Well, if that’s how we measure death, then let’s use that to measure life. Both are present at 6-8 weeks, so no abortions after 6-8 weeks.
Actually, that is a little bit of a risky argument. We have the measurable beginnings of brain development at that point, but if you want to use the same basic clinical definition for both ends of life, you are possibly looking at the 25th or 26th week.
That is the point in which synapses, actual pathways in the brain, start to develop quite suddenly and we see things like stimulus related heartrate accelerations. Before this point, we don’t really have cranial reflexive responses, the typical definition of “brain dead”.
One thing that I find useful in having these sorts of conversations with secularists is being clear about what, exactly, Catholics believe. We do not believe, as a matter of faith, that a fertilized zygote is unquestionably a human person with a human soul. Nor do we hold that human life, on life support, in the absense of detectable cranial responses, is still an ensouled human person. On those questions, the Church freely admits that we do not know.
What we do believe is that each human person has a soul which is a unique creation of a God who can, and does, love us each infinitely. Since we are called to love others as the Lord loved us (or at least as much as we love ourselves - perhaps as close as we can come), we treasure life in all stages and in all forms (wealth or poverty, sinfulness or rightousness, healthy or ill). Since we don’t know the exact moment we are infused with the soul or precisely when it departs us, we error on the side of life.
When we focus simply on the question of abortion, it can be hard for secularists to see our point of view. No abortions to save the life of the mother is something that even most Catholics have a hard time following in practice. But it is consistant with our view of infinite value at any stage and any state. It also explains the question of rape and incest. We are called, as Christians, not to judge each other, let alone judge unfairly. The fetus did not commit the crime.
But like saving the mother’s life, the emotional response to rape and incest is understandably strong. So I usually point out that the true test of a belief is rather you will hold it when it costs you something. We Catholics don’t just waggle our fingers at women and say ‘no’ to abortion. We hold life in ultimate regard in all cases. Evangelium Vitae ties abortion, euthanasia, and even the death penalty all together as examples of the same teaching, the inalienable rights of the human person.
