"We often hear that the church accepts natural methods of birth control while she rejects artificial means. This is not true. The Church accepts periodic sexual abstinence, based on the virtue of chastity, but she condemns every form of contraception. Contraception is "an act which has as its goal the prevention of propagation" (Humane Vitae, No. 14). This is not the case with periodic abstinence. With periodic abstinence, the person is honoured in the sexual relationship-the wife through her own biological rhythm, the husband through the sperm that he gives. No separation disturbs the oneness of the marriage act, the oneness of spirit and body. There is no contradiction between the (good) goal and the means. The Church considers contraception a moral disorder, not for biological, ecological or naturalistic reasons, nor out of fear for science and technique, but for spiritual, anthropological and metaphysical reasons. Contraception casts man himself in the role as lord of life, allowing him to use his body as a piece of material that is subject to his desire; as an object he can manipulate as he wishes. His desire then becomes the only criteria of his actions. His morality is based on situation ethics; on subjective standards. By periodic abstinence, however, man accepts himself as a creature of God, sublimating his will to that of his Creator. He sees his body as a sign of his dependence, and at the same time as a symbol of his transcendence. His desire - which is always obscure and confused - submits itself in freedom to the law that is written in his nature, and which therefore becomes a reasonable, true human desire."