He highlights six characteristics needed from a rhetorical situation that are necessary to creating discourse. A situation calls a rhetor to create discourse, it invites a response to fit the situation, the response meets the necessary requirements of the situation, the exigence which creates the discourse is located in reality, rhetorical situations exhibit simple or complex structures, rhetorical situations after coming into creation either decline or persist. Bitzer's main argument is the concept that rhetoric is used to "effect valuable changes in real" (Bitzer 14).