YES We show the termination of the TRS R: implies(not(x),y) -> or(x,y) implies(not(x),or(y,z)) -> implies(y,or(x,z)) implies(x,or(y,z)) -> or(y,implies(x,z)) -- SCC decomposition. Consider the dependency pair problem (P, R), where P consists of p1: implies#(not(x),or(y,z)) -> implies#(y,or(x,z)) p2: implies#(x,or(y,z)) -> implies#(x,z) and R consists of: r1: implies(not(x),y) -> or(x,y) r2: implies(not(x),or(y,z)) -> implies(y,or(x,z)) r3: implies(x,or(y,z)) -> or(y,implies(x,z)) The estimated dependency graph contains the following SCCs: {p1, p2} -- Reduction pair. Consider the dependency pair problem (P, R), where P consists of p1: implies#(not(x),or(y,z)) -> implies#(y,or(x,z)) p2: implies#(x,or(y,z)) -> implies#(x,z) and R consists of: r1: implies(not(x),y) -> or(x,y) r2: implies(not(x),or(y,z)) -> implies(y,or(x,z)) r3: implies(x,or(y,z)) -> or(y,implies(x,z)) The set of usable rules consists of (no rules) Take the reduction pair: matrix interpretations: carrier: N^1 order: standard order interpretations: implies#_A(x1,x2) = x2 not_A(x1) = x1 + 1 or_A(x1,x2) = x2 + 1 The next rules are strictly ordered: p2 We remove them from the problem. -- SCC decomposition. Consider the dependency pair problem (P, R), where P consists of p1: implies#(not(x),or(y,z)) -> implies#(y,or(x,z)) and R consists of: r1: implies(not(x),y) -> or(x,y) r2: implies(not(x),or(y,z)) -> implies(y,or(x,z)) r3: implies(x,or(y,z)) -> or(y,implies(x,z)) The estimated dependency graph contains the following SCCs: {p1} -- Reduction pair. Consider the dependency pair problem (P, R), where P consists of p1: implies#(not(x),or(y,z)) -> implies#(y,or(x,z)) and R consists of: r1: implies(not(x),y) -> or(x,y) r2: implies(not(x),or(y,z)) -> implies(y,or(x,z)) r3: implies(x,or(y,z)) -> or(y,implies(x,z)) The set of usable rules consists of (no rules) Take the reduction pair: matrix interpretations: carrier: N^1 order: standard order interpretations: implies#_A(x1,x2) = x1 + x2 not_A(x1) = x1 + 1 or_A(x1,x2) = x1 The next rules are strictly ordered: p1 We remove them from the problem. Then no dependency pair remains.