these two faculties of the animal sensorium. Pride, hope, joy, are the
names of particular pleasures: shame, despair, sorrow, are the names of
peculiar pains: and love, ambition, avarice, of particular desires: hatred,
disgust, fear, anxiety, of particular aversions. Whilst the passion of
anger includes the pain from a recent injury, and the aversion to the
adversary that occasioned it. And compassion is the pain we experience at
the sight of misery, and the desire of relieving it.

There is another tribe of desires, which are commonly termed appetites, and
are the immediate consequences of the absence of some irritative motions.
Those, which arise from defect of internal irritations, have proper names
conferred upon them, as hunger, thirst, lust, and the desire of air, when
our respiration is impaired by noxious vapours; and of warmth, when we are
exposed to too great a degree of cold. But those, whose stimuli are
external to the body, are named from the objects, which are by nature
constituted to excite them; these desires originate from our past
experience of the pleasurable sensations they occasion, as the smell of an
hyacinth, or the taste of a pine-apple.

Whence it appears, that our pleasures and pains are at least as various and
as numerous as our irritations; and that our desires and aversions must be
as numerous as our pleasures and pains. And that as sensation is here used
as a general term for our numerous pleasures and pains, when they produce
the contractions of our fibres; so volition is the general name for our
desires and aversions, when they produce fibrous contractions. Thus when a
motion of the central parts, or of the whole sensorium, terminates in the
exertion of our muscles, it is generally called voluntary action; when it
terminates in the exertion of our ideas, it is termed recollection,
reasoning, determining.