Substructural logics comprise a family of nonclassical logics that arose in response to problems in theoretical computer science, mathematical linguistics, and category theory. They include intuitionist logic, relevant logic, BCK logic, linear logic, and Lambeck's calculus of synthetic categories. This book brings together new papers by some of the most eminent authorities in these various traditions in order to provide a unified view of the field. This important volume--the first to bring together the disparate strands of work in substructural logics--will be welcomed by student and...

Proof theory and category theory were first drawn together by Lambek some 30 years ago but, until now, the most fundamental notions of category theory (as opposed to their embodiments in logic) have not been explained systematically in terms of proof theory. Here it is shown that these notions, in particular the notion of adjunction, can be formulated in such as way as to be characterised by composition elimination. Among the benefits of these composition-free formulations are syntactical and simple model-theoretical, geometrical decision procedures for the commuting of diagrams of arrows....

This book in categorial proof theory formulates in terms of category theory a generalization close to linear algebra of the notions of distributive lattice and Boolean algebra. These notions of distributive lattice category and Boolean category codify a plausible nontrivial notion of identity of proofs in classical propositional logic, which is in accordance with Gentzens cut-elimination procedure for multiple-conclusion sequents modified by admitting new principles called union of proofs and zero proofs. It is proved that these notions of category are coherent in the sense that there is a...