Enquiry Concerning Human Understanding

Moral philosophy, or the science of human nature, may be treated
after two different manners; each of which has its peculiar merit, and
may contribute to the entertainment, instruction, and reformation of
mankind. The one considers man chiefly as born for action; and as
influenced in his measures by taste and sentiment; pursuing one object,
and avoiding another, according to the value which these objects seem to
possess, and according to the light in which they present themselves. As
virtue, of all objects, is allowed to be the most valuable, this species
of philosophers paint her in the most amiable colours; borrowing all
helps from poetry and eloquence, and treating their subject in an easy
and obvious manner, and such as is best fitted to please the
imagination, and engage the affections. They select the most striking
observations and instances from common life; place opposite characters
in a proper contrast; and alluring us into the paths of virtue by the
views of glory and happiness, direct our steps in these paths by the
soundest precepts and most illustrious examples. They make us _feel_ the
difference between vice and virtue; they excite and regulate our
sentiments; and so they can but bend our hearts to the love of probity
and true honour, they think, that they have fully attained the end of
all their labours.