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:-s no
less evident, namely that though neither the ideas, of the memory nor
imagination, neither the lively nor faint ideas can make their appearance