marriage includes both rights and obligations. Abstinence within marriage is also highlighted in his teachings. Pius took issue with the argument that abstinence is an impossibly heroic act. Citing Augustine, he argued that if natural union is not possible, abstinence is required. And, he added, in the time of World War II, so many acts of real heroism were required of men and women in so many countries, against which sexual abstinence paled in comparison. The human body and its needs should not be the centre of gratification but need to be sublimated to spiritual priorities that reflect the divine design and destiny. Marriage is not the highest value and human dignity must be preserved and applied in the marital act. The teachings of the Church reject a hedonistic view of the human body, while recognizing and valuing its divine origin and dignity. The Church thus protects the dignity of men against an over-emphasis on sensuality. Body and soul Early Church writers, while defining the position of the body within theology, had focused a great deal of attention on the creation of body and soul. "The body of man was created by God" (de fide) according to the teachings of two ecumenical councils Lateran IV and Vatican I. Pope Pius XII taught that the question of the origin of man's body from pre-existing and living matter is a legitimate matter of inquiry for natural science. Catholics are free to form their own opinions, but they should do so cautiously; they should not confuse fact with conjecture, and they should respect the Church's right to define matters touching on Revelation. For these reasons, the Teaching Authority of the Church does not forbid that, in conformity with the present state of human sciences and sacred theology, research and discussions, on the part of men experienced in both fields, take place with regard to the doctrine of evolution, in as far as it inquires into the origin of the human body as coming from pre-existent and living matter - for the Catholic faith obliges us to hold that souls are immediately created by God. In an October 22, 1996, address to the Pontifical Academy of Sciences, Pope John Paul II repeated the position of Pius XII adding: In his encyclical Humani generis (1950), my predecessor Pius XII has already affirmed that there is no conflict between evolution and the doctrine of the faith