The class of definite aggregate programs is an extension of the class of definite logic programs and has a monotone immediate consequence operator.
If the function was - monotone, then the steady state would be unique.
The idea here is to block propagation by constructing a monotone upper solution to the steady state problem.
Models of unified algebra specifications are join semi-lattices, equipped with a distinguished subset of individuals, together with monotone functions.
Monotone functions between partial orders are non-expansive functions with respect to their corresponding quasi-metrics.
In this logic two operators and are present, which express the least and greatest fixpoints of monotone operators on sets.
In section 4 we give an interpretation of the types of our systems as monotone operators on value sets.
For monotone and anti-monotone aggregates the truth value can be computed directly on the boundary multisets.
