We may draw the same conclusion, concerning the origin of promises, from the force which is supposed to invalidate all contracts, and to free us from their obligation. Such a principle is a proof that promises have no natural obligation, and are mere artificial contrivances for the convenience and advantage of society. If we consider aright of the matter, force is not essentially different from any other motive of hope or fear, which may induce us to engage our word, and lay ourselves under any obligation. A man, dangerously wounded, who promises a competent sum to a surgeon to cure him, would certainly be bound to performance; though the case be not so much different from that of one who promises a sum to a robber, as to produce so great a difference in our sentiments of morality, if these sentiments were not built entirely on public interest and convenience. [7] Were morality discoverable by reason, and not by sentiment, 'twould be still more evident that promises could make no alteration upon it. Morality is supposed to consist in relation. Every new imposition of morality, therefore, must arise from some new relation of objects; and consequently the will could not produce immediately any change in morals, but could have that effect only by producing a change upon the objects. But as the moral obligation of a promise is the pure effect of the will, without the least change in any part of the universe, it follows, that promises have no natural obligation. Should it be said, that this act of the will, being in effect a new object, produces new relations and new duties; I would answer, that this is a pure sophism, which may be detected by a very moderate share of accuracy and exactness. To will a new obligation, is to will a new relation of objects; and therefore, if this new relation of objects were formed by the volition itself, we should, in effect, will the volition, which is plainly absurd and impossible. The will has here no object to which it could tend, but must return upon itself in _infinitum_. The new obligation depends upon new relations. The new relations depend upon a new volition. The new volition has for object a new obligation, and consequently new relations, and consequently a new volition; which volition, again, has in view a new obligation, relation and volition, without any termination. 'Tis impossible, therefore, we could ever will a new obligation; and consequently 'tis impossible the will could ever accompany a promise, or produce a new obligation of morality. [8] I mean so far as holy orders are supposed to produce the _indelible Character_. In other respects they are only a legal qualification. SECTION VI. SOME FARTHER REFLECTIONS CONCERNING JUSTICE AND INJUSTICE.