Abstract

In recent years the study of topic or subject matter has found application in the analysis of epistemic attitudes such as knowledge and belief. To know or believe $$\varphi,$$ one needs to grasp $$\varphi$$’s topic, i.e. what $$\varphi$$ is about. This yields a hyperintensional treatment of epistemic attitudes: if two necessary equivalent sentences differ in subject matter, they cannot be substituted _salva veritate_ in the context of those attitudes. In this paper, I aim to extend this approach to propositional justification. I argue that, in contrast to epistemic attitudes, having propositional justification for $$\varphi$$ does not require grasping the totality of $$\varphi$$’s topic, but only part of it. This is the case because one may possess evidence for $$\varphi$$ even without grasping the totality of $$\varphi$$’s topic. I define what it means to be evidence for a proposition, borrowing some notions from the logical grounding literature. Building on extant frameworks modelling evidential support and subject matter, I then put forward a modal clause for propositional justification. Finally, I prove—together with the failure of some undesired principles—a ground-theoretic closure principle for the justification operator and show how it entails closure under Strong Kleene logic.