4. The system of claim 1 , wherein the characteristic determination unit measures and stores the emotion expression information for each emotion expressed by the user, and determines the characteristic information for each such emotion based on the measured emotion expression information.
1. A system using a processor for reasoning an optimized service for influencing the emotive state of a user, the system comprising: a ubiquitous system unit for collecting information about surroundings of a user, and for storing the information in database; a context awareness unit for recognizing a state of the user based on the information collected by the ubiquitous system unit, and for generating context information; a characteristic determination unit for determining characteristic information for each emotion, the characteristic information being used to determine which emotion the user feels; an emotion awareness unit for comparing the characteristic information with the at least one piece of emotion expression information, for recognizing a current emotional state of the user, and for generating emotion information; a combination unit for combining the context information and the emotion information; and a service selection unit for reasoning and selecting a service for influencing the emotive state of the user based at least in part on the combination result of the combination unit, wherein the ubiquitous system unit includes a sensor network for collecting state-related information associated with the state of the user; and a user interface for collecting at least one piece of emotion expression information expressing the emotion of the user.