Optimal fixedpoints of logic programs

AbstractFrom a declarative programming point of view, Manna and Shamir's optimal fixedpoint semantics is more appealing than the least fixedpoint semantics. However in standard formalisms of recursive programming the optimal fixedpoint is not computable while the least fixedpoint is. In the context of logic programming we show that the optimal fixedpoint is equal to the least fixedpoint and is computable. Furthermore the optimal fixedpoint semantics is consistent with Van Emden and Kowalski's semantics of logic programs