That is a philosophical question, not a scientific one... If it were scientific, it would have been resolved already. Many people seem to make an implicit distinction between “human life,” and “personhood.” Then, many people seem to judge killing a “human life” as less wrong than killing a “human life” that is also a “person.”
An embryo, e.g., is clearly a human life. It is less clear whether an embryo qualifies as a person. I believe this is the root of the disagreement.
Arguments about viability, the potential of the fetus, etc. are all philosophical nonsense IMO. The question would be decided easily if we could just:
1) resolve what characteristics a life must have to qualify as a person, and
2) resolve at what point a fetus attains those characteristics.
I won’t hold my breath.
The child exists at conception:
“Begat sons and daughters” Gen 5:3,4,28-30 Begat always refers to conception and fertilization.
“children & sons in womb” Gen 25:21-22; 2 Ki 19:3; Ruth 1:11
“a man child conceived” Job 3:3 notice the difference: day of birth, night conceived see Rev 12:5 “man child born”
“mother” of unborn child Num 12:12; Lk 1:43
Rom 9:11 for though the twins were not yet born, and had not done anything good or bad
“baby leapt for joy” in mother’s womb Lk 1:41,44
conceived a “son” Lk 1:36; Acts 7:29
“Whosoever is holy [i.e., in a state of sanctifying grace], let him approach. Whosoever is not, let him repent” (Didache 10)
You are wrong.
Imagine a man. Let's make him about 40, with salt and pepper hair and wire-rimmed specs.
Let's give him a job...he runs a bookstore. His wife and son help him. He has a formal manner that his customers like and he wears a suit to work.
Now, you have no doubt in your mind that this man is both a human being and a person, right? Keep that in mind.
Let's give the bookseller an accessory for his suit: A yellow, six-sided star sewn onto the left lapel.
You see, only an idiot would doubt his personhood...but they still put him, and six million people like him, on the cattle cars headed for Auschwitz and Treblinka. And we could play this mental game with genocides from all over the planet...Rwanda, China, Ukraine, Armenia, Cambodia...
Our law calls the child in the womb a non-person so we can kill them. Any philosophical debate on the matter springs from the same well.