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524 with such signs as shew evidently he has no serious intention of binding himself, he wou'd not lie under any obligation of performance; but 'tis necessary, that the words be a perfect expression of the will, without any contrary signs. Nay, even this we must not carry so far as to imagine, that one, whom, by our quickness of understanding, we conjecture, from certain signs, to have an intention of deceiving us, is not bound by his expression or verbal promise, if we accept of it; but must limit this conclusion to those cases. where the signs are of a different kind from those of deceit. All these contradictions are easily accounted for, if the obligation of promises be merely a human invention for the convenience of society; but will never be explain'd, if it be something real and natural, arising from any action of the mind or body.

I shall farther observe, 'that since every new promise imposes a new obligation of morality on the person who promises, and since this new obligation arises from his will; 'tis one of the most mysterious and incomprehensible operations that can possibly be imagin'd, and may even be compar'd to transubstantiation, or holy orders, where a certain form of words, along with a certain intention, changes entirely the nature of an external object, and even of a human creature. But tho' these mysteries be so far alike, 'tis very remarkable, that they differ widely in other particulars, and that this difference may be regarded as a strong proof of the difference of their origins. As the obligation of promises is an invention for the interest of society, 'tis warp'd into as many different forms as that interest requires, and even runs into direct contradictions, rather than lose sight of its object. But as those other monstrous doctrines are merely priestly inventions, and have no public interest in view, they are less disturb'd in their progress by new obstacles; and it must be own'd, that, after the first absurdity,