Sweet, Sweet Karma
Last time I ended with an explanation of Fallout 3's Radiant AI, and the game's morality system directly works together with it to create the experience of choice. Fallout 3 has a morality system called the Karma System, and it is a fairly simple one. Each significant action you take, whether it be to shoot up a bar or save a cave full of orphaned children, gives positive or negative karma. If you were to visualize it, your character is a tiny slider on a linear scale, and you start directly in the middle. Each action which would accrue karma would take you closer to the left (negative) or right (positive). So how does this interact with the Radiant AI?
"Oh, it's you..."
As you accrue karma, positive or negative, interesting things begin to happen. As you enter a town, if you've been playing the valiant hero, you may overhear some NPCs chatting about how you saved that whole village a couple miles away, or exclaim one of your other heroic acts. Likewise, if you've been acting in more dastardly ways, the NPCs will shy away from you, some may even call you names, and don't think you'll be getting good prices at the shop as a villain either. This is the Radiant system at work; entwining the non-linear scheduling protocols of the NPCs with your choices and decisions to create a personal narrative that spans the whole game-world.
Resources (for Part I & II)
Wong, K. (2013, August 1). Morality systems in roleplaying games. Retrieved from http://the- artifice.com/role-playing-games-morality-systems/
Mullon, R. (2012, April 18). What's new in skyrim: New radiant ai and radiant story. In The Altered Gamer. Retrieved April 24, 2014, from http://elder-scrolls.alteredgamer.com/tes-5-skyrim/116302-whats-new-in-skyrim-new-radiant-ai-and-radiant-story/