[boredhedgehog]

> Until the mid-late 1800s, abortions were legal, and even allowed by the Catholic Church until "quickening" (when you were able to feel the fetus kicking/moving).

No, the Church has never allowed abortion. When gradual ensoulment of the fetus was the dominant scientific theory, the quickening marked the difference between homicide and murder.

[defrost]

Medieval intellectuals, including Augustine, Thomas Aquinas, Hildegard von Bingen, believed that the fetus only received its soul around 40 days after conception.

No soul, no murder.

[Xunjin]

Do you have a reference? Not doubting you, just want to learn more about it.

[defrost]

Forty plus years ago I took Philosophy mainly for twentieth century logic under Graham Priest and alongside a few peers that now do fancy Royal Institution physics, run their own philosophy departments, etc.

As part of that I was roped into also taking Morals and Ethics led by a talented Jesuit type whose name escapes me and who went at depth into many such questions; I had the actual original texts by the three I mentioned in front of me back in the day.

Right now, the best I can do on the fly is point at, say:

https://plato.stanford.edu/entries/augustine/#SoulCreaBein

and state that Augustine made a strong case for soul–body dualism and considered at least three paths for the soul to join the body, along with the belief that that a soul must also leave a body, and (IIRC) wrote about "the quickening" (motion of a fetus) being a sign of a soul either transfering in part from the mother or arriving "from outside" via God, etc.

He also remained uncommitted to "one true notion" for the bulk of his life (according to the Stanford and other articles I skimmed).

Augustine is, I believe, the best known for writing on soul-body dualism but I have not taken a deep interest in this area of Philosophy and am by no means an expert.

If you're interested in leaning more about the thoughts that humans have had on the matter that's likely a good starting point for reading material and references, going forward it'd be best to find a diverse group of other interested parties in that part of Philosophy, there will be no absolute answers, just a wealth of conjecture and reasoned arguments for sometimes opposing opinions.