The recent discovery of Dr. Kermitt Gosnell's malpractice has been fanning flames in the abortion debate. I think one of the biggest problems in this debate - is a lack of nuance. This is really tricky ethical/moral stuff. There is a lot on the line for people, and the issue is in many ways a sort of Rorschach test.
For instance, I don't believe there is a God or creator, or that any of us has any soul, or "meaning" in the grandest sense. I believe we are simply a highly evolved set of molecules placed in a specific sequence, that the original "life" was able to assemble a series of amino acids and self-replicate trillions of times over, covering the Earth with all manner of life we now see around us. In this way my ear cells, when placed in a petri dish are just as "alive" as anything or anyone. Yet I not only believe but know that life has meaning in a smaller sense - actually quite literally as a manifestation of my ability to sense and "make sense" of the world. Thus, I feel emotion and am able to empathize with fellow creatures.
Yet any meaning I assign to life is well, not arbitrary, but relative to my world view, my culture, my reasoning, etc. This is how I believe, for instance, that it is wrong to cause animals to suffer. But I realize that this is a meaning that I have created in my mind, at least in so far as it is something I have thought about and come to a conclusion on. Yet I realize that others may have different, yet reasonable views. I think they are wrong, but they won't think so, because their meaning is different than mine. And their views are likely entirely consistent with their worldview. They don't view animals the same way as I do, and so don't empathize the way that I do.
When Rick Santorum brought his dead child's fetal body home to sleep with, he had given it a much different meaning than I would have. When my wife had a miscarriage, I couldn't have cared less. The baby didn't feel pain, we didn't know it, and I had no reason to empathize with it - no more than I would my sperm or my wife's unfertilized eggs. There's nothing especially significant to me about the fertilization process. At a certain point, a the baby begins to feel, or at least develop the capacity to suffer. Although even then, suffering doesn't come into it so much - I no doubt suffered considerably when I was circumsized.
In any event, there must come a point at which infanticide is wrong, either within or without the uterus. We certainly can't have people killing their children. So how does one find that line? The sort of strict, black & white approach would be to draw a line in the sand at a definition of "life". But isn't that a sort of tautological, semantic device? As I mentioned previously, biologically, I don't believe anyone is really a "life" any more than any cell anywhere is. This is where we each simply create meaning. For me, "life", or human life at least, is experiential - in the sense that it is something that emerges from the uterus, and immediately takes on special significance to the immediate relations, and to a lesser extent larger society. The baby has feelings and needs, and the community has an interest in giving it great significance.
Do I have a perfect line I can draw that says after this moment the baby takes on enough meaning for its life to be spared? Certainly not. "Meaning" is almost unquantifiable by definition. When do cookies become "good"? When is a song "beautiful"? Yet we obviously have to make rules as a society, even if they must in a sense be very arbitrary. Rules often are. What should the sentence for theft be? How do you quantify the wrong that was done? It seems that if any debate demands nuance, it is abortion. Yet as is often the case in controversies where one's worldview is at stake, rigidity seems so much the more powerful and "righteous" - one might even say easy, stance.
Some will think me a murderer. Some will say my nuance leaves the door open for a slippery slide into the evils of moral relativism. I see no reason for that to be the case. Just because I know a 70 mph speed limit is somewhat arbitrary, I know that speeding is dangerous. So too do I know that killing people is wrong. I just don't know exactly when one becomes that sort of "human". In standing up for nuance, and rejecting the safe, firm chains of rigidity, one goes out on a limb. Yet there is a great faith there. It is a faith in the reasonableness of humanity. Sure we can be brutal and inhumane. But we can also be incredibly wise and reflective. The irony of nuance may be that the greatest evils have come not from nuance, but rigidity itself. Because with rigidity comes a closing of the mind. That may be a good thing if the cause is good. But what if the cause is bad? And once rigidity has set in, how would one know?