YES # Compositional critical pair system (Shintani and Hirokawa 2022). Consider the left-linear TRS R: +(0(),y) -> y +(s(0()),y) -> s(y) s(s(x)) -> x Let C be the following subset of R: (empty) The critical pair system CPS(R,C) is: s(s(s(x0))) -> s(x0) The TRS R is locally confluent and CPS(R,C)/R is terminating. Therefore, the confluence of R follows from that of C. # Emptiness. The empty TRS is confluent.