9. No one would seriously maintain that the system of rights and obligations, as it is anywhere enforced by law,--the 'jus' or 'Recht' of any nation--is all that it ought to be. Even Hobbes holds that a law, though it cannot be unjust, may be pernicious. But there has been much objection to the admission of _natural_ rights and obligations. At any rate the phrase is liable to misinterpretation. It may be taken to imply that rights and obligations can exist in a 'state of nature'--a state in which every individual is free to do as he likes--; that legal rights and obligations derive their authority from a voluntary act by which individuals contracted themselves out of this state; and that the individual retains from the state of nature certain rights with which no legal obligations ought to conflict. Such a doctrine is generally admitted to be untenable; but it does not follow from this that there is not a true and important sense in which natural rights and obligations exist,--the same sense as that in which duties may be said to exist though unfulfilled. There is a system of rights and obligations which _should be_ maintained by law, whether it is so or not, and which may properly be called 'natural'; not in the sense in which the term 'natural' would imply that such a system ever did exist or could exist independently of force exercised by society over individuals, but 'natural' because necessary to the end which it is the vocation of human society to realise. 10. The 'jus naturae,' thus understood, is at once distinguished from the sphere of moral duty, and relative to it. It is distinguished from it because admitting of enforcement by law. Moral duties do not admit of being so enforced. The question sometimes put, whether moral duties should be enforced by law, is really an unmeaning one; for they simply cannot be enforced. They are duties to act, it is true, and an act can be enforced: but they are duties to act from certain dispositions and with certain motives, and these cannot be enforced. Nay, the enforcement of an outward act, the moral character of which depends on a certain motive and disposition, may often contribute to render that motive and disposition impossible: and from this fact arises a limitation to the proper province of law in enforcing acts, which will have to be further considered below. When obligations then are spoken of in this connection, as part of the 'jus naturae' correlative to rights, they must always be understood not as moral duties, not as relative to states of will, but as relative to outward acts, of which the performance or omission can and should be enforced. There is a moral duty to discharge such obligations, and to do so in a certain spirit, but the obligation is such as that with which law has to do or may have to do, is relative to an outward act merely, and does not amount to a moral duty. There is a moral duty in regard to obligations, but there can be no obligation in regard to moral duties.