27. A system for responding to a query initiated at a user device, comprising: one or more data stores having a knowledge base stored therein that includes data representing first knowledge about a plurality of objects using a plurality of relationships among the objects, wherein selected ones of the objects are associated with class objects identifying corresponding classes for the selected objects using class member objects that define class member relationships between the selected objects and the corresponding classes; and one or more computing devices configured to generate a response to the query using second knowledge not statically stored or represented in the at least one knowledge base prior to receipt of the query, the second knowledge being generated by inference from the first knowledge in response to the query, the inference including retrieving one or more first facts included in the first knowledge, the first facts corresponding to first ones of the objects and first ones of the relationships, and generating one or more second facts from the first facts that express at least one new relationship for at least one of the one or more first objects.
27. A system for responding to a query initiated at a user device, comprising: one or more data stores having a knowledge base stored therein that includes data representing first knowledge about a plurality of objects using a plurality of relationships among the objects, wherein selected ones of the objects are associated with class objects identifying corresponding classes for the selected objects using class member objects that define class member relationships between the selected objects and the corresponding classes; and one or more computing devices configured to generate a response to the query using second knowledge not statically stored or represented in the at least one knowledge base prior to receipt of the query, the second knowledge being generated by inference from the first knowledge in response to the query, the inference including retrieving one or more first facts included in the first knowledge, the first facts corresponding to first ones of the objects and first ones of the relationships, and generating one or more second facts from the first facts that express at least one new relationship for at least one of the one or more first objects. 36. The system of claim 27 wherein the data representing the first knowledge in the one or more data stores comprises a plurality of fact representations each corresponding to a relationship between a pair of the plurality of objects, each fact representation including a first object name corresponding to a first one of the plurality of objects, a second object name corresponding to a second one of the plurality of objects, and a relation object name identifying a relation object which defines the relationship between the first and second objects, and wherein the one or more computing devices are further configured to infer the second knowledge with reference to the relationships.