Writers on jurisprudence often stress that conflict between positive laws and morality does not invalidate the positive laws. A law which requires me to compensate another for an injury caused by a dangerous object kept on my property is not invalidated by the fact that I have not been negligent and have no moral obligation to compensate the injured person. And although I have a moral obligation to keep my promises, positive laws may validly imply that I need not keep promises not made for a consideration or under seal. Thus positive law may permit acts not permitted by morals and may forbid acts permitted by morals. The lesson drawn from these thoughts is that to establish a positive law as valid we need not consider the relationships it bears to the rules of morals. A valid law is simply a law created in accordance with the constitutional conventions or ‘rules of recognition’ of the society in which it is to be applied. It is the manner of its establishment, not its relationship to morals, which makes a law valid.