In the interaction with others, we read other's mind or estimate other's inner states, and utilize them for predicting other's behavior and deciding own behavior. Moreover, we utilize them for making someone do as we wished. In this study, we attempt to propose required functions for decision making of own and other's behavior depending on the mind reading processes and suggested mechanisms for realize these functions. Three investigational situations such as advising clothes to a customer, explanation of operating procedures, and misleading the other's belief were conducted and decision making processes of own behavior were analyzed depending on the recorded conversation during these situations or interview on video-playback. These results proposed two required functions: 1) acquisition of other's view of environment and detection of differences between own and other's view, 2) estimation of other's rules for decision making and operating them along with own will.