Let’s put it this way.
Pro-aborts use anything they can to discredit the pro-life position. If you claim to be pro-life based on some non-scientific criterion, then you give the pro-aborts the ammo they need to ridicule and dismiss the pro-life position. They don’t just laugh at the idea that “ha-ha-ha, he actually believes that a just fertilized egg is exactly like a newborn baby”—they extend that out to ridicule any claim that a baby can possibly be alive before birth.
IMO, the strongest position you can have is one that is based purely on objective, observable, measurable characteristics of the embryo.
Scientifically, there is nothing particularly special about a fertilized egg. It is made when two living cells fuse together to become one living cell. Since cell fusion is a common event, fertilization is not a defining event. Neither is unique DNA. Even though cells are dividing in the fertilized ovum, they have no form. Form and function don’t start showing up until after implantation. You don’t need a scientist (like me) to tell you that everything you know, all of your perceptions, feelings, thoughts, etc., are only possible because you have a brain in your head, and that removal of the brain—even if the rest of your body can be kept alive—would essentially eliminate you as a person. So, as a measure of what makes us human, I think that formation of the nervous system is the defining event. Before the nervous system develops, there is nothing but a clump of featureless cells. After the nervous system starts to develop, there is an embryo that has awareness of its world.
Also, I don’t believe that God implants a soul at fertilization. I know it is a romantic concept for some people, but I am also aware that most fertilized ova never even implant, much less go on to become embryos. I do not believe that God kills off 9 souls for every one that is allowed to live.
I don’t care if I get ridiculed about this. Why should I?
Nor do I spend time arguing about when the soul enters the person. The soul does enter the body at a particular point. That’s a fact, whether we believe it or not.
Just like the fact that if I drive my car into a wall it’s going to get smashed whether I believe it will or not.
I’m not sure to what you are referring, but I can assure you it was a defense I was making, and certainly not an attempt to change anyone’s mind.
There is no science yet, nor is there any forseeable, of when the soul takes its place.
When I assume that it happens, as I do, at the time a person is formed, at fertilization, when DNA is that of a different person, then there is order.
Is there some scientific data to which you can point that causes you to assume that I should believe your assumption that God doesn’t take on should that don’t make it to implantation?
Please don’t lecture me on what God wants, nor on your assumptions on when a person becomes a person. I prefer to ignore those uninformed ideas of people around me who want to tell God how things are.
There are many theologically informed philosophers and Biblical researchers of good will whom I prefer to hear. They never veer away from the assumption that God invented sex, not us, and we are best served by using it according to His will - within a marriage of good intent.
It’s simple. And it is impervious to ridicule, because it doesn’t care about that.