Social teachings of Pope Pius XII  Social teachings of Pope Pius XII refers to encyclicals, apostolic constitutions and speeches by Pope Pius XII on non-theological issues involving medicine, science, education, social justice, family and sexuality, and occupations. Pius XII delivered numerous speeches to medical professionals and researchers. Pio XII, "Discorsi Ai Medici" compiles 700 pages of specific addresses. Pope Pius XII addressed doctors, nurses, midwives, to detail all aspects of rights and dignity of patients, medical responsibilities, moral implications of psychological illnesses and the uses of psycho pharmaca, but also issues of uses of medicine in terminally ill persons, medical lies in face of grave illness, and the rights of family members to make decisions against expert medical advice. Pope Pius XII went often new ways, thus he was the first to determine that the use of pain medicine in terminally ill patients is justified, even if this may shorten the life of the patient, as long as life shortening is not the objective itself. Other topics were the behaviour of medical doctors, facing pain and death, sterilisation, genetics, artificial insemination, painless child birth, the multiple moral aspects of developing medical technologies, morality in applied psychology, moral limits to medical research and treatment, and cancer treatment of children, and more. Pope Pius XII fully accepted the rhythm method as a moral form of family planning, although only in limited circumstances, within the context of family. Some Catholics interpreted the 1930 encyclical "Casti connubii" by Pope Pius XI to allow moral use of the rhythm method, and internal rulings of the Catholic Church in 1853 and 1880 stated that periodic abstinence was a moral way to avoid pregnancy. Some historians consider these two speeches by Pius XII to be the first explicit Church acceptance of the method. In his speech to mid-wives, Pope Pius XII offered this understanding of sexual pleasures: "The Creator himself... established that in the [generative] function, spouses should experience pleasure and enjoyment of body and spirit. Therefore, the spouses do nothing evil in seeking this pleasure and enjoyment. They accept what the Creator has intended for them. At the same time, spouses should know how to keep themselves within the limits of just moderation." To Pius XII, "The conscience is the innermost and most secret nucleus of man. There he withdraws with his intellectual capacities into complete separation, alone with himself or better, alone with God, whose voice echoes in his conscience.