Introduction to Description Logics

Logic and Computation Courses

Introductory Course

Introduction to Description Logics,
Ivan Varzinczak (Artois University, France)

This course provides an introduction to Description Logics (DLs) in the context of knowledge representation and reasoning (KRR). DLs are a family of logic-based KRR formalisms with interesting computational properties and many applications. In particular, DLs are well-suited for representing and reasoning about terminological knowledge and constitute the formal foundations of semantic-web ontologies. There are different flavors of description logics with specific expressive power and applications, an example of which is ALC and on which we shall have a strong focus in this course.

We start with a motivation for representing and reasoning with ontologies. We then present the description logic ALC, its syntax, semantics, logical properties and proof methods, especially the tableau-based one. Finally, we illustrate the usefulness of DLs with the popular Protégé ontology editor, a tool allowing for both the design of DL-based ontologies and the ability to perform reasoning tasks with them.