He never says the high birth rate is because of the Roman Catholic Church. Every place in Europe was deeply religious and had high birth rates at that time, regardless of the religion. He only blames secularization for the decline in birth rate. It just happens that the rapid secularization happened fastest where the Roman Catholic Church was strongest.
> I argue that the diminished sway of the Catholic Church, nearly 30 years before the French Revolution, was the key driver of the fertility decline
> ...the Catholic Church, threatened by the spread of the Protestant Reformation, took ‘be fruitful and multiply’ seriously and the purpose of marriage became explicitly multiplicative
> The decline of Catholicism, and fertility, in eighteenth-century France turned it from a demographic powerhouse – the China of Europe – to merely a first-rank European power among several
The first and third quotes only say that the birth rate diminished as Catholicism declined, which in a Roman Catholic area means secularization is occurring. Again, this is logically not the same thing as saying that Catholicism itself is the cause of the high birth rate. A birthrate can be high because of one thing and decrease because of something else.
The second quote still doesn’t show that the birth rate was high because of Catholicism. It doesn’t even say what the effect of that position was.
Could catholicism have been the cause of the high birth rate in France before it dropped? Sure. But the article never makes that claim. And it implies otherwise, because it mentions high birth rates around Europe including places that weren’t catholic.
