Abortion: Life versus Ensoulment

The public's opinion regarding abortion has been fairly stable over time.  This leads to argumentation being aimed at two distinct groups.  First, is the young who are forming their opinions on the subject, and second, those who have a divided opinion (legal only under certain circumstances.)  This latter group constitutes a majority of the population, but also tends to move in the opposite direction of the abortion legal at all times group (ie, the only certain circumstances group moves in and out of the at all times group.)

This leaves the right to life movement in a bind.  The arguments being put forth are keeping the "base" happy, and helping to keep public opinion relatively static, but are not winning the hearts and minds of the persuadable population.

Simply arguing that the baby is "life" and therefore shouldn't be aborted is a facially flawed argument.  Anyone who has had a bacterial infection knows that a single cell constitutes life.  It's good to kill bacteria if it is causing an infection.  Even a variation of the argument that life has value and shouldn't be killed is likewise easily batted away.  We can kill a pig for bacon with no moral reservation (assuming the slaughter method is humane.) 

This leaves the argument that we shouldn't allow abortion because it is "human life."  This is true, and from the moment of conception the baby is human.  That's also self evident in that nothing is added or taken away from the fertilized ova, so it may be rudimentary and not viable, but it's still human.

What then can be argued that would start to persuade the persuadable under certain circumstances crowd?  Presumably, the under certain circumstances crowd is so aligned because of two main reasons.  Either they believe abortion should be allowed until viability (or some other defined point) or they want exceptions for rape/incest/life of the mother.

Since the humanness of the baby isn't enough of an argument to persuade on abortion beyond levels already present a focus on the warrant is the next most logical place to adapt argumentation.  Often times the argumentation on the humanness of the baby fails to persuade because the warrant isn't defined.  Solution: define the warrant.  For this I would suggest ensoulment as the underlying warrant as to why the humanness of the baby is what should prevent abortion. 

Although the moment of ensoulmet has never been established - and likely cannot be established as science is incapable of testing for a soul in the womb - the metaphysical writings generally accept ensoulment at a very early stage of development and since the publication of Paulo Zacchia's Quaestiones Medico-Legales, question 9.1 ensoulment upon fertilization is the prevailing viewpoint.  After all, something that can be added can be taken away and the soul is not viewed as separable form the body so long as the body lives.      

While arguing ensoulment will not persuade the baseline quarter of the population that believes in abortion under any circumstance, they are not the target audience.  The majority who believes in limited abortion is the audience since they already at least partially accept limitation of abortion.