I don't think Paul VI was speaking infallibly when he said that.
Unaccustomed as I am to engaging a Bapto-Buddhist on the topic of contraception....
The context is an address by Pope Paul VI to the College of Cardinals on June 23, 1964.Changing the teaching of Humanae VitaeThe below was written by Apotheoun, I think. Archives back to mid-April lost in the Great CAF Crash.
"I’m aware of the safeguarding of contraception on the basis of an intrinsic relation to the concept of “natural law”, but please explain this: Prior to the release of his encyclical Humanae Vitae, Pope Paul VI indirectly admitted in his address to the College of Cardinals on June 23, 1964 that the teaching on birth control may be changed - the Pope asserted the validity of the traditional RC teaching on birth control “at least as long as we do not feel obliged in conscience to alter it” (Osservatore Romano, June 24, 1964).
"The RCC places the sinfulness of contraception on a par with adultery, fornication, murder etc. as a mortal sin falling under natural law which cannot be altered. Is the Pope’s frank admission above indicative of a teaching which is unalterable by Rome’s criteria? What would your reaction be were a Pope to state that the teaching on adultery remains the same “as long as we do not feel obliged in conscience to alter it”??
I believe that we are seeing, on the Roman Catholic side, the beginnings of a re-formulation of this matter. Proabably by discerning more deeply the principle of double effect, contraception will find greater acceptance among the papal theologians, and the overly rigorous teaching of Humanae Vitae will be deepened and clarified.
To be frank, I am of the opinion that this will take place, not because of any imperative of the ecumenical dialogue with the Orthodox but because a failure to do so will see a deepening crisis of authority within the Roman Catholic Church itself. I do not think that the clergy and the laity will find themselves able to go on living with the strain of the present double speak and pretense which requires them to say one thing while actually doing another.
So, I am optimistic on this matter.
The original Italian of Paul VI's address...
È allo studio, diciamo, che speriamo presto concludere con la collaborazione di molti ed insigni studiosi. Ne daremo pertanto presto le conclusioni nella forma che sarà ritenuta più adeguata all’oggetto trattato e allo scopo da conseguire. Ma diciamo intanto francamente che non abbiamo finora motivo sufficiente per ritenere superate e perciò non obbliganti le norme date da Papa Pio XII a tale riguardo; esse devono perciò ritenersi valide, almeno finché non Ci sentiamo in coscienza obbligati a modificarle.
In tema di tanta gravità sembra bene che i Cattolici vogliano seguire un’unica legge, quale la Chiesa autorevolmente propone; e sembra pertanto opportuno raccomandare che nessuno per ora si arroghi di pronunciarsi in termini difformi dalla norma, vigente.