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Homepage of Karl Schlechta

Karl Schlechta

Professor of Computer Science (Retired)

Laboratoire d'Informatique Fondamentale de Marseille

Aix-Marseille Universite

(formerly Universite de Provence)

Marseille, France


GOOGLE CONVERSION HAS MADE A HORRIBLE MESS OF MY WEB PAGE,

THIS WILL TAKE TIME TO CORRECT - SORRY


Address etc.

TO LIMIT SPAMS, "@" HAS BEEN REPLACED BY "*"

schcsg*gmail.com

Karl Schlechta Koppeweg 24 D-97833 Frammersbach Germany

Research

Subjects

    • Nonmonotonic logic

    • Theory revision and update

    • Counterfactual conditionals

Formal work

    • Semantics and completeness proofs

    • Development of new concepts

    • Development of new proof techniques



But

There is still a lot of research to do, terra incognita is vast:

"Das Innere der Leberworscht ist noch gaenzlich unerforscht!"


CV

7.1.1948 born in Kronberg/Taunus (Germany)

1980 Diplom in mathematics and psychology, Heidelberg

1980-1984 software development in industry (Fortran, Pascal, real-time software) in Karlsruhe and Berlin

1984-1987 assistant research position at the Institute for Mathematics, Freie Universitaet Berlin

1988 Promotion (PhD) at the institute for mathematics,

Freie Universitaet Berlin,

thesis in the field of set theory, "A Model of CH without Souslin Trees and without Kurepa Trees in ccc-Extensions"

1988-1991 research position at the Institute for Computer Science, University of Hamburg, and IBM Stuttgart (LILOG project)

1992 invited scientist at IBM Stuttgart

1992 Habilitation at the Institute for Computer Science, University of Hamburg, titel of thesis : "Results on Non-Monotonic Logics"

1993 invited scientist at the German Research Center for Artificial Intelligence (DFKI) at Saarbruecken and at the Gesellschaft fuer Mathematik und Datenverarbeitung, Bonn

1993-2014 Professor for Computer Science, Marseille, France

1/9/00-31/8/02 DR CNRS (delegation)

31/8/2014 Retired

Varia and personal stuff (in disorder)

Erdos Number 2 (P.Erdos -> M.Magidor -> K.Schlechta)

Provence is beautiful. If you are in the area, don't forget sightseeing.

Student days


List of Publications



Most new articles are accessible via arXiv.org, under the same title,

in preliminary versions.

In addition, as yet unpublished work may also be found in arXiv.org.



(Dec. 26, 2022)



Books

=====



2022



[Sch22] Karl Schlechta:

Truth and Knowledge,

College Publications, Rickmansworth, UK

Series Studies in Logic and Argumentation

ISBN 978-1-84890-403-3



2018



[Sch18] Karl Schlechta:

"Formal Methods for Nonmonotonic

and Related Logics"

Springer, Heidelberg

(graduate level textbook)


Vol 1: Preference and Size

p. 1-336

ISBN 978-3-319-89652-6

[Sch18a]


Vol 2: Theory Revision, Inheritance, and Various

Abstract Properties

p. 337-817

ISBN 978-3-319-89649-6

[Sch18b]



2016



[GS16] Dov Gabbay, Karl Schlechta:

"A new perspective on non-monotonic

logics"

Springer, Heidelberg, ISBN 978-331-946-8150

Nov. 14, 2016



2011



[GS10] Dov Gabbay, Karl Schlechta:

"Conditionals and modularity in

general logics"

Springer, Heidelberg, August 2011,

ISBN 978-3-642-19067-4,

a preliminary version is accessible via

arXiv.org, same title



2009



[GS09f] Dov Gabbay, Karl Schlechta:

"Logical tools for handling change in

agent-based systems"

Springer, ISBN 978-3642044069

a (condensed) preliminary version is accessible via

arXiv.org, same title



2004



[Sch04] Karl Schlechta: Coherent systems

Vol. 2 of the Series:

Studies in Logic and Practical Reasoning,

Elsevier, Amsterdam,

Sept. 2004,

pp. 468,

ISBN 0-444-51789-8



1997



[Sch97-2] K.Schlechta : "Nonmonotonic logics - Basic Concepts,

Results, and Techniques"

