I had the opportunity to discuss contraception (and other things Catholic) while having dinner with a Methodist pastor friend of mine. He is among the most conservative part of his denomination, btw.
Contraception came up and I pointed out that all christians opposed contraception before 1930’s - including his denomination.
I emphasized that those closest to the gospels in time (the fathers) taught against it. He countered that these same people taught against doing anything to limit the number of children - including abstaining.
I am aware that he is correct about that. I know that the number of quotes from the fathers opposing contraception would outweigh the number that could be found condemning abstaining, too… but there are enough quotes of the latter that he does have a point.
At that point I realized I had (at least temporarily) lost on this issue. I realized that my argument was based on the teachings of the fathers and that now my argument would have to depend on resorting to a subjective weighting of the number of teachings condeming contraception generally vs. the number condemning abstaining as well. How many quotes of the fathers teaching something does it take to make the point that the Church historically taught such-and-such? You get the idea.
BTW, I also know that the sheer number of quotes condemning contraception are very, very few vs. the number condemning other forms of mortal sin… this too makes it difficult to use the historicity angle in the argument.
Natural law won’t work at all with this guy but history might.
For myself, I only believe that contraception is wrong just because the Church today says so - period. The lack of historical support in the ancient church seems odd. The natural law argument seems weak because the Church does not condemn other things that seem to be violations of natural law such as fat and sugar substitutes which enable gluttonous people to continue eating more than they should and not suffer the consequences.