When information is inputted from the recognition object, the emotion module discriminates the type of the inputted information (step ST1) and changes the emotion level of each emotion unit using the parameter corresponding to the inputted information (step ST2). The emotion module selects the emotion unit having the maximum emotion level from among the emotion units having the emotion levels exceeding the threshold value. The selected emotion unit notifies the object that is requesting the output, for example, the behavior-production object, of that information.