Springer Lecture Notes series, LNAI 1187, Jan. 1997,

243pp



Articles in journals

====================



2010



[GS09c] D.Gabbay, K.Schlechta: "Semantic Interpolation"

Journal of Applied Non-classical Logics,

Vol 20/4, 2010, pp. 345-371



2009



[GS09a] D.Gabbay, K.Schlechta: "Size and Logic"

Review of Symbolic Logic,

Vol. 2, No. 2, pp. 396-413, 2009




[GS09b] D.Gabbay, K.Schlechta: "Independence - revision and defaults",

Studia Logica (2009) 92, pp. 381-394,




[GS08b] D.Gabbay, K.Schlechta: "Reactive preferential

structures and nonmonotonic consequence",

Review of Symbolic Logic,

Vol. 2, No. 2, pp. 414-450, 2009




[GS08h] D.Gabbay, K.Schlechta: "A comment on work by

Booth and co-authors",

Studia Logica, 2010, 94:403-432



2008



[GS08a] D.Gabbay, K.Schlechta: "Cumulativity without

closure of the domain under finite unions",

Review of Symbolic Logic,

1 (3): 372-392, 2008



[GS08d] D.Gabbay, K.Schlechta: "A theory of hierarchical

consequence and conditionals",

Journal of Logic, Language and Information,

19:1, 3-32, 2010



[GS08e] D.Gabbay, K.Schlechta: "Defeasible inheritance

systems and reactive diagrams",

Logic Journal of the IGPL,

17:1-54, 2009



[GS08c] D.Gabbay, K.Schlechta: "Roadmap for preferential

logics",

Journal of applied nonclassical logics,

Vol. 19/1, pp. 43-95, 2009,



2001



[LMS01] D.Lehmann, M.Magidor, K.Schlechta: "Distance

Semantics for Belief Revision",

Journal of Symbolic Logic, Vol.66, No. 1, March 2001,

p. 295-317



[SD01] K.Schlechta, J.Dix: "Explaining updates by minimal

sums",

Theoretical Computer Science, 266 (2001), pp. 819-838



2000



[Sch00-1] K.Schlechta: "New techniques and completeness results

for preferential structures"

Journal of Symbolic Logic, Vol. 65, No. 2, pp. 719-746,

June 2000



[SGMRT00] K.Schlechta, L.Gourmelen, S.Motre, O.Rolland,

B.Tahar: "A new approach to preferential

structures", Fundamenta Informaticae, Vol. 42,

No. 3-4, pp. 391-410, April-May 2000



[Sch00-2] K.Schlechta: "Unrestricted preferential structures",

Journal of Logic and Computation,

Vol.10, No.4, pp.573-581, 2000



1999



[BLS99] S.Berger, D.Lehmann, K.Schlechta: "Preferred

History Semantics for Iterated Updates",

Journal of Logic and Computation,

Vol.9, No.6, pp.817-833, 1999



[Sch99] K.Schlechta: "A topological construction of a

non-smooth model of cumulativity"

Journal of Logic and Computation,

Vol.9, No.4, pp.457-462, 1999



[ALS99] L.Audibert, C.Lhoussaine, K.Schlechta: "Distance

based revision of preferential logics"

Logic Journal of the Interest Group

in Pure and Applied Logics (1999), Vol. 7, No. 4, July 1999,

pp. 429-446



1997



[Sch97-1] K.Schlechta : "A Reduction of the Theory of Confirmation

to the Notions of Distance and Measure",

Logic Journal of the Interest Group in Pure and Applied

Logics, Vol.5, No.1, pp.49-64, 1997



[Sch97-3] K.Schlechta : "Symmetrical Theory Revision",

(Non-prioritized belief revision based on

distances between models),

Theoria, Vol. 63, Part 1-2, pp. 34-53, 1997

(appeared in 1999)



[BGHPSW97] D.Bellot, C.Godefroid, P.Han, J.P.Prost, K.Schlechta,

E.Wurbel:

"A semantical approach to the concept of screened

revision",

Theoria, Vol. 63, Part 1-2, pp. 24-33, 1997

(appeared in 1999)



