5. An information query system for querying desired information by using inputted abstract conceptual expressions expressed by combinations of concepts and relations between the concepts as querying conditions, comprising: an input device for inputting an abstract conceptual expression as a query expression; a dialogue window for displaying query expressions; means for driving said dialogue window to display a network indicating mutual relation between different assemblies of concepts satisfying relations added to a current concept; means for rewriting said dialogue window representing the network, responding to a modification of said dialogue window displaying query expressions, and rewriting the display of the query expression by replacing said concept by the current concept in the query expression, responding to a modification of the current concept to a certain concept displayed by said dialogue window displaying query expressions; and means for querying a database containing various types of information according to the rewritten network and the rewritten query expression.
7. An information query system according to claim 5, wherein said means for rewriting the display includes means for imposing conditions one after another to the concept in the query expression, the current concept moving freely among the concepts in the query expression.