Abstract: A knowledge system including an expert system and a complementary data base. The knowledge system is provided to answer requests, and each request has a record including a plurality of parameters and values for those parameters. The expert system is provided to process the record of a specific request to answer that request, and the complementary database stores a plurality of records of requests having known answers, and any request from a user is preprocessed by searching the complementary database for a record identical to the record of the request. If an identical record is found, the known answer to the request having that identical record is given to the user to answer his or her request; however if no identical record is found in the complementary database, the expert system is invoked to answer the request.