t. These again are copied by the memory and imagination, and
become ideas; which perhaps in their turn give rise to other impressions
and ideas. So that the impressions of reflexion are only antecedent
to their correspondent ideas; but posterior to those of sensation, and
derived from them. The examination of our sensations belongs more to
anatomists and natural philosophers than to moral; and therefore shall
not at present be entered upon. And as the impressions of reflexion,
viz. passions, desires, and emotions, which principally deserve our
attention, arise mostly from ideas, it will be necessary to reverse that
method, which at first sight seems most natural; and in order to explain
the nature and principles of the human mind, give a particular account
of ideas, before we proceed to impressions. For this reason I have here
chosen to begin with ideas.

SECT. III. OF THE IDEAS OF THE MEMORY AND IMAGINATION.

We find by experience, that when any impression has been present with
the mind, it again makes its appearance there as an idea; and this it
may do after two different ways: either when in its new appearance it
retains a considerable degree of its first vivacity, and is somewhat
intermediate betwixt an impression and an idea: or when it entirely
loses that vivacity, and is a perfect idea. The faculty, by which we
repeat our impressions in the first manner, is called the MEMORY, and
the other the IMAGINATION. It is evident at first sight, that the
ideas of the memory are much more lively and strong than those of the
imagination, and that the former faculty paints its objects in more
distinct colours, than any which are employed by the latter. When we
remember any past event, the idea of it flows in upon the mind in a
forcible manner; whereas in the imagination the perception is faint and
languid, and cannot without difficulty be preserved by the mind
steddy and uniform for any considerable time. Here then is a sensible
difference betwixt one species of ideas and another. But of this more
fully hereafter.[Part II, Sect. 5.]

There is another difference betwixt these two kinds of ideas, which is
no less evident, namely that though neither the ideas, of the memory
nor imagination, neither the lively nor faint ideas can make their
appearance in the mind, unless their correspondent impressions have
gone before to prepare the way for them, yet the imagination is not
restrained to the same order and form with the