[DL] Question on DL negation

[Maurizio Lenzerini]

I am not sure I understand your question. However, rules with one 
negated atom in the head are typically disjointness constraints 
(asserting that a set of predicates do not have common instances), and 
usually introducing these constraints in a DL is not complex.

Matt Williams ha scritto:
> Dear All,
> 
> As I understand, most DL's do not allow for the negation of roles.
> 
> However, given a formula of the form R(x,y) (where R is some role), 
> since this is equivalent to (R(x,y) & \top(y)) which could be negated as 
> ¬( R(x,y) & \top(y)), is it possible to effectively relax this 
> constraint in some cases without affecting the logic?
> 
> I'm interested in rules that have a single role as the head, and 
> negation of such heads would be useful...
> 
> Thanks,
> 
> Matt

-- 
Maurizio

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Prof. Maurizio Lenzerini
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Università degli Studi di Roma "La Sapienza"
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