This paper argues against a thesis of Fernando Atria that considers (neo)constitutionalism to be a pre-modern law that participates in a cycle of application of law that he calls "arbitrariness to perfection". There are two objections to this thesis. The first is related to the distinction between the government of men and the government of laws which, according to Aguilo, is a distinction that tends to be exaggerated; while, for Atienza, the idea of the government of laws presupposes a formalist rationality, when it could be compatible with a more open form of rationality. The second objection is based on the fact that it also presupposes that the only ends that count in law are the ends of law itself (certainty, predictability) and not the ends of politics. I show how modern law has been transformed in such a way that it pursues and must pursue other ends (protection of human rights, redistribution, welfare, sustainable development, among others). Finally, I sustain that the judge in the constitutional or post-positivist model does not have the possibility of arbitrarily choosing to resolve by pondering or to resolve by applying rules, as suggested by the thesis of arbitrariness to perfection.