Algebraic aspects of the relational knowledge representation: Modal relation algebras -- A logic for memory -- Actions with preconditions and postconditions -- Testclasses and closed world assumptions for non-horn theories -- Reasoning with negative information, II: Hard negation, strong negation and logic programs -- Lindenbaum-algebraic semantics of logic programs -- Conditional logics and cumulative logics -- Semantics of nonmonotonic reasoning in logic programming -- Formulas-as-types for a hierarchy of sublogics of intuitionistic propositional logic -- Cut-elimination in logics with definitional reflection.

This volume comprises the proceedings of the First All-Berlin Workshop on Nonclassical Logics and Information Processing, held at the Free University of Berlin, November 9-10, 1990. The scope of the ten papers in the volume is broad, covering various different subfields of logic - particularly nonclassical logic - and its applications in artificial intelligence. The papers are grouped according to the four major topics that emerged at the meeting: modal systems, logic programming, nonmonotonic logics, and proof theory. The classification is only a rough guide since the four areas overlap considerably.