In this paper, we reconstruct our mental model based on discussion in philosophy of mind. From the point of philosophy, there are two approaches, monism which deals mind and matter with the same one and dualism which says mental phenomena are non-physical. In this research, we use "interactionist dualism." Our mental model is separated into physical network which deals with deductive reasoning, affective network which calculates aroused emotions, and mood network which transits the mental state of the computer agent. Furthermore, some nodes in mental network and physical network are connected each other based on causal relationship so that complex facial expressions are represented as the variance of the agent behavior.