Cagey

Chief has used the word cagey to describe both himself and other patients on the ward. Although he originally uses the word to describe himself as sneaky and deceptive, he later says that McMurphy had gotten mad at the ward patients for being cagey. The word itself perhaps comes from whatever created the word cage, which could have a number of connotations. In this case, as the patients on the ward have already been described many times as birds, this could mean that by being cagey, the patients are trapped...in a birdcage and are therefore able to be manipulated. When you really think about it, Chief pretending to be deaf and dumb may help him survive, but it also cements the fact that he is trapped inside the ward and will essentially remain there for the rest of his life. He is taking no risks. McMurphy wants to inspire the ward (whether it is for his good, theirs or both we don't really know) to act in a way totally opposite than survival tactics and wants to challange the order of the road, and maybe because of the patients being trapped birds they are not fully able to do that.