1. A computer-readable storage medium comprising code representing instructions to cause a computer to produce a concept semantic network (CSN) from an ontology by: for each class in the ontology, converting that class into a concept in the CSN, that concept corresponding to that class in the ontology; converting each property of each class into a child concept of the concept corresponding to that class in the CSN; converting each subclass, each object, and each restriction of the ontology to distinct concepts in the CSN; and converting each hierarchy in the ontology to a concept hierarchy in the CSN, the hierarchies in the ontology comprising a property hierarchy.