We propose a nonmonotonic Description Logic of typicality able to account for the phenomenon of the combination of prototypical concepts. The proposed logic relies on the logic
of typicality ALC + TR, whose semantics is based on the notion of rational closure, as well
as on the distributed semantics of probabilistic Description Logics, and is equipped with a
cognitive heuristic used by humans for concept composition.
We first extend the logic of typicality ALC + TR by typicality inclusions of the form
p :: T(C) v D, whose intuitive meaning is that “we believe with degree p about the fact that
typical Cs are Ds”. As in the distributed semantics, we define different scenarios containing
only some typicality inclusions, each one having a suitable probability. We then exploit such
scenarios in order to ascribe typical properties to a concept C obtained as the combination of
two prototypical concepts. We also show that reasoning in the proposed Description Logic is
EXPTIME-complete as for the underlying standard Description Logic ALC.