effect. But this very argument may, perhaps, be turned against me, and
instead of a confirmation of my hypothesis, may become an objection to
it. For it may be said, that if all the parts of that hypothesis be true,
viz. that these three species of relation are derived from the same
principles; that their effects in informing and enlivening our ideas are
the same; and that belief is nothing but a more forcible and vivid
conception of an idea; it should follow, that that action of the mind may
not only be derived from the relation of cause and effect, but also from
those of contiguity and resemblance. But as we find by experience, that
belief arises only from causation, and that we can draw no inference
from one object to another, except they be connected by this relation, we
may conclude, that there is some error in that reasoning, which leads us
into such difficulties.

This is the objection; let us now consider its solution. It is evident,
that whatever is present to the memory, striking upon the mind with a
vivacity, which resembles an immediate impression, must become of
considerable moment in all the operations of the mind, and must easily
distinguish itself above the mere fictions of the imagination. Of these
impressions or ideas of the memory we form a kind of system,
comprehending whatever we remember to have been present, either to our
internal perception or senses; and every particular of that system,
joined to the present impressions, we are pleased to call a reality. But
the mind stops not here. For finding, that with this system of
perceptions, there is another connected by custom, or if you will, by the
relation of cause or effect, it proceeds to the consideration of their
ideas; and as it feels that it is in a manner necessarily determined to
view these particular ideas, and that the custom or relation, by which it
is determined, admits not of the least change, it forms them into a new
system, which it likewise dignifies with the title of realities. The