## Robert Kowalski ## Professor Emeritus and Senior Research Fellow ## Department of Computing Imperial College London 180 Queen's Gate, London SW7 2BZ, UK. Email: rak at doc.ic.ac.uk ## Please note that I am no longer accepting research students. |

## Curriculum Vitae

## A Short Story of My Life and Work

## Computational Logic and Human Thinking:
How to be Artificially Intelligent

This book, published in July 2011 by Cambridge University Press, presents the principles of Computational Logic, so that they can be applied in everyday life. I have written the main part of the book informally, both to reach a wider audience and to demonstrate that the enhanced logic is indeed useful for human thinking. However, I have also included a number of additional, more formal chapters for the more advanced reader.

I gave a short course based on the book at the Third International ALP/GULP Spring School on Computational Logic in Bertinoro, Italy, 10-15 April 2011. Here is a link to the slides.

I have also given a longer, 14 lecture course at the University of Kyoto, 3 October - 12 December 2012. (Each lecture is one and a half hours.) Here is a link to the slides for the complete set of lectures. If you are teaching a course, and would like solutions to the homework, please email me at rak at doc dot ic dot ac dot uk.

Jacinto Davila has also used a draft of this book for a course at Universidad de Los Andes, Venezuela. Here is a link to his Spanish translation of an earlier draft.

## Logic for Problem Solving

The book, originally published by North-Holland in 1979, is now out of print.

- Chapter 0 Table of Contents 290KB
- Chapter 1 Introduction 611KB
- Chapter 2 Representation in Clausal Form 713KB
- Chapter 3 Top-down and Bottom-up Proof Procedures 626 KB
- Chapter 4 Horn Clause Problem Solving 866K
- Chapter 5 The Procedural Interpretation of Horn Clauses 856
- Chapter 6 Plan Formation and the Frame Problem 393KB
- Chapter 7 Resolution 344KB
- Chapter 8 The Connection Graph Proof Procedure 426KB
- Chapter 9 Global Problem Solving Strategies 393KB
- Chapter 10 Comparison of Clausal Form with Standard Form 469KB
- Chapter 11 If-and-only-if 398KB
- Chapter 12 Formalisation of Provability 449KB
- Chapter 13 Logic, Change and Contradiction 344KB
- References 490KB
- Index 288KB

## New paper: Towards a Logic-Based Framework for Computing with Fariba Sadri, June 2013

In this paper we propose a logic-based, framework for Computing, inspired by artificial intelligence, but scaled down for practical database and programming applications. Computation in the framework is viewed as the task of generating a sequence of state transitions, with the purpose of making an agent's goals all true. States are represented by sets of atomic sentences (or facts), representing the values of program variables, tuples in a coordination language, facts in relational databases, or Herbrand models.

In the model-theoretic semantics, the entire sequence of states and events is contained in a single model-theoretic structure, by associating time stamps with facts. But in the operational semantics, facts are updated destructively, without time stamps. We show that the model generated by destructive updates is identical to the model generated by reasoning with facts containing time stamps. We also extend the model with intentional predicates and composite event predicates defined by logic programs containing conditions in first-order logic, which are used to query the current state.

## WUENIC:

I have been working with WHO and UNICEF since 2009, helping to develop, implement and deploy a set of logical rules to assist in estimating global, country by country, infant immunization coverage . The problem is to reconcile inconsistencies when different sources of data conflict - for example when government reported data is inconsistent with survey data. The purpose of the logical rules is to make the reconciliation and estimation process more transparent and more consistent.

The rules have been implemented in XSB Prolog as a purely declarative logic program, and have been used to assist in making the estimates in 2010, 2011 and 2012 for each of the preceding years. In addition to helping to ensure transparency and consistency, the Prolog implementation has also proved useful in providing detailed documentation of the rationale for each of the estimates.

There are two articles describing our work. The first , published in the online journal PLOS-ONE, describes our work for a general audience with little or no computing background. The second , presented at JURISIN 2011, describes the work for a more academic audience and compares it with previous work on the logical formalisation of the British Nationality Act.

## Selected bibliography:

Early papers on theorem-proving, logic programming and knowledge representation:

- Kowalski, R. and Kuehner, D., Linear Resolution with Selection Function In Artificial Intelligence, Vol. 2, 1971, pp. 227-60.
  Reprinted in Anthology of Automated Theorem-Proving Papers, Vol. 2, Springer-Verlag, 1983, pp. 542-577.

- Kowalski, R., Predicate Logic as Programming Language In Proceedings IFIP Congress, Stockholm, North Holland Publishing Co., 1974, pp. 569-574. Reprinted in Computers for Artificial Intelligence Applications, (eds. Wah, B. and Li, G.-J.), IEEE Computer Society Press, Los Angeles, 1986, pp. 68-73.

- Kowalski, R. A Proof Procedure Using Connection Graphs
  In JACM Vol. 22, No. 4, 1975, pp. 572-595.

- van Emden, M. and Kowalski, R. The Semantics of Predicate Logic as a Programming Language In JACM , Vol. 23, No. 4, 1976, pp. 733-742.

- Deliyanni, A. and Kowalski, R. Logic and Semantic Networks
  In CACM, Vol. 22, No. 3, 1979, pp. 184-192.

- Kowalski, R. Algorithm = Logic + Control
  In CACM, Vol. 22, No. 7, 1979, pp. 424-436. Reprinted in Programming Languages: A Grand Tour, Third Edition, (ed. E. Horwitz), Computer Science Press, Maryland, 1986, pp. 480-492.

- Kowalski, R. The Relationship between Logic Programming and Logic Specification In Phil. Trans. R. Soc. Lond. A, Vol 312, 1984, pp. 345-361.

- Kowalski, R. The Limitations of Logic In Proceedings of ACM Computer Science Conference, 1986, pp 7-13. Revised version in Proceedings of SEAS, Heidelberg, 1986, pp. 1-13. Also in Knowledge Base Management Systems, (eds. C. Thanos and J. W. Schmidt), Springer-Verlag, pp. 477-489.

- Kowalski, R., Sadri, F. and Soper, P. Integrity Checking in Deductive Databases In Proceedings of VLDB, Morgan Kaufmann, Los Altos, Ca., 1987, pp. 61-69.

- Kowalski, R. The Early Years of Logic Programming In CACM, 1988, Vol. 31, No. 1, pp. 38-43.

Legal reasoning and argumentation

- Sergot, M., Sadri, F., Kowalski, R., Kriwaczek, F., Hammond, P., and Cory,T. The British Nationality Act as a Logic Program
  In CACM, Vol. 29, No. 5, 1986, pp. 370-386.

- Kowalski, R. The Treatment of Negation in Logic Programs for Representing Legislation
  In Proceedings of Second International Conference on AI and Law, (ed. E. Rissland) Vancouver, Canada, ACM Press, 1989, pp. 11-15.

- R. Kowalski, Legislation as Logic Programs
  In: Logic Programming in Action (eds. G. Comyn , N. E. Fuchs, M. J. Ratcliffe), Springer Verlag, pages 203-230 (1992)

- R. Kowalski, F. Toni, Argument and Reconciliation ,
  In: International Symposium on Fifth Generation Computer Systems '94, Workshop on Legal Reasoning, Tokyo, pages 9-16 (1994)

- R. Kowalski, F. Toni, Abstract Argumentation ,
  In: Artificial Intelligence and Law Journal 4(3-4), Special Issue on Logical Models of Argumentation, H. Prakken and G. Sartor, eds., Kluwer Academic Publishers, pages 275-296 (1996)

Metalogic programming

- Kowalski, R. and Kim, J. S. A Metalogic Programming Approach to Multi-Agent Knowledge and Belief
  In Artificial Intelligence and Mathematical Theory of Computation (ed. V. Lifschitz), Academic Press, 1991, pp. 231-246.

- R. Kowalski, Logic without Model Theory ,
  In: What is a logical system?, D. Gabbay ed., Oxford University Press (1995)

Event Calculus

- Kowalski, R. and Sergot, M. A Logic-based Calculus of Events
  In New Generation Computing, Vol. 4, No.1, February 1986, pp. 67-95. Also in Knowledge Base Management-Systems, (eds. C. Thanos and J. W. Schmidt), Springer-Verlag, pp. 23-51. Also in The Language of Time: A Reader (eds. Inderjeet Mani, J. Pustejovsky, and R. Gaizauskas) Oxford University Press. 2005.

- Kowalski, R. Database Updates in the Event Calculus
  In Journal of Logic Programming, 1992, Vol. 12, No. 162, pp. 121-146.

- R. Kowalski, F. Sadri, The situation calculus and event calculus compared , In: Proc. International Logic Programming Symposium, ILPS'94 (1994)

- F. Sadri, R. Kowalski, Variants of the event calculus , In: Proc. International Conference on Logic Programming, L. Sterling, ed., MIT Press (1995)

- R. Kowalski, F. Sadri, Reconciling the Situation Calculus and Event Calculus , In: Journal of Logic Programming Vol. 31, pages 39-58, Special Issue on Reasoning about Action and Change (1997)

Abductive Logic Programming

- K. Eshghi and R. Kowalski, Abduction Compared with Negation as Failure, Sixth International Conference on Logic Programming (1989)

- A.C. Kakas, R. Kowalski, F. Toni, Abductive logic programming ,
  In: Journal of Logic and Computation 2(6) pages 719-770 (1992)

- R. Kowalski, F. Toni, G. Wetzel,
  Towards a declarative and efficient glass-box CLP language ,
  In: Proc. of Logic Programming Workshop WLP'94, N. Fuchs and G. Gottlob, eds., Zurich (1994)

- F. Toni, R. Kowalski, Reduction of abductive logic programs to normal logic programs , In: Proc. International Conference on Logic Programming, L. Sterling, ed., MIT Press, pages 367-381 (1995)

- G. Wetzel, R. Kowalski, F. Toni, A Theorem-Proving Approach to CLP, In: Proc. of Logic Programming Workshop WLP'95, A. Krall and U. Geske, eds., Vienna (1995)

- R. Kowalski, G. Wetzel, F. Toni, A Unifying Framework for ALP, CLP and SQO , Technical Report, Department of Computing, Imperial College, London (1996)

- Fung, T.H. and Kowalski, R. The IFF Proof Procedure for Abductive Logic Programming. Journal of Logic Programming, 1997.

- A. C. Kakas, R. Kowalski, F. Toni, The Role of Abduction in Logic Programming , In: Handbook of Logic in Artificial Intelligence and Logic Programming 5, pages 235-324, D.M. Gabbay, C.J. Hogger and J.A. Robinson eds., Oxford University Press (1998)

- R.A. Kowalski, F. Toni, G. Wetzel, Executing Suspended Logic Programs , In: Fundamenta Informatica 34 (3) (1998)

From Abduction to Argumentation

- A. Bondarenko, F. Toni, R. Kowalski, An Assumption-based Framework for Non-monotonic Reasoning , In: Proc. 2nd International Workshop on Logic Programming and Non-monotonic Reasoning, L.M. Pereira and A. Nerode, eds., pages 171-189 (1993)

- F. Toni, R. Kowalski, An argumentation-theoretic approach to logic program transformation , In: Proc. LOPSTR'95, International Workshop on Logic Program Synthesis and Transformation, M. Proietti ed., LNCS 1048, Springer Verlag, pages 61-75 (1995)

- P.M. Dung, R. Kowalski, F. Toni, Synthesis of proof procedures for default reasoning , In: Proc. LOPSTR'96, International Workshop on Logic Program Synthesis and Transformation, J. Gallagher ed., LNCS 1207, Springer Verlag, pages 313-324 (1996)

- A. Bondarenko, P.M. Dung, R. Kowalski, F. Toni, An abstract, argumentation-theoretic approach to default reasoning, In: Artificial Intelligence 93(1-2) pages 63-101 (1997)

- Dung, P. M., Kowalski, R., and Toni, F. Dialectic proof procedures for assumption-based, admissible argumentation , Journal of Artificial Intelligence 170(2), February 2006, pp. 114-159

- Dung, P. M., Kowalski, R., and Toni, F. Assumption-Based Argumentation. In Argumentation in Artificial Intelligence edited by I. Rahwan and G. Simari) Springer, 2009.

Intelligent Agents

- Kowalski, R., Logic-based Open Systems, Department of Computing, Imperial College, 1985. In Representation and Reasoning. Jakob ph. Hoepelman (Hg.) Max Niemeyer Verlag, Tübingen 1988, pp. 125-134.

- R. Kowalski, Using metalogic to reconcile reactive with rational agents , In: Meta-Logics and Logic Programming (K. Apt and F. Turini, eds.), MIT Press (1995)

- R. Kowalski, F. Sadri, Towards a unified agent architecture that combines rationality with reactivity, In: Proc. International Workshop on Logic in Databases, San Miniato, Italy, Springer- Verlag, LNCS 1154 (1996)

- R. Kowalski, F. Sadri, An Agent Architecture that Unifies Rationality with Reactivity , Department of Computing, Imperial College (1997)

- R. Kowalski, F. Sadri, From Logic Programming towards Multi-agent Systems , In: Annals of Mathematics and Artificial Intelligence Volume 25, pages 391-419 (1999)

- R. Kowalski, Artificial intelligence and the Natural World , Cognitive Processing, Volume 2 (2001)

- R. Kowalski, The Logical Way to be Artificially Intelligent In Proceedings of CLIMA V (eds. F. Toni and P. Torroni) Springer Verlag, LNAI, 2006, pp. 1-22

- R. Kowalski, F. Sadri,Integrating Logic Programming and Production Systems in Abductive Logic Programming Agents, In Web Reasoning and Rule Systems (eds. A. Polleres and T. Swift) Springer, LNCS 5837. 2009.

- R. Kowalski, F. Sadri An Agent Language with Destructive Assignment and Model-theoretic Semantics, In CLIMA XI - Computational Logic in Multi- Agent Systems (eds. J. Dix, G. Governatori, W. Jamroga and J. Leite) Springer, 2010.

- R. Kowalski, F. Sadri Abductive Logic Programming Agents with Destructive Databases, In Annals of Mathematics and Artificial Intelligence, 2011.

- R. Kowalski, Artificial Intelligence and Human Thinking, IJCAI, 2011.

- R. Kowalski and F. Sadri, Teleo-Reactive Abductive Logic Programs In Festschrift for Marek Sergot.(eds: Alexander Artikis, Robert Craven, Nihan Kesim, Babak Sadighi, and Kostas Stathis), Springer, 2012.

- R. Kowalski and F. Sadri, A Logic-Based Framework for Reactive Systems In Procedings of RuleML 2012.

Miscellaneous papers

- R. Kowalski, Logic Programming MIT Encyclopaedia of Cognitive Science (eds. R A Wilson and F C Keil) MIT Press (1999)

- R. Kowalski, Logic Programming and the Real World Logic Programming Newsletter. January 2001

- R. Kowalski, Directions for Logic Programming Computational Logic: Logic Programming and Beyond (eds. A C Kakas and F Sadri) Springer, 2002, 26-32.

- R. Kowalski, A logic-based model for conflict resolution April 2003.

- R. Kowalski, Logic and Modularity April 2005.

- R. Kowalski, Computational Logic as a Dual Process Model of Thought February 2006.

- R.A. Kowalski, Computational Logic in an Object-Oriented World In: Reasoning, Action and Interaction in AI Theories and Systems - Festschrift in Honor of Luigia Carlucci Aiello. (eds. O. Stock, M. Schaerf) Springer Verlag, LNAI, 2006.

- R. Kowalski, From Mathematical Logic, to Natural Language, Artificial Intelligence, and Human Thinking Andrzej Mostowski and Foundational Studies (Eds. A. Ehrenfeucht, V.W. Marek and M. Srebrny) IOS Press, 2008

- R. Kowalski, Time to think like a Computer , New Scientist 3 December 2011

Updated 27 August 2013