I might seem a bit incompetent because I've not the knowledge on many of the background information that might be required for such a debate, but I'm going to try and throw some things out there.
If a parasite is not considered a living organism, then this is not valid, but do parasites not require a proxy source to support their own life processes? In one of the most degrading perspectives, a fetus can be viewed as a parasite that must rely on the mother to develop and function properly. If parasites are alive, aren't fetuses too?
And what I don't get is the whole reliance on what the court views as an individual. Obviously, there had to have been an original basis that had to be concluded upon that prior to the conclusion of that perspective, the basis was simply an opinion, much like what is trying to be proposed as the "other" definitions of when life begins/what being alive is.
Another thing I don't get: Why the hell would a murderer be convicted on two accounts of murder if he were to kill a pregnant women (not to say that I am defending such actions)? If the court concludes that the woman counts as one murder and the unborn fetus counts as another murder, would that not mean that the court considers the fetus to be "alive" at the point and time at which they were killed? Why is this not applicable to abortion? Is it killing or is it not? Why is it that the definition varies selectively? Of course, this can be invalidated if the fetus that counts as a murder qualifies for the definition of what "alive" is.
Personally, I believe that abortion comes down to the ability of a woman to choose and the consequences of those choices. I am a Roman Catholic, but I try to avoid the infusion of any of my religious beliefs into my discussions on moral issues. To be blunt, I believe that this "right" provides ample opportunity for these people to become a whole lot stupider. They whine, complain, picket (which either side does, mind you, whoever talked about pro-life groups going around protesting and shooting doctors, so that assertion is undoubtedly invalid) about the right of a woman to choose, but did they not have the right to choose to engage in sexual relations? They ignore the inherant responsibilities that are coupled with any action and seek to avoid the consequences of such actions. To me, abortion is an escape that serves to train people in the ability to avoid mistakes that should educate by experience. It deprives them of experience, of a sort of education that can only be found in that experience. It serves to weaken them.
EDIT: I love debate. Unfortunately, I will gone this weekend, so I probably won't be able to see how this turns out...Aldo, I must say, I admire your tactics and your etiquette regarding discussion. You are very respectful and respectable.