A series of concepts and analysis tools,such as concept of argument,argument schemes,defeasible argument,types of dialogue,relevance and commitment in dialogue and so on,are not only transferred from the field of informal logic into artificial intel.

In the context of autonomic computing, by taking advantage of the non-monotonic knowledge representation and reasoning mechanisms of defeasible logic, a flexible Agent model is proposed, which is capable of accepting the real-time rule modifications, flexibly handling the run-time rule conflicts, and providing efficient non-monotonic reasoning functions.