Crossing Species Boundaries Is Even More Controversial than You Think

Jason Scott Robert and Françoise Baylis (2003) argue that scientific projects such as injecting human embryonic stem cells into an early mouse embryo raise hackles because they challenge a boundary criterion critical to the logical coherence of moral belief systems that privilege human beings. They might well be right, but the form of their argument presumes that such privileging is largely noncontroversial in bioethics. They write,

If we breach the clear (but fragile) moral demarcation line between human and nonhuman animals, the ramifications are considerable, not only in terms of sorting out our obligations to these new beings but also in terms of having to revisit some of our current patterns of behavior toward certain human and nonhuman animals. (emphasis in original)

Perhaps they intend this as an explanatory claim about the broad public reactions of disgust toward transspecies work involving human genetic materials, but I read them to be making the claim that there is a clear moral demarcation line between human beings and animals that is widely accepted among ethicists.

Clearly this is false, as is their earlier statement to the effect that there has been no ethical controversy over transspecies genetic manipulation of plants. In fact, Midgley (2000) argues that a similar feeling of revulsion over the use of genetically engineered food crops constitutes sufficient moral grounds for banning them altogether. A more recent article introduces the idea of "animal integrity" as an argument against genetic manipulation of animals, irrespective of whether human DNA is involved (Bovenkerk, Brom, and Van Den Bergh 2002). As someone who has spent the last decade working on the ethical controversies associated with agricultural genetic engineering (see Thompson 1997; Thompson 2003), I find it a bit depressing to see these issues so casually dismissed. Absent any discussion of genetic manipulation, a frontal assault on the moral demarcation line between human and nonhuman animals has been ongoing for at least 30 years. Singer's Animal Liberation (1975) is reputed to be the best-selling book by a philosopher in the twentieth century. In fact, there is no consensus among bioethicists regarding the demarcation between human and other species, animal or not. Only someone whose head has been deep in the sand of medical ethics would be tempted to make such a suggestion.

Robert and Baylis base their broad claim on the interesting and more sophisticated suggestion that simple membership in the human species forms the basis for human moral status, while factors such as the intent that lies behind a nonhuman animal's creation might enter into our view of its moral standing. I believe that this claim might have some merit were it properly qualified. First we must acknowledge that the problem of ascertaining the moral standing of human beings is itself quite amenable to different situations and that "membership in the human species" will not be a criterion appropriate for all of them. It might be immoral to deny certain human beings the right to vote, for example, yet we routinely deny children, convicted felons, and noncitizens this right and do not think that there is any injustice in doing so. This suggests to me that what Robert and Baylis have hit upon is a feeling that the circumstances under which a human being has come into being should not be thought of as a justification for putting persons (or their body parts) to certain instrumental uses, though it might be quite appropriate to see such circumstances as relevant to the disposal of nonhuman animals and their tissues.

Furthermore, it might be quite possible to ground this feeling in a nonanthropocentric conception of moral standing. Emerging views in animal ethics emphasize genetically-based and environmentally-evolved capacities, drives and functional needs as the basis on which any organism should be extended moral consideration. The complexities of human sentient experience and human capacities for socially- and symbolically-derived needs provide the basis...