Fuzzy Description Logic

Course Description

The course covers the study of fuzzy Description Logics as a formalism for representing--and reasoning with--vague or imprecise knowledge.
We will study several variants of fuzzy DLs, that differentiate from each other by their expressivity and their fuzzy semantics. These will mainly be extensions of the classical DLs EL and ALC.
For the logics where this is possible, we will cover practical methods for reasoning over them. However, we will also show that these logics easily become undecidable.


  • basic knowledge of propositional and first order logic
  • knowledge of fuzzy and/or Description Logics is helpful, but not mandatory


The lecture takes place weekly in room APB E005: Tuesdays 16:40-18:10 (DS 6). The first session is on Tuesday the 4th of April. The lecture is accompanied by fortnightly tutorial sessions held by İsmail İlkan Ceylan on Wednesdays, 14:50 o'clock (5.DS), in room APB E005. The exercise sheets will be ready for download about a week before the respective tutorial session from the table on this page. Students are strongly encouraged to solve the exercises and to present them in class. The solutions to the exercises will be discussed in the course.

Week Tuesday Wednesday
4./5. April Lecture
11./12. April Lecture Exercise 1
18./19. April Lecture
25./26. April Lecture Exercise 2
2./3. May Lecture
9./10. May Lecture Exercise 3
16./17. May Lecture Dies Academicus
23./24. May Lecture
30./31. May Lecture Exercise 4
6./7. June Pentecost Holidays
13./14. June Lecture
20./21. June Lecture Exercise 5
27./28. June Lecture
4./5. July Lecture Exercise
11/12. July Lecture Exercise 6
(Session is on Thursday 16:40 o'clock)

Credits / Examinations

Students can earn 3 SWS (2/1/0) by attending this lecture.

Please contact me for fixing a date for your examinations.


Students from the
  • Bachelor Informatik program can use this lecture for the modules INF-B-510 and INF-B-520
  • Master Informatik and Diplom Informatik (Ordnung 2010) programs can use this lecture for the modules INF-BAS6 and INF-VERT6 and INF-PM-FOR
  • Computational Logic program can use this lecture for the modules KR and TCSL
In order to get the credits, students must pass an oral examination at the end of the semester.


Exercise session will be held on Wednesdays 14:50-16:20 (DS 5) in Room APB E005.

All students are encouraged to present their solutions to the exercises, as they are useful for a better understanding of the lecture material.

Exercise sheets will be available online approx. one week before the session.

  • Exercise Sheet 1 (April 12)

Lecture Notes and References

All the material necessary for successfully aproving the course will be presented during the lectures. As there is no available script, students are strongly recommended to copy the material written on the blackboard during lecture time.

For getting familiar with Description Logics, consult:

  • F. Baader, D. Calvanese, D. McGuinness, D. Nardi, and P. F. Patel-Schneider, editors. The Description Logic Handbook: Theory, Implementation, and Applications. Cambridge University Press, 2003.

  • Franz Baader. Description Logics. In Reasoning Web: Semantic Technologies for Information Systems, 5th International Summer School 2009, volume 5689 of Lecture Notes in Computer Science, pages 1--39. Springer-Verlag, 2009.
For getting familiar with Fuzzy Logic, consult:
  • P. Hajek. Metamathematics of Fuzzy Logic. Springer-Verlag. 1998.

Zuletzt geändert 2017-03-14 Thr von Anni-Yasmin Turhan