The clearer cases are the cases where you have a condition in which it is likely to be distressing or painful for the child and perhaps for the parents as well, and you don't have another family who would be willing to adopt the child because of the severity of the disability. Then what you have is the preferences over the lifetime of the child, which may be difficult to work out. However, maybe at least in some conditions the life is so poor and in so far as the child has preferences they would be negative ones against that kind of existence — plus the preferences of the parents of the child who would be caring for the child throughout its life.

Against that you may have the attitudes of others, and if you are talking about the attitudes of the community as a whole, it's just one thing going on that they don't like. For most people, if you ask them whether they accept infanticide then they might say no, but is that a major preference for them that, if infanticide were to be practised in hospitals, would disturb their entire life? I would say no. The evidence of that is that infants with disabilities are allowed to die. Some people are opposed to that but it does happen and it doesn't really greatly disturb the  lives of those who are opposed to euthanasia. So I think it's not necessarily going to outweigh the preferences of the parents,  who are much more centrally concerned in this situation.

DJ: You would extend this obviously to other cases, at the end of life —euthanasia.

PS: The difference between the infanticide cases and euthanasia is that at the end of life you either have or have had a being who is capable of making decisions about his or her life. That's important. The easiest case for me is the case in which the person says, "I have got a disease that is terminal, I know I could perhaps live another month, another three months, but I feel the quality of life that I have now makes it no longer worth living — so I want to die."

That's that person's preference. That then, to me, becomes the central factor. Some other preferences might be relevant, but that is the central factor.

Suppose on the other hand you have someone who is no longer conscious, or maybe has Alzheimer's disease, or is no longer capable of thinking about that issue, but did have preferences before, then I think that we should take account of those past preferences. So if the person was a fully paid-up member of the Voluntary Euthanasia Society [now called Dignity in Dying] and said, "If this ever happens to me, then I don't want to go on living," then I think we have a situation rather like that of the competent person. On the other hand, if the person said, "No matter what, I want to live as long as I can," then we should respect that preference too, at least within the resources which we have available to do that.