This essay is about the principles and rules that control persuasive computer games. The term persuasive games mean computer games, video games and other similar artifacts that are produced to shape opinion. The rhetorical scholar Ian Bogost at Georgia Tech claims that this kind of games mainly get their persuasive power by using procedural rhetoric and that games as a medium gives special conditions for procedurality.  By procedural rhetoric Bogost means an argumentation that is based on rules and choices, as opposed to texts, movies and images. (Bogost 2007). Bogost describes these procedures as quite specific for games and claims that they differ qualitatively from ?ordinary? rhetorical arguments even if they just as other arguments work by establishing enthymems.