
322 Foundations of Semantic Web Technologies
Explicitly consider all siblings, i.e. classes having a common su-
perclass, whether it is possible that an individual is an instance of
both classes. If not, declare them as disjoint.
8.3.2.2 Don’t forget role characteristics
Just like class disjointness, characteristics that can be assigned to roles (or
properties, respectively) can enable a lot of useful deductions.
Consider for every role occurring in an ontology whether it rep-
resents a transitive, symmetric, functional, and/or inverse func-
tional rel ation.
Note that in OWL 2, even more information about roles c an (and should)
be expressed: reflexivit ...