I've been trying to resolve the whole abortion question for years, if not for everyone at least for myself. I am sure I won't be able to come up with a solution that will please everyone, but I felt I needed to come up with one that will satisfy me.
To be honest, I didn't start with some purely logical premise and work from there. I don't feel too bad about that, however, because most other people don't either. The difference is that most people simply make a decision and say "it's so." John Stuart Mill, in his brilliant treatise "On Liberty" (brilliant, of course, meaning "I agree with him") says that we tend to assume our opinions are "self-evident and self-justifying....People are accustomed to believe...that their feelings, on subjects of this nature, are better than reasons, and render reasons unnecessary." So I did what most people do: I went with my gut feeling. The difference is that I then turned and said I had to justify it. I don't have to answer the question for all time and all people, but I have to come up with something that makes sense to me, something reasonably logical and consistent with the rest of my principles.
Part of the reason I didn't start with some scientific premise is that there is no consensus in the scientific community on this subject. Some say life begins at conception, others hold that the fetus isn't "human" (another slippery and ill-defined term) until certain features appear, or until it's born.
In Norse mythology, there is a point where Loki, the trickster/anti-hero God has wagered His head in a bet against Thor, the thunder God. Thor isn't the brightest lightning-flash in the firmament, but He has managed to win the bet and Loki now faces the unpleasant prospect of having to pay up. He surrenders Himself to Thor, who grabs a handy axe with a look of "I've waited a long time for this moment, O Troublemaker" on His face.
As He prepares to remove the offending head, however, Loki pipes up and says "Now, mind you don't take any of the neck. That's still mine and I want to keep it." Thor is nonplussed for a moment, then has a bright idea and raises the axe again.
"But you have to take all the head," adds Loki. "I wouldn't want it said that I didn't pay my debt honestly and fully." Thor lowers the blade again. He is, frankly, more than a little pissed off. Somehow, He is unable to win against Loki, even when He has won and Loki is willing to pay His debt.
The Gods and Goddesses huddle around, trying to figure out how to handle this. Finally, they admit that there's no way to determine where the head ends and the neck begins, and Thor is forced to forgo His prize. He does, however, claim a bit of a consolation prize, and sews Loki's lips together. Loki goes off by Himself and tears out the thongs, but where his smile was formerly sly and mischievous, there is ever afterward a malicious curl to them.
This myth bears so well on the subject of abortion that I had to tell the whole thing. Just as no one was satisfied in the above myth, so no one will be satisfied by any "solution" to the question of abortion. Decide (whether legally or morally) that life begins at conception, and a huge percentage of the population will be up in arms, protesting loudly about women's right to control their own fertility. Put it at birth, and raise the question of abortions that are so late-term as to make the fetus distinguishable from a delivered baby only in terms of geography, as it were: is it inside or outside the woman? Where does it stop being "neck" and start being "head?"
Is there a way to find a "middle ground?" Admittedly, many people aren't looking for one, but I usually do. Physical development is not something that happens suddenly. Any criterion that was set as defining humanity would have a fuzzy zone around it where one might hear "Well, it's not really formed yet, so it's not really human" from one person and "Yup, that's a such-and-so. It's human, all right." Some would say the point of "humanity" is when the fetus can survive outside the mother. This one made a lot of sense to me, until a friend of mine got pregnant. She developed a condition which made it a race to see whether the baby would be born before the mother died. In an effort to save both, the doctors started piling on the hormones, trying to develop the baby's lungs enough that she could survive in an incubator.
Things worked out well. The mother survived and is back to her old self. The little girl is growing up nicely. Everyone's happy. However, this incident led me to re-evaluate my opinions on what qualifies as "viable." Do we say "if it can survive outside the womb at all, with the most sophisticated technology available, then it's a human being?" What if the most sophisticated technology isn't available? How do we know for sure? Do we require that hospitals try to deliver every fetus, every embryo, and then use heroic measures to save it? That doesn't seem practical.
Do we, on the other hand, remove the fetus or embryo, lay it on a table, and watch to see if it survives? How long do we watch? How about covering it up so it doesn't get too cold? Clearing an airway? Giving a little milk? Or an IV? An incubator? With this approach, we've just moved the damn' decision to after the fetus is removed, but the question remains: where do we draw the line? (incidentally, I have to say I'm totally opposed to both of these notions: I just put it in to make the point)
I guess we could go on as we have, with lawyers trying to decide medical questions, doctors trying to decide ethical questions, ethicist debating until everyone, is blue in the face (how do you get to be an ethicist, anyhow? Sounds like the least-boring job in the world), abortion clinics being bombed, pro-lifers screaming about murders, pro-choicers screaming about rights, and women making a difficult and painful decision every day.
I don't like that, either.
So, here's what I propose. And, like Thor's solution in the above story, no one's going to like it much.
In 1935, Erwin Schrödinger (1887-1961) formulated his wave theory of matter. Although it's dreadfully counterintuitive in many ways, it does seem to make sense at the quantum level. Basically, it says that the way we see the world isn't really accurate. We think of things being either solid or energy, but according to Schrödinger there are circumstances where matter actually can behave like enerby. The analogy works like this:
Put a cat in a box (howls of outrage from PETA). With the cat, put a small amount of a radioactive substance and a detector. The radioactive sample has a 50-50 chance of decaying in a set time. If it does, the detector will sense the decay and release a toxic gas, killing the cat (painlessly, of course).
According to quantum theory, the cat exists in a sort of limbo because there is exactly a fifty percent chance that it has died at the end of the set time. It's in a state called "quantum superposition," which means it's not really dead or alive until you open the box to look. It's the act of looking at the inside of the box that causes the probability to settle out one way or the other. Incidentally, this doesn't really work with cats or anything else remotely that large: it only works at the subatomic level. The analogy, however, is relevant.
Similarly, a developing fetus is to be considered a human being at the decision of the woman. If she says it's a baby, a human being, then in the eyes of the law it becomes a human being at that point. If she decides it's a human being, she can go to a doctor and get care for the child as a dependant under her medical insurance. If she's decided it's not a human being, then she can go to a doctor and have an abortion with no problems.
Like the story of Thor and Loki above, no one gets what they want under this system, and it's likely to stay ugly and angry, kind of like Loki. But on this matter, the issue is not a question of logic but of premises. In the abortion debate, it's not that everyone starts out with the same facts and then proceeds by logical steps to different conclusions: that's something that could eventually be resolved with more data. Here, it's a question of definitions, of a priori assumptions, and that's simply not something that can be logicked to a conclusion acceptable by all. It's kind of like mixing colors: if you mix pigments of the primary colors, you end up with black, but if you mix lights of the primary colors you end up with white. And that's about where the abortion debate stands right now: same verifiable facts coming to diametrically opposed conclusions because of different definitions.
Personally, I don't think there's a way to resolve this to everyone's satisfaction. Certainly the people on the opposite ends of the spectrum are simply not going to be satisfied with anything less than "my way," which means compromise is a forlorn hope. Rather than look for something that will be acceptable to everyone, I propose we go for something that will be equally unacceptable to the groups at either end of the spectrum and will be marginally acceptable to everyone in between.