NO Problem 1: (VAR v_NonEmpty:S X:S) (RULES c -> f(g(c)) f(g(X:S)) -> g(X:S) ) Problem 1: Dependency Pairs Processor: -> Pairs: C -> C C -> F(g(c)) -> Rules: c -> f(g(c)) f(g(X:S)) -> g(X:S) Problem 1: Infinite Processor: -> Pairs: C -> C C -> F(g(c)) -> Rules: c -> f(g(c)) f(g(X:S)) -> g(X:S) -> Pairs in cycle: C -> C The problem is infinite.