We may ascertain the nature and quality of pleasure more clearly if we start again from
Now the act of sight appears to be perfect at any moment of its duration; it does not
require anything to supervene later in order to perfect its specific quality. But pleasure
also appears to be a thing of this nature. For it is a whole, and one cannot at any moment
put one's hand on a pleasure which will only exhibit its specific quality perfectly if its
duration be prolonged.
It follows also that pleasure is not a form of motion.1
For every motion or process of change
involves duration, and is a means to an end, for
instance the process of building a house; and it is perfect when it has effected its end.
Hence a motion is perfect either when viewed over the whole time of its duration, or at
the moment when its end has been achieved. The several motions occupying portions of the
time of the whole are imperfect, and different in kind from the whole and from each other.
For instance, in building a temple the fitting together of the stones is a different
process from the fluting of a column, and both are different from the construction of the
temple as a whole; and whereas the building of the temple is a perfect process, for
nothing more is required to achieve the end proposed, laying the foundation and
constructing the triglyphs are imperfect processes, since each produces only a part of the
design; they are therefore specifically different from the construction of the whole, and
it is not possible to lay one's finger on a motion specifically perfect at any moment of
the process of building, but only, if at all, in the whole of its duration.
And the same is true of walking and the other forms of locomotion. For if locomotion is
motion from one point in space to another, and if this is of different kinds, flying,
walking, leaping and the like, and not only so, but if there are also differences in
walking itself （for the terminal points of a race course are not the same as
those of a portion of the course, nor are those of one portion the same as those of
another; nor is traversing this line the same as traversing that one,2
runner does not merely travel along a certain line but travels along a line that is in a
certain place, and this line is in a different place from
that）—however, for a full treatment of the subject of motion I must
refer to another work,3
but it appears that a motion is not perfect at every moment, but the many
movements which make up the whole are imperfect; and different from each other in kind,
inasmuch as the terminal points of a movement constitute a specific quality.
The specific quality of pleasure on the contrary is perfect at any
moment. It is clear therefore that pleasure is not the same as motion, and that it is a
whole and something perfect.
This may also be inferred from the fact that a movement necessarily occupies a space of
time, whereas a feeling of pleasure does not, for every moment of pleasurable
consciousness is a perfect whole.
These considerations also show that it is a mistake to speak of pleasure as the result of
a motion or of a process of generation. For we cannot so describe everything, but only
such things as are divided into parts and are not wholes. Thus an act of sight, a
geometrical point, an arithmetical unit are not the result of a process of generation
（nor is any of them a motion or process4
）. Pleasure therefore also is
not the result of a motion or process; for pleasure is a whole.
Again, inasmuch as each of the senses acts in relation to its object, and acts perfectly
when it is in good condition and directed to the finest of the and objects that belong to
it （for this seems to be the best description of perfect activity, it being
assumed to make no difference whether it be the sense itself that acts or the organ in
which the sense resides）, it follows that the activity of any of the senses is at
its best when the sense-organ being in the best condition is directed to the best of its
objects; and this activity will be the most perfect
and the pleasantest. For each sense has a corresponding pleasure, as also have thought and
speculation, and its activity is pleasantest when it is most perfect, and most perfect
when the organ is in good condition and when it is directed to the most excellent of its
objects; and the pleasure perfects the activity.
pleasure does not however perfect the activity in the same way as the object perceived and
the sensory faculty, if good, perfect it; just as health and the physician are not in the
same way the cause of being healthy.
（It is clear that each of the senses is accompanied by pleasure, since we apply
the term pleasant to sights and sounds5
; and it is also
clear that the pleasure is greatest when the sensory faculty is both in the best condition
and acting in relation to the best object; and given excellence in the perceived object
and the percipient organ, there will always be pleasure when an object to cause it and a
subject to feel it are both present.）
But the pleasure perfects the activity, not as the fixed disposition does, by being
already present in the agent, but as a supervening perfection, like the bloom of health in
the young and vigorous.
So long therefore as both object thought of or perceived, and subject discerning or
judging, are such as they should be, there will be pleasure in the activity; since while both the
passive and the active parties to a relationship remain the same in themselves and
unaltered in their relation to one another, the same result is naturally produced.
How is it then that no one can feel pleasure continuously? Perhaps it is due to fatigue,
since no human faculty is capable of uninterrupted activity, and therefore pleasure also
is not continuous, because it accompanies the activity of the faculties. It is for the
same reason that some things please us when new, but cease to give so much pleasure later;
this is because at first the mind is stimulated, and acts vigorously in regard to the
object, as in the case of sight when we look at something intently; but afterwards the
activity is less vigorous and our attention relaxes, and consequently the pleasure also
It might be held that all men seek to obtain pleasure, because all men desire life. Life
is a form of activity, and each man exercises his activity upon those objects and with
those faculties which he likes the most: for example, the musician exercises his sense of
hearing upon musical tunes, the student his intellect upon problems of philosophy, and so
on. And the pleasure of these activities perfects the activities, and therefore perfects
life, which all men seek.
Men have good reason therefore
to pursue pleasure, since it perfects for each his life, which is a desirable thing. The
question whether we desire life for the sake of pleasure or pleasure for the sake of life,
need not be raised for the present. In any case they appear to be inseparably united; for there is no pleasure without activity, and
also no perfect activity without its pleasure.