Course on Many-Valued Logics (Autumn 2014)

This page concerns the course `Many-Valued Logics’, taught at the University of Amsterdam from September – October 2014. 

Contents of the page


The course covers the following topics:

  • Basic Logic and Monoidal t-norm Logic.
  • Substructural logics and residuated lattices.
  • Cut elimination and completions.
  • Lukasiewicz logic.

More specifically, this is the content of each single class:

  • September, 1: Introduction, motivations, t-norms and their residua. Section 2.1 (up to Lemma 2.1.13) of the Course Material 1.
  • September, 5: Basic Logic, Residuated lattices, BL-algebras, linearly ordered BL-algebras. Section 2.2 and 2.3 (up to Lemma 2.3.16) of the Course Material 1.
  • September, 8: Lindenbaum-Tarski algebra of BL, algebraic completeness. Monodical t-norm logic, MTL-algebras, standard completeness. The rest of Course Material 1 (excluding Section 2.4) and Course Material 2.
  • September, 12: Ordinal decomposition of BL-algebras. Mostert and Shield Theorem.  Course Material 3.
  • September, 15: Ordinal decomposition of BL-algebras (continued). Algebrizable logics and equivalent algebraic semantics.  Course Material 4.
  • September, 19: Algebrizable logics and equivalent algebraic semantics (continued).  Course Material 4.
  • September, 22: Algebrizable logics and equivalent algebraic semantics (continued): Leibniz operator and implicit characterisations of algebraizability.  Course Material 4.
  • September, 26: Leibniz operator and implicit characterisations of algebraizability (continued).  Course Material 4. Gentzen calculus and the substructural hierarchy. Course Material 5 (to be continued).
  • September, 29: Structural quasi-equations and $N_2$ equations. Residuated frames. Course Material 5 (Continued).
  • October, 3: Analytic quasi-equations, dual frames, and MacNeille completions. Course Material 5 (Continued).
  • October, 9: Atomic conservativity, closing the circle of equivalencies. Course Material 5 (Continued).
  • October, 10: Lukasiewicz logic and MV-algebras. Mundici’s equivalence. Course Material 6.
  • October, 17: The duality between semisimple MV-algebras and Tychonoff spaces. Course Material 7.

Course material

The material needed during the course can be found below.

The homework due during the course can be found below.




  • Classes run from the 1st of September until the 17th of October; there will be 14 classes in total.
  • There are two classes weekly.
  • Due to the high number of participants classrooms will change weekly, will always be updated with the right classrooms.

Grading and homeworks

  • The grading is on the basis of weekly homework assignments, and a written exam at the end of the course.
  • The homework assignments will be made available weekly through this page.
  • The final grade will be determined for 2/3 by homeworks, and for 1/3 by the final exam.
  • In order to pass the course, a score at least 50/100 on the final exam is needed.

More specific information about homework and grading:

  • You are allowed to collaborate on the homework exercises, but you need to acknowledge explicitly with whom you have been collaborating, and write the solutions independently.
  • Deadlines for submission are strict.
  • Homework handed in after the deadline may not be taken into consideration; at the very least, points will be subtracted for late submission.
  • In case you think there is a problem with one of the exercises, contact the lecturer immediately.

Course Description

Many-valued logics are logical systems in which the truth values may be more than just “absolutely true” and “absolutely false”. This simple loosening opens the door to a large number of possible formalisms. The main methods of investigation are algebraic, although in the recent years the proof theory of many-valued logics has had a remarkable development.

This course will address a number of questions regarding classification, expressivity, and algebraic aspects of many-valued logics. Algebraic structures as Monoidal t-norm based algebras, MV-algebras, and residuated lattices will be introduced and studied during the course.

The course will cover seclected chapters of the following books.

  • P. Hájek, ‘Metamathematics of Fuzzy Logic‘, Trends in Logic, Vol. 4 Springer, 1998.
  • P. Cintula, P. Hájek, C. Noguera (Editors). ‘Handbook of Mathematical Fuzzy Logic‘ – Volume 1 and 2. Volumes 37 and 38 of Studies in Logic, Mathematical Logic and Foundations. College Publications, London, 2011
  • R. L. O. Cignoli, I. M. L. D’Ottaviano e D. Mundici, ‘Algebraic Foundations of Many-Valued Reasoning‘, Trends in Logic, Vol. 7 Springer, 2000
  • D. Mundici. ‘Advanced Lukasiewicz calculus and MV-algebras‘, Trends in Logic, Vol. 35 Springer, 2011.


It is assumed that students entering this class possess

  • Some mathematical maturity.
  • Familiarity with the basic theory of propositional and first order (classical) logic.

Basic knowledge of general algebra, topology and category theory will be handy but not necessary.


Comments, complaints, questions: mail Luca Spada

Algebra|Coalgebra seminar

Starting from October 2013 I am organising the Algebra|Coalgebra seminar at the ILLC.  The webpage of the seminar are here.  See you there!

ADAMS project will start soon (1st of August 2013 — 31th July 2015)

Starting from the 1st of August 2013, I will be on leave from the University of Salerno.  For two years form this date, I will be affiliated at the Institute for Logic, Language, and Computation of the University van Amsterdam.

This opportunity is funded by a Marie Curie scholarship awarded to the research project “ADAMS” (A Dual Approach to Many-valued Semantics).