Is it fair to say that Paul VI wrote this encyclical with malice aforethought?
Gustave Martelet is said to have written Humanae vitae, or at least played a big part in it.
Of course, whether Gustave Martelet or Paul VI, the doc certainly buys into the overpopulation mythology:
2. The changes that have taken place are of considerable importance and varied in nature. In the first place there is the rapid increase in population which has made many fear that world population is going to grow faster than available resources, with the consequence that many families and developing countries would be faced with greater hardships. This can easily induce public authorities to be tempted to take even harsher measures to avert this danger. There is also the fact that not only working and housing conditions but the greater demands made both in the economic and educational field pose a living situation in which it is frequently difficult these days to provide properly for a large family.
and
23. And now We wish to speak to rulers of nations. To you most of all is committed the responsibility of safeguarding the common good. You can contribute so much to the preservation of morals. We beg of you, never allow the morals of your peoples to be undermined. The family is the primary unit in the state; do not tolerate any legislation which would introduce into the family those practices which are opposed to the natural law of God. For there are other ways by which a government can and should solve the population problem—that is to say by enacting laws which will assist families and by educating the people wisely so that the moral law and the freedom of the citizens are both safeguarded