Preface Volume 84

AbstractThis volume contains the Proceedings of the 10th Workshop on Logic, Language, Information and Computation (WoLLIC'2003). The Workshop was held in Ouro Preto, Minas Gerais, Brazil from July 29 to August 1, 2003, in the Escola de Minas of the Universidade Federal de Ouro Preto (UFOP).WoLLIC is a series of workshops which started in 1994 with the aim of fostering interdisciplinary research in pure and applied logic. The idea is to provide a forum which is large enough in the number of possible interactions between logic and the sciences related to information and computation, and yet is small enough to allow for concrete and useful interaction among participants. Previous versions were held at: Recife (Pernambuco, Brazil) in 1994 and 1995; Salvador (Bahia, Brazil) in 1996; Fortaleza (Ceará, Brazil) in 1997; São Paulo (Brazil) in 1998; Itatiaia (Rio de Janeiro, Brazil) in 1999; Natal (Rio Grande do Norte) in 2000; Brasília (Distrito Federal, Brazil) in 2001; Rio de Janeiro (Brazil) in 2002.Scientific sponsorship comes from the Interest Group in Pure and Applied Logics (IGPL), the European Association for Logic, Language and Information (FoLLI), the Association for Symbolic Logic (ASL), European Association for Theoretical Computer Science (EATCS), the Sociedade Brasileira de Computação (SBC), and the Sociedade Brasileira de Lógica (SBL).Funding was kindly given by:(i) CNPq (Conselho Nacional de Desenvolvimento Científico e Tecnológico, the scientific and technological development council of the Brazilian Ministério da Ciência e Tecnologia) (grant 450709/2003-5);(ii) CAPES (Fundação Coordenação de Apoio ao Aperfeiçoamento de Pessoal de Nível Superior, a Foundation for the Development of Higher-Education under the Brazilian Ministério da Educação e do Desporto) (grant PAEP0565/03);(iii) FAPEMIG (Fundação de Amparo à Pesquisa do Estado de Minas Gerais, the Minas Gerais state foundation for the support of scientific research);(iv) Escola de Minas da UFOP (Universidade Federal de Ouro Preto).Contributions were received in the form of short papers in all areas related to logic, language, information and computation, including:pure logical systems, proof theory, model theory, algebraic logic, type theory, category theory, constructive mathematics, lambda and combinatorial calculi, program logic and program semantics, logics and models of concurrency, logic and complexity theory, proof complexity, foundations of cryptography (zero-knowledge proofs), descriptive complexity, nonclassical logics, nonmonotonic logic, logic and language, discourse representation, logic and artificial intelligence, automated deduction, foundations of logic programming, logic and computation, and logic engineering.Apart from the contributed papers (15), and the invited talks (5), the programme includes 5 tutorial lectures: 1.Algorithmic Randomness and Derandomizationby Eric Allender (Department of Computer Science, Rutgers, the State University of New Jersey, USA)2.Generalized Quantifiersby Lauri Hella (Department of Mathematics, Statistics and Philosophy, University of Tampere, Finland)3.Implicit computational complexityby Jean-Baptiste Joinet (Preuves-Programmes-Systèmes, Université Paris 7, France)4.Proof search foundations for logic programmingby Dale Miller (INRIA/Futurs/Saclay, and Laboratoire d'Informatique, École Polytechnique, France)5.Iterated theory changeby Hans Rott (Institut für Philosophie, Universität Regensburg, Germany)All papers in the volume were reviewed by the program committee consisting of Mauricio Ayala-Rinóon(Departamento de Matemática, Universidade de Brasília, Brazil)Argimiro Arratia(Depto. Matematicas, Universidad Simon Bolivar, Venezuela)Alessandra Carbone(Institut des Hautes Études Scientifiques, and Université de Paris XII, France)Marcelo Coniglio(Centro de Lógica e Epistemologia, Universidade Estadual de Campinas, Brazil)Gilles Dowek(INRIA, France)Arnaud Fleury(Facoltà di Scienze, Università di Verona, Italy)Dexter Kozen(Cornell University, USA)Maarten Marx(ILLC, Faculty of Science, Universiteit Amsterdam, The Netherlands)Anto˚nio Carlos da Rocha Costa(Escola de Informática, Universidade Católica de Pelotas, Brazil)Dieter Spreen(Fachbereich Mathematik, Theoretische Informatik, Universität Siegen, Germany)Luiz Carlos Pereira(Departamento de Filosofia, PUC-Rio and UFRJ, Brazil)Jouko Väänänen(Department of Mathematics, University of Helsinki, Finland)Renata Wassermann(Departamento de Cie˚ncia da Computação, Instituto de Matemática e Estatística, Universidade de São Paulo, Brazil)The organising committee consisted of Lucília Figueiredo(Departamento de Computação, Universidade Federal de Ouro Preto, Brazil)Fred Ulisses Maranhão(Centro de Informática, Universidade Federal de Pernambuco, Brazil)Anjolina Grisi de Oliveira(Center of Informatics, Universidade Federal de Pernambuco, Brazil)Elaine Pimentel(Departamento de Matemática, Universidade Federal de Minas Gerais, Brazil) (Co-Chair)Ruy de Queiroz(Center of Informatics, Universidade Federal de Pernambuco, Brazil) (Co-Chair)Maria Angela Weiss(Departamento de Matemática, Universidade de São Paulo, Brazil)The volume will be published as volume 84 in the series Electronic Notes in Theoretical Computer Science (ENTCS). This series is published electronically through the facilities of Elsevier B.V. and its auspices. The volumes in the ENTCS series can be accessed at the URLhttp://www.elsevier.nl/locate/entcsA printed version of the current volume has been distributed to the participants at the workshop in Ouro Preto.We are very grateful to the following persons, whose help has been crucial for the success of WoLLIC'2003: Mike Mislove, one of the Managing Editors of the ENTCS series, for his assistance with the use of the ENTCS style files; Thanks are also due to the Department of Mathematics of Universidade Federal de Minas Gerais and the Department of Computing of the Universidade Federal de Ouro Preto, which has provided the logistic support to the organising committee. August 2, 2003Ruy de Queiroz, Elaine Pimentel, Lucilia Figueired