presupposes a feeling for it implanted in us, which is the first
condition of this satisfaction; this is just as when ignorant
persons that like to dabble in metaphysics imagine matter so subtle,
so supersubtle that they almost make themselves giddy with it, and
then think that in this way they have conceived it as a spiritual
and yet extended being. If with Epicurus we make virtue determine
the will only by means of the pleasure it promises, we cannot
afterwards blame him for holding that this pleasure is of the same
kind as those of the coarsest senses. For we have no reason whatever
to charge him with holding that the ideas by which this feeling is
excited in us belong merely to the bodily senses. As far as can be
conjectured, he sought the source of many of them in the use of the
higher cognitive faculty, but this did not prevent him, and could
not prevent him, from holding on the principle above stated, that
the pleasure itself which those intellectual ideas give us, and by
which alone they can determine the will, is just of the same kind.
Consistency is the highest obligation of a philosopher, and yet the
most rarely found. The ancient Greek schools give us more examples
of it than we find in our syncretistic age, in which a certain shallow
and dishonest system of compromise of contradictory principles is
devised, because it commends itself better to a public which is
content to know something of everything and nothing thoroughly, so
as to please every party.

The principle of private happiness, however much understanding and
reason may be used in it, cannot contain any other determining
principles for the will than those which belong to the lower
desires; and either there are no [higher] desires at all, or pure
reason must of itself alone be practical; that is, it must be able
to determine the will by the mere form of the practical rule without