This mixture of truth and falshood in the fables of tragic poets not
only serves our present purpose, by shewing, that the imagination can be
satisfyed without any absolute belief or assurance; but may in another
view be regarded as a very strong confirmation of this system. It is
evident, that poets make use of this artifice of borrowing the names
of their persons, and the chief events of their poems, from history, in
order to procure a more easy reception for the whole, and cause it
to make a deeper impression on the fancy and affections. The several
incidents of the piece acquire a kind of relation by being united into
one poem or representation; and if any of these incidents be an object
of belief, it bestows a force and vivacity on the others, which are
related to it. The vividness of the first conception diffuses itself
along the relations, and is conveyed, as by so many pipes or canals,
to every idea that has any communication with the primary one. This,
indeed, can never amount to a perfect assurance; and that because
the union among the ideas is, in a manner, accidental: But still it
approaches so near, in its influence, as may convince us, that they
are derived from the same origin. Belief must please the imagination
by means of the force and vivacity which attends it; since every idea,
which has force and vivacity, is found to be agreeable to that faculty.
To confirm this we may observe, that the assistance is mutual betwixt
the judgment and fancy, as well as betwixt the judgment and passion;
and that belief not only gives vigour to the imagination, but that a
vigorous and strong imagination is of all talents the most proper to
procure belief and authority. It is difficult for us to withhold our
assent from what is painted out to us in all the colours of eloquence;
and the vivacity produced by the fancy is in many cases greater than
that which arises from custom and experience. We are hurried away by the
lively imagination of our author or companion; and even he himself is
often a victim to his own fire and genius.