One could also be a passive observer rather than one of the characters.
  • Changing scope. Elements of the story can be seen in great detail, or in broad strokes.
  • Changing modes. One could read text, see pictures, or hear sounds.
  • Reordering the sequence. Parts of the story can be viewed in different orders.
  • Altering the space via practical or moral choices. The participant can send the love letter, or deem the protagonist to be an artist.
  • Passive interactivity. The story can change itself, either randomly, or based on the intentions of the author.

I think passive interactivity, while facetiously named, is critical to the success of Interactive Expression. First, participants will soon grow weary of mundane choices and may prefer to sit back and let the story evolve on its own. One night, you might watch the new western and see the goings on down in the valley. The next night, you watch the same western, but see the murder in the mine shaft. Second, if the participant is to be lead to a particular idea by the author, the story may well need to draw the participant along, closing off certain choices, opening up others, and imposing yet others. Even if several different ideas are being presented, and they depend on the path taken by the participant, the story may need to draw the participant to one of those ideas. At a minimum, a certain amount of motivation, fun, change, randomness, and action is likely to be needed, and this can be provided by passive interactivity.

Afterthoughts: Dimensional Story Space

In 1992, I co-founded a salon and newsletter called Interactive Expression, where we explored many of the central issues of multimedia as an art form. For the newsletter, I wrote a piece called that explored some of the problems with interactive story telling. Someone recently sent me an email about it, and it prompted me to look back and think some more about multimedia with the perspective that six years has given me. It is difficult to express something meaningful if the authorial voice is destroyed by the form of the text. And to be honest, I haven’t seen a fully successful interactive text (in any medium). But I think it may be possible, though the result is likely to be very different from what we think of as a novel.

The metaphor I like is sculpture. For example, a Calder mobile is a very dynamic thing, and the viewer may participate by pushing one part and observing the resulting forms. Even the act of walking around a sculpture like The Kiss is an essential part of experiencing the work. The viewer has to participate (i.e. interact) to appreciate the artistic expression. So even though sculptures have this participatory aspect, they maintain their artistic integrity. When you look at a Calder or Rodin, there is no question who made the sculpture. And I don’t think Calder felt his expression was compromised by the fact that a viewer (or the wind) could change the sculpture. This is what I was trying to get at in my essay:

The author can control the [combinatoric] explosion by creating only the places and paths-between-places she wants the participant to explore. This is the power of Story Space model. Rather than thinking in terms of a straight line with a beginning and end, the author thinks of a story space through which the participant moves.

In other words, the author should sculpt the story so the reader can walk around it, and move parts around in order to “see” new aspects and gain a deeper sense of the whole. So far, interactive media has been a disappointment to me from an artistic point of view, though I’ve seen some interactive work that impresses me. In part, this is simply because it’s taking longer than I thought for the new medium to develop. But another problem is the computer and computer screen. It’s kind of like watching Citizen Kane through the slots of a zoetrope. All the power and magic is taken out of the experience. Likewise, there’s something wrong with experiencing an artistic expression in the “mouse and crouch” position. I suspect that interactive expression won’t really work until there’s a medium that feeds the experience rather than detracts from it.