In what ways does the novel challenge us to reconsider our notion of who isnt suffering from a mental illness?

There is deffinately a blur between sanity and insanity. At times Chief Bromden seems almost visionary in his perceptions about the world. McMurphy goes into the institution seemingly sane yet is driven to near insanity by Nurse Ratchet and the system. Whichever the way you examine it, the mental health system was not healthy in any way. A really good GradeSaver link is below. Scroll down to "Mind vs. Matter."