ed, and consequently
that of reason, when any incongruous ideas occur in the trains of
imagination, which compose our dreams; we cannot compare them with our
previous knowledge of nature and reject them; whence arises the
perpetual inconsistency of our sleeping trains of ideas; and whence in
our dreams we never feel the sentiment of novelty; however different
the ideas, which present themselves, may be from the usual course of
nature.

But in our waking hours, whenever any object occurs which does not
accord with the usual course of nature, we immediately and
unconsciously exert our voluntary power, and examine it by intuitive
analogy, comparing it with our previous knowledge of nature. This
exertion of our volition excites many other ideas, and is attended
with pleasurable sensation; which constitutes the sentiment of
novelty. But when the object of novelty stimulates us so forcibly as
suddenly to disunite our passing trains of ideas, as if a pistol be
unexpectedly discharged, the emotion of surprise is experienced; which
by exciting violent irritation and violent sensation, employs for a
time the whole sensorial energy, and thus dissevers the passing trains
of ideas; before the power of volition has time to compare them with
the usual phenomena of nature; but as the painful emotion of fear is
then generally added to that of surprise, as every one experiences,
who hears a noise in the dark, which he cannot immediately account
for; this great degree of novelty, when it produces much surprise,
generally ceases to be pleasurable, and does not then belong to
objects of taste.

In its less degree surprise is generally agreeable, as it simply
expresses the sentiment occasioned by the novelty of our ideas; as in
common language we say, we are agreeably surprised at the unexpected
meeting with a friend, which not only expresses the sentiment of
novelty, but also the pleasure from other agreeable ideas associated
with the object of it.

It must appear from hence, that different persons must be affected
more or less agreeably by different degrees or quantities of novelty
in the objects of taste; according to their previous knowledge of
nature, or their previous habits or opportunities of attending to the
fine arts. Thus before its nativity the fetus experiences the
perceptions of heat and cold, of hardness and softness, of motion and
rest, with those perhaps of hunger and repletion, sleeping and waking,
pain and pleasure; a