Hart is a legal positivist, but he is a critical moral philosopher as well. Legal positivism generally means that it is in no sense a necessary truth that laws reproduce or satisfy certain demands of morality, though in fact they have often done S0. It is worth noting that Hart does not subscribe to all the theses commonly attributed to legal positivism. He does not assert that laws are simply a product of sovereign command, or that moral judgments cannot be established as statements of facts can, by rational argument, evidence or proof. He does not maintain that a legal system is a closed logical system in which correct decisions can be deduced from predetermined legal rules by logical means alone.