[Sch97-4] K.Schlechta: "Filters and Partial Orders",

Journal of the Interest Group in Pure and Applied

Logics, Vol. 5, No. 5, p. 753-772, 1997



1996



[Sch96-1] K.Schlechta : "Some Completeness Results for Stoppered

and Ranked Classical Preferential Models",

Journal of Logic and Computation, Oxford,

Vol. 6, No. 4, pp. 599-622, 1996



[Sch96-3] K.Schlechta : "Completeness and Incompleteness for

Plausibility Logic",

Journal of Logic, Language and Information, 5:2, 1996,

p.177-192, Kluwer, Dordrecht



[Sch96-2] K.Schlechta : "A Two-Stage Approach to First Order

Default Reasoning",

Fundamenta Informaticae, Vol. 28, No. 3-4, pp. 377-402,

1996



1995



[Sch95-1] K.Schlechta : "Defaults as Generalized Quantifiers",

Journal of Logic and Computation, Oxford,

Vol.5, No.4, p.473-494, 1995



[Sch95-2] K.Schlechta : "Logic, Topology, and Integration",

Journal of Automated Reasoning, 14:353-381, 1995, Kluwer



[Sch95-3] K.Schlechta : "Preferential Choice Representation

Theorems for Branching Time Structures"

Journal of Logic and Computation, Oxford,

Vol.5, pp.783-800, 1995



[Sch95-5] K.Schlechta : "Some Completeness Results for

Propositional Conditional Logics",

Bulletin of the IGPL, Vol.3, No.1, March 1995,

p.111-115



1994



[SM94] K.Schlechta, D.Makinson : "Local and Global Metrics

for the Semantics of Counterfactual Conditionals",

Journal of Applied Non-Classical Logics, Vol.4, No.2,

pp.129-140, Hermes, Paris, 1994



1993



[Sch93] K.Schlechta : "Directly Sceptical Inheritance Cannot

Capture the Intersection of Extensions",

Journal of Logic and Computation, Oxford,

Vol.3, No.5 (1993), p. 455-467



1992



[Sch92] K.Schlechta : "Some Results on Classical Preferential

Models",

Journal of Logic and Computation, Oxford,

Vol.2, No.6 (1992), p. 675-686



1991



[MS91] D.Makinson, K.Schlechta : "Floating Conclusions and

Zombie Paths",

(On principles and problems of defeasible inheritance),

Artificial Intelligence 48 (1991), p. 199-209



[Sch91-1] K.Schlechta : "Theory Revision and Probability",

Notre Dame Journal of Formal Logic 32, No.2 (1991),

p. 307-319



[Sch91-2] K.Schlechta : "Results on Infinite Extensions",

Journal of Applied Non-Classical Logics, Hermes,

Paris, Vol. 1, No. 1 (1991), p. 65-72



1990



[JS90] R.B.Jensen, K.Schlechta : "Results on the Generic Kurepa

Hypothesis",

Archive for Mathematical Logic, Vol. 30 (1990), p. 13-27



Articles in books



2014



[Sch14] K.Schlechta: "Non-monotonic logic: preferential versus

algebraic semantics"

in: "David Makinson on classical methods for

non-classical problems", S.O.Hansson Ed.,

Springer, Heidelberg, 2014



2006



[Sch07] K.Schlechta: "Nonmonotonic logics - a preferential

approach",

in: "Handbook of the history of logic", vol.8:

"The many-valued and non-monotonic turn in logic",

D.Gabbay, J.Woods eds., Elsevier, 2007, pp. 451-516



2002



[Sch02-1] K.Schlechta : "Consid‚rations subjectives sur la

s‚mantique de la r‚vision des th‚ories" (trad.

P.Livet),

in "R‚vision des croyances", P.Livet ed.,

HermŠs/Lavoisier, Paris, 2002,

p. 167-180



1995



[Sch95-4] K.Schlechta : "Some Completeness Results for Classical

Preferential Models",

in "Logic, Action, and Information", A.Fuhrmann,

H.Rott eds., De Gruyter, Berlin/New York, 1995/96,

p. 229-237



Articles in proceedings of conferences

======================================



1999



[DS99] J.Dix, K.Schlechta: Explaining updates by minimal

sums,

19th. Intern. Conf. on Foundations of Software

Technology and Theoretical Computer Science,

13-15 Dec. 1999, IIT Campus, Chennai, India,

Springer LNCS 1738



1998



[ALS99] L.Audibert, C.Lhoussaine, K.Schlechta: "Distance based

revision of preferential logics", in

Belief Revision Workshop of KR98 (Knowledge Representation),

Trento, Italy, 1998 (electronic proceedings)



[AS98] L.Audibert, K.Schlechta: Defeasible inheritance and

reference classes, to appear in the Proceeding of the

Belief Revision Workshop of KR98 (Knowledge Representation),

Trento, Italy, 1998, Hans Rott, Maryanne Williams eds.



