Idea Mapping means taking the player through a variety of viewpoints, usually inconsistent ones, during the game.
I was brought in as a designer/writer on a game about a man who hunts monsters. Unfortunately, the basic game design was fairly complete by the time I came on board.
It didn't allow me to do any Idea Mapping. If I had been part of the original design team, I probably would suggested that:
The first two points are done in Blade Runner, where at first we feel that the replicants are inhuman monsters. By the end, however, our opinion has changed and it seems clear that some of the replicants are much more "human" than those who are trying to destroy them.
That's Idea Mapping.
The third idea I would have suggested is harder to make work in a game. I'd probably put the player in a position where the player (i.e., the player's character) was near two people or monsters the player liked, but who were both in mortal jeopardy and the player can only save one of them.
Later in the game, a friend of the person (or the creature) the player allowed to perish, would call the player a monster. Perhaps several NPCs the player cared about and respected would feel this way about him or her, and the player's character would be shunned.
It would take artful writing to make all the intended emotions carry weight, but if those emotions were brought to life, it would certainly be an interesting exploration of the theme of "monsters."
Idea Mapping Is Often Synonymous with "Theme," But Doesn't Have to Be
In the preceding example, there's really no difference between Idea Mapping and "theme," because the ideas the player would hold at different points all revolved around a particular subject ("monsters"). "Monsters" would be the theme of the game. Here, the term "theme" means "a subject central to the story and explored from different points of view, but with no final conclusion drawn."
However, Idea Mapping could be performed on subjects other than the theme.
For instance, in this game, at one point you could make viable the idea that a person should do his or her noble work (hunting monsters) alone. At another point, it would be clear that it's better to hunt monsters as part of a group.
These diverging ideas would be "Idea Mapping," but they wouldn't be central enough to the story so as to constitute its theme.
If this all seems a bit irrelevant to emotion, because it deals with ideas, I'd like to point out that in Lord of the Rings Fellowship of the Rings, the idea of "power" is explored from many points of view:
This highly artful Idea Mapping helped deepen the plot and contributed significantly to the emotional scope and impact of Fellowship of the Rings.
An Important Note: Ideas Are Not Enough
It's important to point out that ideas in themselves are dry and don't deepen emotion in a game. Ideas only contribute to a game's emotional power and resonance when they affect or manifest themselves through the acts or decisions made by characters we identify with, care about, fear, or hate.
Therefore, Idea Mapping can't deepen emotion in the absence of the artful use of techniques that cause players to become emotionally involved with NPCs (Chapters 2.10, 2.11, 2.13, 2.14, and 2.15) and techniques that cause players to become emotionally involved with the role they're playing and the world they play in (Chapters 2.18, 2.19, 2.20, and 2.21).
Better Late Than Never, But Better Early Than Late
Emotion Mapping and Idea Mapping, like just about all the Plot Deepening Techniques, can only be effectively put into a game when they're part of the initial design. This is true for many Emotioneering techniques. How much Emotioneering can be done, both in terms of quantity, variety, and power, depends on how early they're woven into the game design and gameplay.
When I'm asked to involve myself on a game in its last stages, I can polish the dialogue and often enrich the characters, but there's a tremendous amount that I can't do. For instance, I certainly can't do any Emotion Mapping or Idea Mapping. In fact, I can't use any of the techniques described in this chapter.