  Justification theory is a unifying framework for semantics of non-monotonic
logics. It is built on the notion of a justification, which intuitively is a
graph that explains the truth value of certain facts in a structure. Knowledge
representation languages covered by justification theory include logic
programs, argumentation frameworks, inductive definitions, and nested inductive
and coinductive definitions. In addition, justifications are also used for
implementation purposes. They are used to compute unfounded sets in modern ASP
solvers, can be used to check for relevance of atoms in complete search
algorithms, and recent lazy grounding algorithms are built on top of them. In
this extended abstract, we lay out possible extensions to justification theory.
