"'I am dying because I did not believe you'" ("'Je meurs pour ne vous avoir pas crue'"), the Présidente de Tourvel cries out to Madame Volanges in Letter One Hundred and Forty-seven. The importance of faith as an aspect of moral conduct is emphasized in this section. The Présidente de Tourvel is ruined by her inability to believe the advice provided by other women. Her pleasure in love ruins her faith and interest in other women's experiences. The Vicomte de Valmont's pride, and his inability to take a joke, essentially, an inability to have faith in himself, renders him incapable of continuing his affair with Tourvel.
Faith is equated with selflessness here, though this kind of faith does not always rest on the same side of the moral dilemma as religion. It is a kind of trueness to oneself, a confidence not easily attained by those who prefer to live their lives in intrigues and literary games.
This confusion of faith with sense of self leads us to the heart of the Présidente de Tourvel's sickness. Here, a sadness of the soul causes the destruction of the body. The metaphor of lost faith and lost chastity casts itself over Tourvel's entire physical being, so that what she feels in her mind becomes manifest in her body. Just as Cécile decides to become a nun and wear a veil to repent for her adultery with Valmont, the Présidente must let her body die in order to expiate her misdeeds (Letter One Hundred and Forty- nine), "I was quite sure that I would die, and I had the courage to do so: what I cannot endure is that I should survive in misery and shame." ("Je me croyais bien sûr d'en mourir, et j'en avais le courage; mais de survivre à mon malheur et à ma honte, c'est ce qui m'est impossible.")
The Présidente de Tourvel's disease is, in itself, literary. Or rather, it is the transference of a literary technique, metaphor, into the space of the body. So involved is she by now in Valmont's sense of the world, that she cannot help dying by that same method he used to seduce her. Where he took the metaphors of her religion and made them apply to his love, she takes the metaphors of her religion and makes them apply to her body. As one might renounce a vice, so Tourvel literally renounces life.