This particular lesson was developed for Cognitive Skills I, a central course in cognitive restructuring at the Mt. Olive Correctional Center. In this lesson the author developed a series of classroom activities to allow students to examine and assess current beliefs they possess, and to understand how these beliefs--whether judged rational or irrational (or valid or invalid) through an objective process of assessment--are connected to their thoughts, feelings, and actions. The essential goal, therefore, of this lesson is to impart to inmates a self-reflective tool to allow an inmate to be his or her own "Best Critic" through self-assessment of one's own belief system. (Contains 4 figures.)