18. The method of claim 13 , wherein the formally represented knowledge further comprises one or more entity lists wherein each entity list contains a list of one or more entities associated with other entities contained in the entity list, and wherein assigning the index further comprises extracting an entity contained in an entity list from a particular piece of content in the corpus and associating a particular entity list to the particular piece of content.
19. The method of claim 18 , wherein assigning an index further comprises assigning a particular facet to a particular piece of content when a term in the piece of content is contained in the synsets of the facet.