BOOK III PART II
duce any obligation. This appears evidently
from the foregoing reasoning. A promise cre-
ates a new obligation. A new obligation sup-
poses new sentiments to arise. The will never
creates new sentiments. There could not nat-
urally, 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 ev-
idently 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 ac-
tion. This motive cannot be the sense of duty.
A sense of duty supposes an antecedent obli-
gation: And where an action is not required by
any natural passion, it cannot be required by