1. A document filing system for retrieving stored information based on an operator's partial or abstract description of said information comprising: means for storing said knowledge base in which knowledge is represented in terms of concepts, each of which has a name associated therewith, relations each of which connects two of said concepts, at least some of said relations being subsumption relations, each of which is an ordered relation representing a superclass relationship between said concepts and generic relationships, each of which exists between two classes of concepts and which represent a possible relationship between two concepts each of which is a concept subsumed by one of said two classes, respectively; means for interacting with said user for presenting guiding information from part of said knowledge base to said user, and for allowing said user to enter information necessary to register said partial or abstract descriptions to retrieve documents, and information necessary to update said knowledge base; means for storing programs and data necessary for managing said knowledge base and for carrying out document registration and inferential retrieval; means for controlling operations of said system according to said programs stored in said storage means, including matching an abstract description of a concept entered by said user with a concept stored in said knowledge base, means for inputting said documents, means for storing a large amount of documents inputted by said inputting means, and means for displaying the retrieved documents wherein the contents of said knowledge base is arranged in a first table means for storing tables which record at least a concept identification number and names for said concept, second table means for storing tables which record at least two concept identification numbers representing subsumption relations between two concepts, third table means for storing tables which record at least an identification number of a generic relationship which is a relationship between any two concepts which represents a possible relationship between two different concepts each of which is subsumed by one of said two concepts, respectively, and two character strings corresponding to said generic relationship for two directions, and fourth table means for storing tables which record at least two concept identification numbers and one generic relationship identification number, representing a specific relation defined between two concepts.