Margaret Somerville was on Alan Gregg's television programme last night.
She claimed that there are two camps among ethicists:
1)The principled group (including herself) and
2) utilitarians, ie. those who are seeking the greatest happiness for the greatest number of people.
In proclaiming herself to be "principled", she mainly meant that she believes that fetuses and their predecessor blastomeres have value as potential humans. Thus, she argued that it is "principled" to oppose stem cell research because stem cells partake of humanness in some way.
A deep problem with her thinking is that she takes the world as a given.
So, for example, she thinks she is being principled because she makes no cost-benefit calculation made with respect to the fetus.
But when it comes to the life of the person doomed to death from cancer, she is indifferent. Somehow, THAT life isn't sacred. She makes her one-sided calculation, and leaves it at that.
But in the real world, her decision AUTOMATICALLY and INEVITABLY causes the death of the cancer patient. Claiming that you won't do cost-benefit is just a way of saying "screw off" to the person with the disease.