YES Problem: f(x) -> g(x) f(x) -> h(f(x)) h(f(x)) -> h(g(x)) g(x) -> h(g(x)) Proof: Church Rosser Transformation Processor: strict: f(x) -> g(x) f(x) -> h(f(x)) h(f(x)) -> h(g(x)) g(x) -> h(g(x)) weak: critical peaks: 4 g(x) <-0|[]- f(x) -1|[]-> h(f(x)) h(g(x)) <-0|0[]- h(f(x)) -2|[]-> h(g(x)) h(f(x)) <-1|[]- f(x) -0|[]-> g(x) h(h(f(x))) <-1|0[]- h(f(x)) -2|[]-> h(g(x)) Closedness Processor (*strongly -- <=7 steps*): strict: weak: Qed