are two correlative ideas, because change
presupposes permanence, and a limited reality implies an infinite
reality. If the formal impulsion becomes receptive, that is, if thought
anticipates sensation, and the person substitutes itself in the place of
the world, it loses as a subject and autonomous force what it gains as
object, because immutability implies change, and that to manifest itself
also absolute reality requires limits. As soon as man is only form, he
has no form, and the personality vanishes with the condition. In a word,
it is only inasmuch as he is spontaneous, autonomous, that there is
reality out of him, that he is also receptive; and it is only inasmuch as
he is receptive that there is reality in him, that he is a thinking
force.

Consequently these two impulsions require limits, and looked upon as
forces, they need tempering; the former that it may not encroach on the
field of legislation, the latter that it may not invade the ground of
feeling. But this tempering and moderating the sensuous impulsion ought
not to be the effect of physical impotence or of a blunting of
sensations, which is always a matter for contempt. It must be a free
act, an activity of the person, which by its moral intensity moderates
the sensuous intensity, and by the sway of impressions takes from them in
depth what it gives them in surface or breadth. The character must place
limits to temperament, for the senses have only the right to lose
elements if it be to the advantage of the mind. In its turn, the
tempering of the formal impulsion must not result from moral impotence,
from a relaxation of thought and will, which would degrade humanity. It
is necessary that the glorious source of this second tempering should be
the fulness of sensations; it is necessary that sensuousness itself
should defend its field with a victorious arm and resist the violence
that the invading activity of the mind would do to it. In a word, it is
necessary that the material impulsion should be contained in the limits
of propriety by personality, and the formal impulsion by receptivity or
nature.

LETTER XIV.

We have been brought to the idea of such a correlation between the two
impulsions that the action of the one establishes and limits at the same
time the action of the other, and that each of them, taken in isolation,
does arrive at its highest manifestation just because the other is
active.

No doubt this correlation of the two imp