Karsten Homann Abstract
LEMMA (Learning Environment for Mathematic and Mathematical Applications) is a knowledge based environment which allows to integrate computer algebra and theorem proving.
This environment is based upon a hybrid knowledge representation system, Mantra (Modular Assertional, semantic Network and Terminological Representation Approach) which is semantically unified and sound. The adoption of a four-valued semantics ensures the decidability of inference algorithms. In addition, it provides communication among the usual knowledge paradigms and may be used as a rule-based system to model the procedural knowledge of a domain.