We may of ourselves acknowledge, that such an object is valuable, and such another odious; but until an orator excites the imagination, and gives force to these ideas, they may have but a feeble influence either on the will or the affections.
But eloquence is not always necessary.

The bare opinion of another, especially when inforced with passion, will cause an idea of good or evil to have an influence upon us, which would otherwise have been entirely neglected.

This proceeds from the principle of sympathy or communication; and sympathy, as I have already observed, is nothing but the conversion of an idea into an impression by the force of imagination.
It is remarkable, that lively passions commonly attend a lively imagination.

In this respect, as well as others, the force of the passion depends as much on the temper of the person, as the nature or situation of the object.
I have already observed, that belief is nothing but a lively idea related to a present impression.

This vivacity is a requisite circumstance to the exciting all our passions, the calm as well as the violent; nor has a mere fiction of the imagination any considerable influence upon either of them.