Abstract
In the present paper we propose a system of propositional logic for reasoning about
justification, truthmaking, and the connection between justifiers and truthmakers. The logic of
justification and truthmaking is developed according to the fundamental ideas introduced by
Artemov. Justifiers and truthmakers are treated in a similar way, exploiting the intuition that
justifiers provide epistemic grounds for propositions to be considered true, while truthmakers
provide ontological grounds for propositions to be true. This system of logic is then applied
both for interpreting the notorious definition of knowledge as justified true belief and for advancing a new solution to Gettier counterexamples to this standard definition.