Results 1 
4 of
4
CutElimination and a PermutationFree Sequent Calculus for Intuitionistic Logic
, 1998
"... We describe a sequent calculus, based on work of Herbelin, of which the cutfree derivations are in 11 correspondence with the normal natural deduction proofs of intuitionistic logic. We present a simple proof of Herbelin's strong cutelimination theorem for the calculus, using the recursive path ..."
Abstract

Cited by 40 (6 self)
 Add to MetaCart
We describe a sequent calculus, based on work of Herbelin, of which the cutfree derivations are in 11 correspondence with the normal natural deduction proofs of intuitionistic logic. We present a simple proof of Herbelin's strong cutelimination theorem for the calculus, using the recursive path ordering theorem of Dershowitz.
Implicit Programming and the Logic of Constructible Duality
"... ABSTRACT We present an investigation of duality in the traditional logical manner. We extend Nelson's symmetrization of intuitionistic logic, constructible falsity, to a selfdual logic constructible duality. We develop a selfdual model by considering an interval of worlds in an intuitionistic Kr ..."
Abstract

Cited by 1 (0 self)
 Add to MetaCart
ABSTRACT We present an investigation of duality in the traditional logical manner. We extend Nelson's symmetrization of intuitionistic logic, constructible falsity, to a selfdual logic constructible duality. We develop a selfdual model by considering an interval of worlds in an intuitionistic Kripke model. The duality arises through how we judge truth and falsity. Truth is judged forward in the Kripke model, as in intuitionistic logic, while falsity is judged backwards. We develop a selfdual algebra such that every point in the algebra is representable by some formula in the logic. This algebra arises as an instantiation of a Heyting algebra into several categorical constructions. In particular, we show that this algebra is an instantiation of the Chu construction applied to a Heyting algebra, the second Dialectica construction applied to a Heyting algebra, and as an algebra for the study of recursion and corecursion. Thus the algebra provides a common base for these constructions, and suggests itself as an important part of any constructive logical treatment of duality. Implicit programming is suggested as a new paradigm for computing with constructible duality as its formal system. We show that all the operators that have computable least fixed points are definable explicitly and all operators with computable optimal fixed points are definable implicitly within constructible duality. Implicit programming adds a novel definitional mechanism that allows functions to be defined implicitly. This new programming feature is especially useful for programming with corecursively defined datatypes such as circular lists. iii DEDICATION To my cousin Jordan Lackey (19631995) whose courage with AIDS was an inspiration. iv
Computing Interpolants in Implicational Logics
"... I present a new syntactical method for proving the Interpolation Theorem for the implicational fragment of intuitionistic logic and its substructural subsystems. This method, like Prawitz’s, works on natural deductions rather than sequent derivations, and, unlike existing methods, always finds a ‘st ..."
Abstract

Cited by 1 (0 self)
 Add to MetaCart
I present a new syntactical method for proving the Interpolation Theorem for the implicational fragment of intuitionistic logic and its substructural subsystems. This method, like Prawitz’s, works on natural deductions rather than sequent derivations, and, unlike existing methods, always finds a ‘strongest ’ interpolant under a certain restricted but reasonable notion of what counts as an ‘interpolant’.
History of Mathematical Logic in Serbia
"... Abstract: The paper presents a brief historical overview of research in the area of mathematical logic and applications in Serbia. This review covers the period from the beginning of research in this area in Serbia until 1995. 1. Preface 2. Seminar on mathematical logic 3. Serbian journals in mathem ..."
Abstract
 Add to MetaCart
Abstract: The paper presents a brief historical overview of research in the area of mathematical logic and applications in Serbia. This review covers the period from the beginning of research in this area in Serbia until 1995. 1. Preface 2. Seminar on mathematical logic 3. Serbian journals in mathematical logic and applications 4. Topics of research in mathematical logic in Serbia