we should in effect will the volition;
which is plainly absurd and impossible. The will has here no
object to which it cou'd 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. It is impossible,
therefore, we cou'd ever will a new obligation; and
consequently it is impossible the will cou'd ever accompany
a promise, or produce a new obligation of morality.]

But, secondly, if there was any act of the mind belonging to it, it
could not naturally produce any obligation. This appears evidently
from the foregoing reasoning. A promise creates a new obligation. A new
obligation supposes new sentiments to arise. The will never creates new
sentiments. There could not naturally, therefore, arise any obligation
from a promise, even supposing the mind could fall into the absurdity of
willing that obligation.

The same truth may be proved still more evidently by that reasoning,
which proved justice in general to be an artificial virtue. No action
can be required of us as our duty, unless there be implanted in human
nature some actuating passion or motive, capable of producing the
action. This motive cannot be the sense of duty. A sense of duty
supposes an antecedent obligation: And where an action is not required
by any natural passion, it cannot be required by any natural obligation;
since it may be omitted without proving any defect or imperfection
in the mind and temper, and consequently without any vice. Now it is
evident we have no motive leading us to the performance of promises,
distinct from a sense of duty. If we thought, that promises had no moral
obligation, we never should feel any inclination to observe them. This
is not the case with the natural virtues. Though there was no obligation
to relieve the miserable, our humanity would lead us to it; and when we
omit that duty, the immorality of the omission arises from its being a
proof, that we want the natural sentiments of humanity. A father knows
it to be his duty to take care of his children: But he has also a
natural inclination to it. And if no human creature had that indination,
no one coued lie under any such o