The system includes system interaction management server (MS), certainty MS, data syncretizing MS, rule MS, display terminal. Connecting information integration system, the system interaction MS sands data to be interfused and relevant information to data syncretizing MS. data syncretizing MS syncretizes the inputted data through inference, and provides result for users through display terminal. In batch mode, user determines or further processes syncretized result. System returns final syncretized result back to external information integration system. Based on final syncretized result of system and QoS of each data sources in this syncretizing procedure, certainty MS modifies certainty of data sources. User can manage rule base in rule manager and certainty of each data source in data source certainty manager. Features are: legible modules, dynamic performance, generality and flexibility.