The asserted inputs of a precept can be viewed as
critical features characterizing a class of examples
(namely those represented by the precept). Hence,
precepts are a form of intension. Since PDL2 supports
prior knowledge in the form of precepts, it can
beneficially use the intensional approach. In this case,
the system is given (a priori) the defaults and their
relative priorities (based on some external source, e.g.,
religion is more important than politics). During an
execution where several conflicting defaults apply
equally well, all of the defaults have the same
activation. If they also have the same generality (as in
Example 1), PDL2 automatically causes the default
with highest priority to win the competition. If they
differ in generality, PDL2 chooses the more specific as
the winner. Such an a priori ordering of defaults may
not always be available, nor realistic however.