BOOK I PART III
assents, not only conceives the ideas accord-
ing to the proposition, but is necessarily deter-
mined to conceive them in that particular man-
ner, either immediately or by the interposition
of other ideas. Whatever is absurd is unintel-
ligible; nor is it possible for the imagination
to conceive any thing contrary to a demonstra-
tion. But as in reasonings from causation, and
concerning matters of fact, this absolute neces-
sity cannot take place, and the imagination is
free to conceive both sides of the question, I still
ask, Wherein consists the deference betwixt in-
credulity and belief? since in both cases the
conception of the idea is equally possible and
requisite.
It will not be a satisfactory answer to say, that
a person, who does not assent to a proposition
you advance; after having conceived the ob-