which was pretty clearly stated and never rebutted, rescinded, or otherwise revoked to my knowledge.
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Faithfulness to God's Design13. Men rightly observe that a conjugal act imposed on one's partner without regard to his or her condition or personal and reasonable wishes in the matter, is no true act of love, and therefore offends the moral order in its particular application to the intimate relationship of husband and wife. If they further reflect, they must also recognize that an act of mutual love which impairs the capacity to transmit life which God the Creator, through specific laws, has built into it, frustrates His design which constitutes the norm of marriage, and contradicts the will of the Author of life. Hence to use this divine gift while depriving it, even if only partially, of its meaning and purpose, is equally repugnant to the nature of man and of woman, and is consequently in opposition to the plan of God and His holy will. But to experience the gift of married love while respecting the laws of conception is to acknowledge that one is not the master of the sources of life but rather the minister of the design established by the Creator. Just as man does not have unlimited dominion over his body in general, so also, and with more particular reason, he has no such dominion over his specifically sexual faculties, for these are concerned by their very nature with the generation of life, of which God is the source. "Human life is sacred—all men must recognize that fact," Our predecessor Pope John XXIII recalled. "From its very inception it reveals the creating hand of God." (13)
Unlawful Birth Control Methods14. Therefore We base Our words on the first principles of a human and Christian doctrine of marriage when We are obliged once more to declare that the direct interruption of the generative process already begun and, above all, all direct abortion, even for therapeutic reasons, are to be absolutely excluded as lawful means of regulating the number of children. (14) Equally to be condemned, as the magisterium of the Church has affirmed on many occasions, is direct sterilization, whether of the man or of the woman, whether permanent or temporary. (15)
Similarly excluded is any action which either before, at the moment of, or after sexual intercourse, is specifically intended to prevent procreation—whether as an end or as a means. (16)
Neither is it valid to argue, as a justification for sexual intercourse which is deliberately contraceptive, that a lesser evil is to be preferred to a greater one, or that such intercourse would merge with procreative acts of past and future to form a single entity, and so be qualified by exactly the same moral goodness as these. Though it is true that sometimes it is lawful to tolerate a lesser moral evil in order to avoid a greater evil or in order to promote a greater good," it is never lawful, even for the gravest reasons, to do evil that good may come of it (18)—in other words, to intend directly something which of its very nature contradicts the moral order, and which must therefore be judged unworthy of man, even though the intention is to protect or promote the welfare of an individual, of a family or of society in general. Consequently, it is a serious error to think that a whole married life of otherwise normal relations can justify sexual intercourse which is deliberately contraceptive and so intrinsically wrong.
Lawful Therapeutic Means15. On the other hand, the Church does not consider at all illicit the use of those therapeutic means necessary to cure bodily diseases, even if a foreseeable impediment to procreation should result there from—provided such impediment is not directly intended for any motive whatsoever. (19)
Recourse to Infertile Periods16. Now as We noted earlier (no. 3), some people today raise the objection against this particular doctrine of the Church concerning the moral laws governing marriage, that human intelligence has both the right and responsibility to control those forces of irrational nature which come within its ambit and to direct them toward ends beneficial to man. Others ask on the same point whether it is not reasonable in so many cases to use artificial birth control if by so doing the harmony and peace of a family are better served and more suitable conditions are provided for the education of children already born. To this question We must give a clear reply. The Church is the first to praise and commend the application of human intelligence to an activity in which a rational creature such as man is so closely associated with his Creator. But she affirms that this must be done within the limits of the order of reality established by God.
If therefore there are well-grounded reasons for spacing births, arising from the physical or psychological condition of husband or wife, or from external circumstances, the Church teaches that married people may then take advantage of the natural cycles immanent in the reproductive system and engage in marital intercourse only during those times that are infertile, thus controlling birth in a way which does not in the least offend the moral principles which We have just explained. (20)
http://www.vatican.va/holy_father/paul_vi/encyclicals/documents/hf_p-vi_enc_25071968_humanae-vitae_en.htmlBasically, ya got your rhythm method and that's it. :shrug: