The volume contains 2 invited addresses and 21 selectedpapers covering such topics as:- Logical foundations of logic programming andknowledge-based systems,- Automated theorem proving,- Partial and dynamic logics,- Systems of nonmonotonic reasoning,- Temporal and epistemic logics,- Belief revision.

A modal theory of arrows. Arrow logics I.- Knowledge without modality: A simplified framework for chronological ignorance.- Design complete sequential calculus for continuous fixpoint temporal logic.- Logical omniscience and classical logic.- Weak implication: Theory and applications.- Deriving inference rules for terminological logics.- Linear proofs and linear logic.- Relevance and revision.- Modellings for belief change: Base contraction, multiple contraction, and epistemic entrenchment (preliminary report).- A framework for default logics.- A conceptualization of preferences in non-monotonic proof theory.- Reasoning with defeasible arguments: Examples and applications.- About deductive generalization.- Transition systems and dynamic semantics.- Declarative semantics for inconsistent database programs.- Tableau-based theorem proving and synthesis of ?-terms in the intuitionistic logic.- A constructive type system based on data terms.- An ordered resolution and paramodulation calculus for finite many-valued logics.- An efficient constraint language for polymorphic order-sorted resolution.- Default theory for Well Founded Semantics with explicit negation.- Computing answers for disjunctive logic programs.- Expanding logic programs.- Disjunctive logic programming, constructivity and strong negation.