ent, and that
the obligation arises from our mere will and pleasure. The only question
then is, whether there be not a manifest absurdity in supposing this
act of the mind, and such an absurdity as no man coued fall into,
whose ideas are not confounded with prejudice and the fallacious use of
language.

All morality depends upon our sentiments; and when any action, or
quality of the mind, pleases us after a certain manner, we say it is
virtuous; and when the neglect, or nonperformance of it, displeases us
after a like manner, we say that we lie under an obligation to perform
it. A change of the obligation supposes a change of the sentiment; and
a creation of a new obligation supposes some new sentiment to arise. But
it is certain we can naturally no more change our own sentiments, than
the motions of the heavens; nor by a single act of our will, that is,
by a promise, render any action agreeable or disagreeable, moral
or immoral; which, without that act, would have produced contrary
impressions, or have been endowed with different qualities. It would
be absurd, therefore, to will any new obligation, that is, any new
sentiment of pain or pleasure; nor is it possible, that men coued
naturally fall into so gross an absurdity. A promise, therefore, is
naturally something altogether unintelligible, nor is there any act of
the mind belonging to it.

[Footnote 21 Were morality discoverable by reason, and not
by sentiment, it would be still more evident, that promises
cou'd make no alteration upon it. Morality is suppos'd to
consist in relation. Every new imposition of morality,
therefore, must arise from some new relation of objects; and
consequently the will coud not produce immediately any
change in morals, but cou'd 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.

Shou'd it be said, that this act of the will being in effect
a new object, produces new relations and new duties; I wou'd
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 form'd by
the volition itself,