My consistent argument for allowing pre-20 week abortion is the mother wants it or if circumstances demand is as follows:-
1) Only presently existing beings (not future beings) have intrinsic right to life in the moral sphere.
2) Beings exist only when their physical stratum has the capability to host (or generate) complex consciousness with inner mental states (the mind, the self, etc.). This is a minimum criteria. It is the mind that defines a being as a being. (Justification here LINK).
3) The physical substratum of pre 20 week fetus has no such capability according to currently understood science. See Evidence here LINK. Original Article here LINK
4) Thus a pre-20 week fetus do not have an intrinsic right to life.
5) Given (4) mother's bodily autonomy and choices take precedence over the fetus prior to 20-21 weeks. Whatever right the fetus has (or does not have) comes from her mother (extrinsic or derived rights).
6) So if a mother chooses to, she can abort the fetus without any moral objections. Or she can carry it to term.
7) Post 20 week things get more complicated. And you will need justification of clear danger to the mother's life to justify abortion.
I would like to hear the arguments against these points.
People that find abortion repugnant do so at a visceral level. They aren't interested in arguments about freedom, autonomy, or neural maturity. They won't even read that further once they realize what it is.
I am pro-choice. My argument doesn't look like yours, but it assumes like you do that there is a time in a pregnancy when abortion is a moral option. For me, the procedure becomes immoral if the fetus is mature enough to experience terror and lethal pain. Before that, the question for me is, who will make the decision whether an early term pregnancy comes to term, the pregnant woman, or the church using the power of the state?
Notice that there is no reference to whether the fetus is called a person, human, a human being, a child, or alive. Arguments based in definitions don't change the moral calculus. The moral status of the act doesn't change for me n matter how those questions are answered.
Intrinsic rights are those rights that are conferred due to some property that is internal to the entity under consideration.
I agree with others about inherent rights. There are no rights except those enumerated and enforced by human beings. This is apparent when others speak of God-given rights. If we had waited for God instead of crafting a Bill of Rights, we'd still be waiting.
Moral truths exist regardless of whether they are acknowledged/codified or not (just like any other truths). Here moral truths are basically the set of true statements that are answers to the question: what is the optimal sets of allowed and disallowed behaviors that a set of interacting experiencing beings (of some description) can (or cannot) engage in order to maximize physico-mental well being and minimize suffering. There are true statements that you can make in order to answer this question. And they would be in the realm of moral truths.
That happens to be my position as well - utilitarianism for crafting societies (and the Golden Rule for personal interactions) - but I can't call that anything more than a subjective judgment. I can't tell you why I value those things or care about others, just that I do. Sure, they promote human well-being, and that is a worthy goal in my estimation, and that approach has practical value to those who root for humanity, but it is just an inescapable intuition, not something that I can call a truth as I use that word. It's an is-ought problem. Truth is on the is side, moral values on the ought side. I can't connect them. I can't call any should statement truth.