YES Problem: strict: f(f(x)) -> x weak: f(x) -> g(f(g(f(x)))) Proof: Arctic Interpretation Processor: dimension: 3 interpretation: [0 -& 0 ] [g](x0) = [0 -& 0 ]x0 [0 -& 0 ] , [0 0 0] [f](x0) = [2 1 3]x0 [0 0 0] orientation: [2 1 3] f(f(x)) = [3 3 4]x >= x = x [2 1 3] [0 0 0] [0 0 0] f(x) = [2 1 3]x >= [0 0 0]x = g(f(g(f(x)))) [0 0 0] [0 0 0] problem: strict: weak: f(x) -> g(f(g(f(x)))) Qed