1996



[SLM96] K.Schlechta, D.Lehmann, M.Magidor : "Distance Semantics

for Belief Revision", in

Proceedings of: Theoretical Aspects of Rationality and

Knowledge, Tark VI, 1996, ed. Y.Shoham, Morgan Kaufmann,

San Francisco, 1996, p. 137-145



1995



[Sch95-6] K.Schlechta : "A Two-Stage Approach to First Order Default

Reasoning", in

"Symbolic and Quantitative Approaches to Reasoning and

Uncertainty" (Proceedings of ECSQARU-95, Fribourg, Suisse,

July 1995), C.Froidevaux, J.Kohlas eds., p. 379-386,

Springer Lecture Notes in AI, 1995



[Sch95-7] K.Schlechta : "A Reduction of the Theory of Confirmation

to the Notions of Distance and Measure", in

"Symbolic and Quantitative Approaches to Reasoning and

Uncertainty" (Proceedings of ECSQARU-95, Fribourg, Suisse,

July 1995), C.Froidevaux, J.Kohlas eds., p. 387-394,

Springer Lecture Notes in AI, 1995



[Sch95-8] K.Schlechta : "A Reduction of the Theory of Confirmation to

the Notions of Distance and Measure",

10th International Congress of Logic, Methodology and

Philosophy of Science, Firenze (Italy), August 1995



1993



[BS93] F.Baader, K.Schlechta : "A Semantics for Open Normal

Defaults via a Modified Preferential Approach", in

"Symbolic and Quantitative Approaches to Reasoning and

Uncertainty" (Proceedings of ECSQARU-93, Granada, Spain,

November 1993), M.Clarke, R.Kruse, S.Moral eds., p. 9-16,

Springer Lecture Notes in AI, 1993



1991



[Sch91-3] K.Schlechta : "Some Results on Theory Revision",

"The Logic of Theory Change", A. Fuhrmann, M. Morreau

eds., Springer Verlag 1991, p.72-92



[BMS91-1] G.Brewka, D.Makinson, K.Schlechta : "JTMS and Logic

Programming",

"Proceedings International Workshop on Non-Monotonic

Reasoning and Logic Programming",

Washington, Juli 1991



[BMS91-2] G.Brewka, D.Makinson, K.Schlechta : "Cumulative Inference

Relations for JTMS and Logic Programming",

"Nonmonotonic and Inductive Logic", J.Dix, K.P.Jantke,

P.Schmitt eds., Springer Verlag 1991, p.1-12



1990



[Sch90] K.Schlechta : "Semantics for Defeasible Inheritance",

Proceedings ECAI 90, L.G.Aiello ed., London 1990,

p.594-597



1989



[Sch89-1] K.Schlechta : "Defeasible Inheritance : Coherence

Properties and Semantics",

"Proceedings of Tubingen Workshop on Semantic Networks

and Non-Monotonic Reasoning", M.Morreau ed.,

SNS-Report 89-48, Seminar fur naturlichsprachliche

Systeme, Universitaet Tubingen, (1989)



[Sch89-2] K.Schlechta : "Directly Sceptical Inheritance cannot

Capture the Intersection of Extensions",

"Proceedings Workshop Non-Monotonic Reasoning 1989",

G.Brewka, H.Freitag eds.,

GMD-Report 443, Arbeitspapiere der Gesellschaft fur

Mathematik und Datenverarbeitung (1989)



1988



[Sch88-1] K.Schlechta : "Remarks on Shoham's Temporal Logic",

Proceedings der GWAI 88, W.Hoeppner ed.,

Springer Verlag 1988 (Informatik Fachberichte Nr. 181)



[Sch88-2] K.Schlechta : "Remarks on Consistency and Completeness of

Circumscription"

Proceedings der GWAI 88, W.Hoeppner ed.,

Springer Verlag 1988 (Informatik Fachberichte Nr. 181)