[Revised entry by Edwin Mares on November 13, 2020. Changes to: Main text, Bibliography, logic-b-dj-dk.html] Relevance logics are non-classical logics. Called 'relevant logics' in Britain and Australasia, these systems developed as attempts to avoid the paradoxes of material and strict implication. These so-called paradoxes are valid conclusions that follow from the definitions of material and strict implication but are seen, by some, as problematic....