Abstract
We introduce a way of reasoning about preferences represented as pairwise comparative statements, based on a very simple yet appealing principle: cancelling out common values across statements. We formalize and streamline this procedure
with argument schemes. As a result, any conclusion drawn by means of this approach comes along
with a justification. It turns out that the statements
which can be inferred through this process form a
proper preference relation. More precisely, it corresponds to a necessary preference relation under the
assumption of additive utilities. We show the inference task can be performed in polynomial time in
this setting, but that finding a minimal length explanation is NP-complete