The Angelus, March 1994, "The New Catechism: Is it Catholic?": "We are far from the luminous teaching of Pius XII concerning the 'grave motives' which can justify a (natural) regulation of births."
Mike, this is true is it not? Other than your "slippery slope" argument, isn't it just a fact.
Actually SJB, it's not. Since Antipope Pius XII not only never defined "grave motives," but even painted a very broad and vague picture of what those "may be" and "are" he left the floodgate open for such as we see nowadays, namely that all sorts of things are being called grave motives, where truly there is no such thing as a sufficiently grave motive that would allow couples to continuously engage in their lusts for one another while attempting to prevent conception. That is birth control, plain and simple.
If the reason is sufficiently grave to want to avoid bringing children into the world at all, then
any use of the marital act at all would risk aggravating that "grave reason" if conception should occur. As such, the act itself is to be entirely avoided.
And by the way, I don't know why this has not been mentioned yet: It takes time before the woman necessarily knows she is pregnant - the child doesn't just plop out a day or two after conception.
In other words, an unexpectedly pregnant couple (God forbid!) has TIME IN WHICH TO WORK to ensure that the child receives the Christian upbringing and temporal amenities it needs long before it even comes in to the world.
No couple that works and prays in Faith and submission to God's will is going to be left out in the cold.