YES Problem: 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)) Proof: Matrix Interpretation Processor: dim=1 interpretation: [or](x0, x1) = x0 + x1 + 1, [implies](x0, x1) = 2x0 + 4x1 + 4, [not](x0) = 2x0 + 4 orientation: implies(not(x),y) = 4x + 4y + 12 >= x + y + 1 = or(x,y) implies(not(x),or(y,z)) = 4x + 4y + 4z + 16 >= 4x + 2y + 4z + 8 = implies(y,or(x,z)) implies(x,or(y,z)) = 2x + 4y + 4z + 8 >= 2x + y + 4z + 5 = or(y,implies(x,z)) problem: Qed