Constructivism and Relevance

Abstract While constructivism and relevance characterize distinct movements in nonclassical logic, they are intimately related in ways that have not been fully appreciated. In this paper, we draw out some of these connections by focusing on certain heterodox strong relevant logics that embody both constructivist and relevant features. The relations between these logics and systems such as intuitionistic logic are examined from several perspectives, including semantically using operational models and proof-theoretically using natural deduction. Along the way, we illustrate how our approach yields novel insights into intuitionistic logic, and we highlight directions for future research.