Acquiring object-knowledge for learning systems

A novel approach to interactively acquire knowledge about new objects in a logic environ- ment is presented. When the user supplies an unknown fact containing unknown objects (constants), the system will ask interesting membership and existential queries about the objects. The answers to these questions allow the system to update its knowledge base. Two basic strategies are implemented: one that examines existing Horn-Clauses for the predicate and another one that uses types. Furthermore, a powerful heuristic, based on analogy, to pose the most interesting questions first is presented.