TRS: {f(X) -> g()} POP* + Boolean Semantic Labelling: Normal positions: pi(f_sl=1) = [1], pi(f_sl=0) = [1] Safe positions: Precedence: f_sl=0 > g_sl=0 empty Interpretation: g^(0): | 0 f^(1): 0 | 0 1 | 0 Labelling: g^(0): | 0 f^(1): 0 | 0 1 | 0 Labelled predicative System: {f_sl=0(X;) -> g_sl=0(), f_sl=0(X;) -> g_sl=0()} Qed