The Ontology of Justifications in the Logical Setting

Justification Logic provides an axiomatic description of justifications and delegates the question of their nature to semantics. In this note, we address the conceptual issue of the logical type of justifications: we argue that justifications in the logical setting are naturally interpreted as sets of formulas which leads to a class of epistemic models that we call modular models. We show that Fitting models for Justification Logic naturally encode modular models and can be regarded as convenient pre-models of the former.