In this paper I will examine two responses to the argument from marginal cases; the argument from kinds and the similarity argument. I will argue that these arguments are insufficient to show that all humans have moral status but no animals do. This does not prove that animals have moral status but it does shift the burden of proof onto those who want to maintain that all humans are morally considerable, but no animals are.

This study is a contribution to the bioethical debate about new and possibly emerging reproductive technologies. Its point of departure is the intuition, which many people seem to share, that using such technologies to select non-disease traits – like sex and emotional stability - in yet unborn children is morally problematic, at least more so than using the technologies to avoid giving birth to children with severe genetic diseases, or attempting to shape the non-disease traits of already existing children by (...) environmental means, like education. The study employs philosophical analysis for the purpose of making this intuition intelligible and judging whether it is justified. Different ways in which the moral problems posed by reproductive technologies are often framed in bioethical debates are criticised as inadequate for this task. In particular, it is argued that the intuition cannot fully be made sense of in terms of harm to the children that such technologies help create. The study attempts to elaborate an alternative to that broadly consequentialist approach, by drawing on Martin Heidegger’s philosophy of technology, Hans Jonas’s ethics, and Aristotle’s practical philosophy, as it has been received and developed in the hermeneutical tradition. It is suggested that reproductive choices, unlike decisions for already born children, are characterised by a peculiar one-sidedness: the future child appears to the parents as something wholly theirs to decide about, not as a concrete other with whom they must interact in a responsive and attuned way. This is problematic because it means that such choices cannot call upon the particularised moral understanding only gained in interpersonal encounters. In particular, it makes them easily shaped by various tendencies, to which parents are always susceptible, to relate to children in instrumentalising ways, and at risk of reinforcing such tendencies. However, this does not mean that all uses of reproductive technologies are equally troubling. When selecting against severe disease the parents can rely on a widely shared illness experience to escape the dangers that one-sidedness involves. It is concluded that the intuition under discussion, thus explicated and in some ways qualified, makes sense morally. (shrink)