The opposing sides of the abortion debate rely on arguments something like the following
Anti-Abortion: A human fetus is a human. Abortion kills that human. Killing is wrong. Hence abortion is wrong.
Pro-choice: No-one has the right to tell someone else what to do with their body. It is a pregnant woman's choice.
First we should clarify that we are discussing human abortion here, and not that of so called 'lower' animals. Weird religious arguments aside, most people agree that a human life is more important that the life of an animal. But at what stage does a cluster of matter become a human being? Given that animal life and human life are not distinguishable (except through DNA testing) at the early stages of life. When does human life become more valuable, and for that matter when does life actually begin?
Does it begin at contraception (the banning of condoms by the Catholic church suggests they believe this) at conception, at the first cell splitting, at the point where the heart starts beating, at the point where the child is capable of survival outside the womb, or at the chosen time of birth?
Apparently, the value judgement that a human foetus is more important than that of an animal is some kind of recognition of potential.
Interestingly, the pro-choice movement generally doesn't even try to address this argument - insisting instead that the rights of the mother are paramount over any egg, zygote, embryo or fetus.
And here we see the subtle incoherencies of the mainstream pro-choice movement. In this case, they argue for individual human rights - the woman is an individual separate from her offspring (or potential offspring), and she has sovereignty over her body, and hence has the right to remove foreign bodies from it.
But in most other rights issues, it is the pro-choice activists who undermine individual sovereignty and initiate force. The leftist mindset believes in violating individual sovereignty for the good of others. They advocate forcing people to help those around them. The feminist movement, so popular in the 1980s and 1990s pushed very hard for single mothers to be given both government assistance (ie taxes taken by force)and child welfare money from the fathers of those children.
The feminist view seems to be that women have individual sovereignty over their own bodies (ie they have no obligation to carry a fetus even for its survival), but also sovereignty over the bodies (and the property) of others. The taxpayer has an obligation to pay for the raising of her children (if she chose to have them). The father of the child has an obligation to pay for it even if he is not permitted to carry out the usual roles of a father.
This position is typical of the incoherence of the left.
The position is also typical of the attitude of the Conservatives. The Conservative doesn't believe in individual sovereignty (except when arguing for lower property taxes). The conservative believes in violating people's bodies 'for the good of society', and (just like the hard-core socialist), believes that society hast he right to dictate the use of your resources, your possessions, or your body towards that goal.
So which side is morally correct in this case?
A thought experiment may guide an answer:
Note that the question is not whether saving the person is a good thing to do. Most people agree that saving the person is a good thing. The issue is whether you have the right to remove yourself and let the person die.
Some would say that no-one has obligation to another. Others say you have an obligation to carry the machine and let the person die.
If your answer is that you have an obligation to save the person, then you do not believe in personal sovereignty. Surely it is also your responsibility to give money to the unemployed, to the sick.
If your answer is that you have the right to let the person die, then surely you have no obligation to pay taxes for someone else's welfare.
See