Over a wide range of human creations, there is a common aspect of tension and release. In other words,
- Something happens to build up tension. People get increasingly anxious about what will happen next.
- Then something happens to "resolve" or "release" the tension. The people become relaxed and satisfied at the outcome.
In STORIES, tension is increased and decreased by things that happen in the plot. Since the ancient Greeks, people have talked about plots as "rising" and "falling" when the tension level goes up and down. There are entire theories of dramatic structure that attempt to analyze the flow of tension in plays, films, and novels. Playwright William Gibson described it as the tying and untying of complex knots, and Prof. Allen Tilley described the rising and falling as a "plot snake" that undergoes some predictable twists in many kinds of stories. Even modern sci-fi authors are getting into the act by cleverly unpacking some "classical" ideas of narrative structure in new ways.
In MUSIC, the buildup and release of tension is often done by changing key. A piece begins in a "home key" and then gradually develops away from that key, sounding more and more different (and even dissonant) in comparison to the initial "ideas" stated at the beginning. For most listeners, the experience of tension is unconscious and emotional. Only experts will explicitly think: "Hmm, I wonder how the composer will figure out how to come back to the home key after complicating things so much?" But the experience is real.
In MATHEMATICS, some have found the development of formal proofs to contain a kind of rising and falling tension. This was described in Douglas Hofstadter's monumental book Godel, Escher, Bach. Proofs begin with some very simple premises, and they end with a simple conclusion (or at least they're supposed to!), but in the middle they can be quite complicated. A reader trying to follow the process can experience many of the same feelings of anxiety about how it will all get resolved.
There are plenty of other possible examples. (How about roller coasters? The tension and release is felt viscerally!)
In RPGs, the tension comes from playing a character who is undergoing exciting, and often life-threatening, adventures. Done right, it can be an experience like no other. The one important difference here is that in these types of games, the "plot" isn't prewritten. The story comes about as a combination of things the Game Master (GM) has planned out, the choices made by the players, and the random results of the dice.
There are debates in RPG circles about how much should be prewritten and how much should evolve from moment to moment. Some GMs can sometimes go too far in "railroading" the players into a pre-planned set of events. Others can sometimes be too unprepared in just building a simple "sandbox" for the players to wallow around in with no interesting "plot hooks" to bite on. Balance seems to be best.
In the Glass Bead Game... well, there still is no real Glass Bead Game. In the novel, Hesse describes public performances of games that certainly seem to embody many of the above characteristics of tension and release. Still, I feel that any future implementation of the GBG should have this whole tension/release thing written into its DNA. I don't know if it needs to be "self-referential" about it (like Hofstadter implied: a system that "knows" its own current level of tension). However, it does need to be able to express this common idea in a common language, no matter whether one is discussing a play, a symphony, a roller coaster, or a game of D&D....