1. A method of obtaining rule-based information in an ontological system comprising: receiving an indication of an occurrence of an event from at least one managed element; wherein the event indicates a change in state of the at least one managed element; accessing a first ontology and obtaining selected information associated with the occurrence of the event from the first ontology; accessing a second ontology and obtaining at least one first rule associated with the occurrence of the event from the second ontology by using at least in part the selected information from the first ontology; and applying the at least one first rule and responsively determining a cause of the event.