My research interest is in the investigation of the essence of rationality and knowledge and its application to
artificial intelligence. We mainly investigate how a rational agent acquires knowledge, represents the knowledge by
logic, and acts and makes decisions based on logical reasoning. In particular, our most interesting topic is the rationality
criteria of logical reasoning under the environment of incomplete and insufficient information.
Technically, a major part of our work involves the study of properties of different types of logic for uncertain
reasoning, for example, fuzzy logic, possibilistic logic, modal logic, conditional logic, nonmonotonic logic, etc.
Furthermore, we have also developed some uniform frameworks for these different types of logic.
Recently, we have also concentrated on the formalization of the logical properties of intelligent agents. Based
on different logical systems like epistemic reasoning, deontic reasoning, preferential reasoning, etc., we can discuss
some characteristic features of intelligent agents.