This volume contains finalized versions of papers presented at an international workshop on extensions of logic programming, held at the Seminar for Natural Language Systems at the University of Tubingen in December 1989. Several recent extensions of definite Horn clause programming, especially those with a proof-theoretic background, have much in common. One common thread is a new emphasis on hypothetical reasoning, which is typically inspired by Gentzen-style sequent or natural deduction systems. This is not only of theoretical significance, but also bears upon computational issues. It was...

This volume contains papers presented at the secondinternational workshop on extensions of logic programming, which was held at the Swedish Institute of Computer Science, Stockhom, January 27-29, 1991.The 12 papers describe and discuss several approaches toextensions of logic programming languages such as PROLOG, aswell as connections between logic programming and functionalprogramming, theoretical foundations of extensions, applications, and programming methodologies.The first workshop in this series was held in T}bingen in1989 and its proceedings areavailable as LNCS 475. Thethird workshop...

Proof theory has long been established as a basic discipline of mathematical logic. It has recently become increasingly relevant to computer science. The - ductive apparatus provided by proof theory has proved useful for metatheoretical purposes as well as for practical applications. Thus it seemed to us most natural to bring researchers together to assess both the role proof theory already plays in computer science and the role it might play in the future. The form of a Dagstuhl seminar is most suitable for purposes like this, as Schloss Dagstuhl provides a very convenient and stimulating...

This book constitutes the refereed proceedings of the 5th International Workshop on Extensions of Logic Programming, ELP '96, held in Leipzig, Germany in March 1996.
The 18 full papers included were carefully selected by the program committee and are presented together with three invited papers. Among the topics addressed in this book are categorical logic programming, correctness of logic programs, functional-logic languages, implementation issues, linear logic programming, nonmonotonic reasoning, and proof search.

This open access book is the first ever collection of Karl Popper's writings on deductive logic. Karl R. Popper (1902-1994) was one of the most influential philosophers of the 20th century. His philosophy of science ("falsificationism") and his social and political philosophy ("open society") have been widely discussed way beyond academic philosophy. What is not so well known is that Popper also produced a considerable work on the foundations of deductive logic, most of it published at the end of the 1940s as articles at scattered places. This little-known work deserves to be known better,...