In fact, if the sensuous impulsion becomes determining, if the senses become lawgivers, and if the world stifles personality, he loses as object what he gains in force. It may be said of man that when he is only the contents of time, he is not and consequently _he has_ no other contents. His condition is destroyed at the same time as his personality, because these 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.