Adjoint interpretations of sentential calculi (Q2266005)

This large step towards a general theory of mutual interpretability of sentential calculi by treating the class of all sentential calculi as a quasiordered class is self-contained but demanding. It is useful to understand the elements of category theory and be familiar with how Polish logicians investigate consequence operations in sentential calculi. Sentential calculi are treated as preorders under consequence operations. Interpretations are certain order preserving functions (functors) on sentential calculi into another. The key notion investigated is that of a special inverse of an interpretation: The Left Adjoint of an Interpretation. In several definitions and theorems the author shows how powerful left adjuncts are for comparing sentential calculi.