We consider the system counterex1. Alphabet: f : [nat * nat] --> nat g : [nat -> nat] --> nat Rules: f(g(/\x.f(x, x)), g(/\y.f(y, y))) => (/\z.f(z, z)) g(/\u.f(u, u)) This AFS is converted to an AFSM simply by replacing all free variables by meta-variables (with arity 0). It is easy to see that this system is non-terminating: f(g(/\x.f(x, x)), g(/\y.f(y, y))) => (/\x.f(x, x)) g(/\y.f(y, y)) => f(g(/\x.f(x, x)), g(/\y.f(y, y))) That is, a term s reduces to a term t which instantiates s.