Quentin Elhaik, Marie-Christine Rousset, and Marie-Claude Gaudel
Description logics have good representational properties and their computational properties are well understood. However, one of their main drawback is that their current reasoning algorithms have an inherent black-box nature, i.e they don’t make explicit how subsumption inferences are obtained. This is an important drawback for providing explanation or debugging services. Description logics with a reasonable expressive power contain different constructors the combination of which can lead to numerous, complex and varied forms of subsumption relation. Consequently, some subsumption relations are complex and need to be explained to a user or to a terminology designer. The point is not to explain to users or designers how subsumption is computed but how a complex subsumption inference can be decomposed into different simpler inference steps. For KBS, rules have shown to be a formalism that is well appropriate to support trace capabilities for both explanation and debugging purposes.