YES # parallel critical pair closing system (Shintani and Hirokawa 2022) Consider the left-linear TRS R: from(x) -> :(x,from(s(x))) sel(0(),:(y,z)) -> y sel(s(x),:(y,z)) -> sel(x,z) Let C be the following subset of R: (empty) The TRS R is left-linear and all parallel critical pairs are joinable by C. Therefore, the confluence of R follows from that of C. # emptiness The empty TRS is confluent.