A Representation Theorem for Abstract Cumulative Aggregation

From any two conditional obligations “X if A” and “Y if B”, cumulative aggregation derives the combined obligation “X ∪ Y if A ∪ (B \ X)”, whereas simple aggregation derives the obligation “X ∪ Y if A ∪ B”. We propose FC systems consisting of cumulative aggregation together with factual detachment, and we give a representation result for FC systems, as well as for FA systems consisting of simple aggregation together with factual detachment. We relate FC and FA systems to each other and to input/output logics recently introduced by Parent and van der Torre.