NO

Problem:
 from(X) -> cons(X,from(s(X)))
 length(nil()) -> 0()
 length(cons(X,Y)) -> s(length1(Y))
 length1(X) -> length(X)

Proof:
 Containment Processor: loop length: 1
                        terms:
                         from(X)
                        context: cons(X,[])
                        substitution:
                         X -> s(X)
  Qed